The following  was written to address the most common questions I receive from readers and personal training and phone clients.

Calories Versus Macronutrients

Whether you’re trying to lose fat, gain muscle, or maintain your current weight and body composition both are important.

Calorie intake is important for a change in fat or lean mass, if you don’t have a deficit you’re not going to lose much fat, if you don’t have a surplus you’re not likely to gain much muscle. Macronutrient ratios are important because they influence what you lose or gain.

Keep in mind, the goal isn’t indiscriminate weight loss or gain, but improved body composition. You want less fat, more muscle, or both, not just a change in weight.

Also, overall health should be a high priority and both the amount and what you eat influence this. If you eat the appropriate amount of calories but most of it is polluted, nutrient-deficient crap you’re going to look and feel bad. If you eat nothing but healthy, whole foods, but you regularly eat too much or too little, you will be healthier but you will still be underweight or overweight.

Eat the appropriate amount of the appropriate types of foods for your body and your goals.

Calorie Intake

For most people who have a healthy body composition or are within a few pounds of it, just eating the appropriate types of foods will result in your appetite being a reliable indicator of need. As long as you eat until you’re not hungry, rather than until you’re full, you don’t need to worry too much about tracking calorie intake.

For those trying to achieve very low levels of bodyfat without sacrificing muscle, or trying to build as much muscle as possible with minimal fat gain, keeping track of everything becomes more important. If you fall in this category, as a rough starting point I recommend using the Katch-McArdle formula and activity multipliers below to estimate daily calorie expenditure.

Katch-McArdle formula:

• For men and women (metric): 370 + (21.6 x lean mass in kg)
• For men and women (standard): 370 + (9.82 x lean mass in lbs)

Activity multipliers:

• 1.2 – Sedentary: Little or no physical activity.
• 1.375 – Lightly Active: Light physical activity 1-3 days per week.
• 1.55 – Moderately Active: Moderate physical activity 3-5 days per week.
• 1.725 – Very Active: Hard physical activity 6-7 days per week.
• 1.9 – Extremely Active: Hard daily physical activity and hard physical work

Keep in mind this just gives you an estimated starting point. No formula will give you accurate measurement and even indirect calorimetry is only an estimate at best. Ultimately, whether you’re eating to lose fat or gain muscle, you will have to adjust your intake of everything based on how your body responds.

Macronutrient Ratios

There is no best macronutrient ratio. What proportion of macronutrients is optimum depends on the individual, their goal, and other factors. When eating to lose fat you may reduce calories while maintaining the same or higher protein and fat intake, resulting in a very different macronutrient ratio than when you eat primarily to gain muscle mass. The amount of carbohydrate an individual will perform or look best on can vary significantly due to genetics and activity levels.

Like most things, what is optimal varies between individuals and requires some experimentation to fine tune.

Protein

If you’re consistently doing the kind of heavy, high intensity training recommended on this web site I recommend consuming between 1 and 1.5 grams of protein per pound of lean body mass per day, or at least around a gram of protein per pound of body weight assuming you are moderately lean.

This is particularly important when dieting. If you cut calories, don’t cut everything proportionally.  If anything, aim a little higher with protein when trying to lose fat. It provides greater satiety than fat or carbohydrate and although the effect is very slight, results in a little greater thermic response.

There is no need to go nuts with it either. More probably won’t hurt, but eating more than 1.5 grams per pound of lean body mass probably daily won’t improve your gains either.

Fat

Fat is necessary for the production of essential hormones including testosterone, the absorption of fat-soluble vitamins, and provides energy for long-duration activities. Consume mostly unsaturated fats and limit saturated fats due to their association with cardiovascular disease. Strictly limit or avoid the trans fats found in many processed foods.

Carbohydrate

Carbohydrates provide energy for physical performance and support brain function, and aid in recovery from exercise by replenishing muscle glycogen stores. Contrary to the claims of some fad diet zealots, carbohydrates won’t make you fat if you’re not overeating. The appropriate amount depends on your goals and your individual response, and what you find easiest to adhere to.

Keep track of what you’re eating and how your body responds and and adjust accordingly.

Although it is possible to gain muscle mass on a low carb diet, at least moderate carbohydrate intakes seem to help and testosterone levels may also be reduced if carbohydrate intake is too low, along with cortisol levels increasing. Additionally, muscle glycogen levels appear to be maintained better on at least moderate carb intakes and post workout carbohydrate intake helps with recovery.

The majority of your carbohydrate should come from whole and minimally processed foods, including vegetables, fruits, grains, and legumes. Limit intake of heavily processed, hyper palatable foods loaded with simple sugars.

Grains and Legumes

Unless you have celiac disease eating small to moderate amounts of grains and legumes is not harmful. However, these are calorie dense, so you need to be mindful of portions.

Dairy

Unless you have lactose or casein intolerance dairy products aren’t going to make you fat or kill you either. If you’re eating to lose fat I don’t recommend drinking your calories, although a little milk or cream in coffee isn’t going to kill you. If you’re eating to gain muscle whole milk and heavy cream are a good way to get plenty of calories.

Like I mentioned with regards to carbs, keep track of what you’re eating and how your body responds and and adjust accordingly.

Alcohol

While light, occasional social drinking isn’t going to kill you or make you fat I don’t recommend regular, heavy drinking. If you must drink, stick to spirits and dry wine with diet soda. If you’re eating to lose fat minimize your alcohol intake.

Artificial Sweeteners

In the amounts typically used artificial sweeteners are safe and do not contribute to fat gain.

Supplements

Most fat loss and bodybuilding supplements are a waste of money, although some people may benefit from supplementing with certain vitamins and minerals. I will address individual supplements separately in future posts.

Meal Timing and Frequency

It is not necessary to eat every 2 to 3 hours to maintain an elevated metabolic rate (thermic effect of food), control appetite or keep blood sugar levels even. It is also not necessary to limit yourself to eating only once or twice per day.

When and how often you eat depends on how much you’re eating and what is practical for you. Someone eating to lose fat might find it more satiating and more convenient to eat 2 or 3 moderate sized meals than to eat 6 to 8 tiny snacks throughout the day, while someone eating to gain muscle might find it easier to eat a higher number of moderate sized meals than to force down a few huge meals per day.

Break your total food intake into comfortable sized meals and snacks that fit into your schedule.

Keeping Track

Weighing, measuring and counting calories is a huge pain in the ass. If you are overweight and trying to lose fat or underweight and trying to put on muscle it isn’t necessary to be super strict as long as you are at least somewhat conscious of portion sizes and eating in a manner appropriate to your goals. If, however, you already have a very low body fat and are trying to get down to a mid to low single digit bodyfat percent while maintaining lean body mass or you’re trying to maximize lean body mass while minimizing fat gain you’ll need to be a bit more precise, which requires weighing or measuring and recording food intake as well as keeping track of changes in weight, body composition and measurements.

Recently I’ve written a few things here and had discussions on rep speed and workout volume with a few people, and just wanted to mention a few things people should consider regarding rep speed, time under load, and the effect on relative workout volume.

Earlier I did shrug bar deadlifts, weighted dips, arm curls, calf raise, and a set with each hand on the Ivanko Super Gripper. Six sets total, 51 reps, in under 10:13. This Heavy Duty style workout is pretty short, even as HIT workouts go. Compared to a typical bodybuilding routine this is really short.

Or is it?

On average, I take around ten or more seconds to perform a rep; about a four second positive, a brief pause at the top of simple and compound pulling movements, about a four second negative, and a slow, controlled turnaround at the bottom. So 51 reps equals around seven minutes cumulative time under load.

A typical Nautilus style HIT workout might include one set of eight to twelve reps of a dozen exercises. Performed using a similar speed of movement the cumulative time under load would be around sixteen minutes.

A typical bodybuilding routine might include three or four sets of ten reps of up to a dozen exercises, or between 360 and 480 reps. Performed at typical speeds of around two seconds per rep, this would only add up to a cumulative time under load between 12 and 16 minutes.

Not much of a difference in time under load.

And two seconds is being really, really generous. I recently filmed one of my experimental subject’s workouts. Everything was going smoothly until I banged my head on the dipping handles of the Nautilus Omni Multi Exercise while setting it up. I watched the video afterwards to see if it was noticeable and even while watching at 4x speed searching for that part Joe still appeared to be moving more slowly and with better control than most people do in the gym.

So, assuming an average rep duration of two seconds is erring on the high side.

The total time under load for the hypothetical “high volume” bodybuilding workout may actually be lower than a typical Nautilus style HIT workout. Other than the quality of muscular loading, the biggest difference is the number of movements and the work/rest intervals. Comparing time under load to total time, the HIT workout has a much higher density of work.

There would be little rest between exercises in the Nautilus style workout. Assuming an average of ten reps per set, or around 80 seconds, and about 30 seconds to get out of one machine, get to, set up and enter the next, you’d be looking at a total workout time under 22 minutes.

With the typical bodybuilding routine, the total set time might average around 20 seconds, but the rest intervals tend to be on the longer side, usually 90 seconds or more unless pre-exhaust, supersetting or giant-setting is performed. With a 90 second rest interval, a 48 set workout would take around an hour and a half.

Why am I thinking about this?

After years following typical bodybuilding routines with little to show for it I made the best gains of my life following Mike Mentzer’s Heavy Duty program, training twice a week doing only a few exercises. Then I started doing SuperSlow, following Ken’s 1992 guidelines and over time lost size.

I was doing about the same number of exercises for about the same number of reps (four to eight), and at a similar frequency, so what was the problem?

The time under load. Averaging six reps per exercise at a 10/10 cadence and following each set with a  ten second static for “thorough inroad”  I was averaging over two minutes per exercise and over twelve minutes per workout. Two problems with this – the total time under load was around double, and since the sets were lasting two minutes straight I was not handling near as much weight and not putting nearly as much tension on the muscles.

The solution? I cut back to only two or three reps to bring the time under load down to under a minute. My results immediately improved.

Although entirely subjective, the sets also felt very different. I felt as though the exercises were more a challenge of strength than a stamina.

This presented a problem when I stopped working for Ken Hutchins and started doing some of my workouts at a local gym. When performing SuperSlow on equipment without resistance curves designed specifically for very slow rep speed, or when using free weights, sticking points that would normally feel like speed bumps became small hills. Even with a good understanding of strength curves and the moment-arms involved in free weight exercises, when you’re moving extremely slowly you spend a lot more time going through those sticking points and tend to get stuck there consistently. Increasing to a more moderate speed eliminated this problem while still allowing me to maintain proper body position and relatively strict form.

What’s the point?

There are several.

Volume is about more than the number of sets and reps. It is also a matter of time under tension, which must be considered if you are going to try using a slower or faster rep speed. It is also about the amount of muscle being worked – a deadlift places a much greater demand on the body than a wrist curl.

There is such a thing as too slow if you don’t have equipment that has very good resistance curves. You should never move very fast in exercise, but you may need to move less slowly when using less than optimal equipment or you might rob yourself of a few productive reps because you couldn’t get past a small “speed bump” of a sticking point. Understanding how to perform free weight exercises to balance the resistance and strength curves helps but not as much if you’re going really slowly.

Even if you have equipment with ideal resistance curves like Ken Hutchins’ SuperSlow machines or retrofitted Nautlilus and MedX, it isn’t necessary to move extremely slowly. You’ve got to move slowly enough to be able to maintain reasonably strict form, turnaround smoothly, etc., but that’s about it. Beyond that there is little additional benefit for most people. Of course, what is slow enough will vary between individuals depending on physical condition, motor ability, skill in the particular exercise, etc. Someone with joint problems and poor motor ability who is not skilled in the performance of a particular exercise may need to perform it considerably more slowly than someone in perfect physical condition with excellent motor ability and who is highly skilled in performing the exercise.

A reader recently sent me a link to a post on a HIT blog recommending fast repetition speeds and claiming they were necessary to recruit the high threshold, fast twitch motor units. Although I just posted a Q&A on repetition speed, motor unit recruitment and stimulation last week and am probably just repeating myself I figured I would post my responses here for those interested.

The specific statements in his post I responded to were:

Type II muscles fibers are responsible for explosive/ballistic movements and stimulating muscle growth.

and

Every rep you should aim to accelerate it at the greatest velocity possible while still maintaining control of it.

and

You can use moderate weight as long as you keep in mind that acceleration is key. It won’t be until the last few reps, near failing, that those high threshold motor units are really fatigued which will lead to your gains.

Normally I would ignore this since the internet is full of bad training advice and if I tried to address all of it I wouldn’t have time for anything else. However, since this was on a HIT web site I felt compelled to respond. The following was my initial response to the above comments:

I’m surprised and disappointed to see such bad advice on a HIT site.

High levels of acceleration are not necessary to recruit the high threshold IIB fibers. Even with loads as low as 60% of 1RM all the motor units in the primary muscles in an exercise will be recruited within a few reps after which force is maintained despite fatigue by increased rate coding.

Whether you move slowly or quickly, as long as you use at least a moderately heavy weight ALL of the motor units will be recruited.

Also, the type II fibers are not responsible for explosive movements. The “fast” and “slow” in “fast twitch” and “slow twitch” refers to the time in ms it takes a fiber to reach it’s maximum tension, not the speed of movement the fiber is capable of producing. The difference in twitch speed between slow and fast twitch is less than 1/10th of a second. Slow twitch fibers can produce rapid movements and fast twitch fibers will be involved in even extremely slow or isometric movements as long as there is adequate resistance.

He replied,

Drew,

I was advocating higher levels of acceleration when using submaximal weights for the sole reason of generating more total force which would result in the greatest recruitment of type 2 fibers. Type 2 being responsible for the most hypertrophy. Moving more slowly, even though utilizing all fiber types, would create far less total force than a faster concentric pace not fatiguing those HI motor units optimally.

The point of calling them fast twitch is because they contract quicker than do slow twitch. I looked in 2 sources and they say fast contract up to 10x quicker than do slow.

During your entire rant, you neglect to mention anything about the size principle. Making your argument about how slow and fast twitch fibers don’t really differ that much flawed. When talking about weight lifting and producing relatively large forces, we are mainly talking about fast twitch even though slow twitch are still active.

I honestly don’t care if you agree with me or not. Yuri Verkhoshansky, Im sure you know who that is cuz you seem to know everything sees shit the same way I do. Here’s a exerpt from Supertraining:

“Further research reveals that this high intensity is not necessarily dependent on the use of 1RM or near 1RM loads, but the degree to which the relevant muscle fibres are recruited during the effort. In this respect, the terms fast twitch and slow twitch do not necessarily mean that fast movements recruit exclusively FT fibres and slow movements ST fibres. To analyze the involvement of the different fibre types, it is vital to determine the forece that needs to be produced. If large acceleration of the load is involved, Newtown’s Second Law of Motion decrees that the resulting force will be large. This, the maximal force generated during the rapid acceleration of a 100kg bench press easily can exceed the maximal force produced during a slowly accelerated 150kg bench press. Both a small load accelerated rapidly and a heavy load accelerated slowly strongly involve the FT fibres….”

I responded,

A higher rate of acceleration would result in a greater peak (momentary) force, followed by a proportional decrease in force as result of kinetic energy imparted to the moving bar or weights. The average force would be approximately the same – the difference is, with a slower movement the force is more consistent over the full range of motion.

Additionally, due to greater cross-bridging a muscle is capable of contracting with more force at slower velocities (force/velocity curve) during concentric contraction.

The best way to increase force is not to rapidly accelerate, but to simply use a heavier weight. Doing so increases the tension over the full range of the exercise and not just during the initial acceleration.

The reason they’re called fast “twitch” is because the twitch speed, or time it takes the fiber to reach maximum tension is faster – not the resulting speed of movement. If your sources say otherwise, they’re wrong. In Karla Punkt’s Fibre Types in Skeletal Muscles, on page 10 there is a table which includes the twitch times in ms: 40-90 for fast, 90-140 for slow. On average, this is a difference of about 50 ms, or 0.05 seconds.

Fast twitch motor units within a muscle are larger and as a result capable of producing greater force thus greater acceleration, but this is because of their size not necessarily their physiology. It is not necessary to move quickly to recruit them, however, only to use an adequately heavy weight.

I didn’t mention anything about the size principle because it wasn’t necessary for the point I was making, nor did I say the fibers don’t really differ. I said the speed of movement they are capable of producing does not differ and the average difference in twitch speed or rate of force development is less than most make it out to be (when they make a distinction at all).

As for the quote from Verkhoshansky, while the maximum force generated during a rapid acceleration of a 100kg bench press can exceed the maximum force producing during a slow 150kg bench press, it will only do so briefly and will be followed by a significant reduction in force. The average force over the full range of motion would be higher for the 150.

With the exception of practicing competitive lifts there is no reason to recommend moving quickly during exercise. Fast reps are not necessary to recruit the type IIB fibers, provide no advantage slow reps with adequate resistance, and have the disadvantage of producing an inconsistent level of tension over the range of motion, not to mention an increased risk of injury.

I give him partial credit for qualifying his recommendation to accelerate at the greatest velocity possible with the words “… while still maintaining control of it. ” Although, technically, this is not bad advice if the emphasis is on control, in practice it tends to result in sloppy and relatively ineffective performance. There is no benefit to moving faster during exercise and no disadvantage to moving more slowly so it is best to err on the slow side.

During the first few repetitions of an exercise the attempted speed of movement should be at least moderately slow. Specifically, slow enough that you are able to:

1. Maintain strict body positioning and alignment.
2. Reverse direction smoothly with no bouncing, yanking, jerking or heaving.
3. Focus on intensely contracting the target muscles over the full range of the exercise.

As you fatigue the reps will become progressively slower. At this point you should attempt to gradually increase acceleration, trying to move faster but without altering body positioning and without jerking or heaving the weight. By this point it will be impossible for you to move faster if you maintain proper form and attempting to do so in a controlled manner will increase the intensity of contraction.

You should not, however, attempt to accelerate as much as possible at the beginning of an exercise or when using a weight that would allow you to move very rapidly.

I have not returned to the site after posting my second comment and have no interest in continuing the discussion there. I have too many other projects to work on to be writing on other people’s web sites at the moment. For now I’ll be taking Nautilus inventor Arthur Jones advice:

“The next time somebody suggests that you move suddenly during any form of exercise or testing, smile and walk away, because you are talking to a fool.”

I’m probably starting to sound like a broken record, but if you don’t take anything else away from anything I’ve written here remember this; the keys to progress are to train very hard, very briefly, and give your body adequate time for recovery between workouts. Stated differently, the worst mistakes you can make with your training are to do too much, too often, but not hard enough.

Unfortunately, these three mistakes are the most common.

It’s not unusual for people who don’t know any better to boast to friends and acquaintances about the amount of time they spend in the gym or “working out” each week. Never mind that most of their time is spent looking at themselves in the mirror or socializing, they’re putting in the hours, and in their minds that equates to dedication.

While dedication is usually admirable, in this case it is just misguided. They are operating under the assumption results from exercise are proportional to the time invested or the volume of work performed, and that by spending more time they will produce greater results. Many also believe it is necessary to perform several different types of activities to improve different aspects of fitness; resistance training for muscular strength and endurance, steady-state activities or interval training for cardiovascular and metabolic conditioning, stretching for flexibility, etc.

All of this adds up to a lot of weekly hours in the gym.

On the low end, the American College of Sports Medicine’s current physical activity guidelines recommend at least 30 minutes of moderate-intensity steady-state activity five days a week (60 to 90 for those needing to lose fat) and 30 minutes of strength training twice weekly, for a total of around 4 hours per week. On the higher end, some bodybuilding programs require up to 10 hours or more.

Whether you’re a bodybuilder or athlete or someone just trying to get fit or lose a bit of fat, the actual amount of weekly exercise required for optimum results is far less.

How much less? On average only four hours a month. Not four hours a week, but four hours a month. And this assumes you’re training in a gym during peak hours where crowds and inefficient equipment layouts increase the time it should take to get through a workout. If you go during off-peak hours, have a home gym or have personal training in a private high intensity training studio you can cut that time by half or more.

There are several reasons for this:

1. Exercise does not directly produce any improvements, it stimulates the body to produce them as an adaptive response. For this to occur the body must be allowed adequate time to recover from the stress of the workout and produce the improvements. Depending on the individual, the intensity of training and other factors this process can require anywhere from a few days to a week or longer. If too much exercise is done too frequently the cumulative stress will exceed body’s ability to recover and adapt and rather than improve you will plateau or get weaker.
2. The degree to which the body is stimulated to improve is proportional to how intensely you train – not how much you do or how long you work out – and there is an inverse relationship between the intensity and volume of exercise. The harder you train the less is required and the longer the recovery needed between workouts.
3. High intensity strength training will improve cardiovascular and metabolic conditioning better than moderate-intensity steady-state activity making it unnecessary to perform additional activities for that purpose.
4. As long as exercises for all the major muscle groups and involving all the major joints are performed through a full range of motion flexibility will also be improved making additional stretching unnecessary.
5. Neither moderate-intensity steady-state or high intensity interval training (AKA “cardio”) are necessary for or make a significant contribution to fat loss. The muscle-preserving, metabolic and hormonal effects of even very brief and infrequent high intensity strength training contribute far more to improving body composition.

How can this be done in only four hours a month? Consider the following basic workouts, which address all major muscle groups.

With free weights and body weight:

1. Barbell Squat
2. Chin Up
3. Barbell Press
4. Dumbbell One-Legged Calf Raise
5. Barbell Row
6. Dip or Bench Press
7. Stiff-Legged Deadlift
8. Weighted Crunch
9. Barbell Wrist Curl
10. Barbell Wrist Extension

With machines:

1. Leg Press
2. Close, Underhand-Grip Pulldown
3. Shoulder Press
4. Calf Raise
5. Seated Row
6. Chest Press or Seated Dip
7. Back Extension
8. Abdominal Flexion
9. Wrist Curl (Nautilus Super Forearm or Cable Machine)
10. Wrist Extension(Nautilus Super Forearm or Cable Machine)

Only one set of each exercise is necessary. If the first set is done properly more sets will not improve your results but will increase fatigue and add to the limited amount of stress your body can recover from.

Using a slow, controlled speed of movement, a set of 7 to 10 repetitions should only take around 50 to 80 seconds, averaging a little over one minute per exercise. Even if you rest for two full minutes between exercises, your total workout time would be just under 30 minutes. Done twice weekly – which is plenty if you’re training hard enough – this amounts to less than four hours a month.

If you work out at home or train in a private studio the rest and set-up time between exercises can be reduced significantly, cutting the time required for the above workouts down to less than 15 minutes. Advanced trainees or those working out with an experienced HIT trainer may require even fewer exercises, in some cases as little as 3 to 5.

What can a person expect from training only four hours a month?

Timothy Ferriss, author of The 4-Hour Work Week gained 34 pounds of muscle in four weeks using this approach, with only four hours of training. He covers his training and diet in detail in his upcoming book The 4-Hour Body, which also features yours truly in the section on abdominal training.

When I first started doing high intensity training using Mike Mentzer’s Heavy Duty I also trained twice weekly on even shorter routines and gained nearly 30 pounds of muscle over a period of six months. I’ve had several male clients consistently gain a pound of muscle or more weekly over their first few months of training. One man I trained gained 8 pounds of muscle during his first three weeks of training.

I’ve had men and women lose huge amounts of fat training less than four hours a month as well, including one woman who lost over 100 pounds in a year and a man who lost over 30 pounds in two months.

Many people have been getting excellent results following the Body by Science program which involves once weekly 12 minute workouts. That’s less than 10 hours per year. And they’re getting better results than people training as many hours per week following conventional bodybuilding programs.

I train twice weekly, alternating between the following workouts, each of which usually takes about 10 to 12 minutes to complete including set up but can be finished in under 6 minutes if I rush between exercises. The specialization routine is included in every second or third rotation.

Workout A:

1. Barbell Squat
2. Weighted Chin Up (Nautilus Omni Multi Exercise)
3. Standing Barbell Press
4. Wrist Curl (Nautilus OME)
5. Wrist Extension(Nautilus OME)

Workout B:

1. Shrug Bar Deadlift
2. Weighted Dip(Nautilus OME)
3. Arm Curl(Nautilus OME)
4. Standing Calf Raise (Nautilus OME)
5. Ivanko Super Gripper

Arm/Shoulder Specialization:

1. Negative-Only Weighted Chin Ups (10 second negatives)
2. Negative-Only Weighted Dips (10 second negatives)
3. Arm Curls
4. Tricep Extensions
5. Dumbbell Lateral Raise

Not including the minute or so it takes to load the bars or set up the multi-exercise, the total time for each of the above workouts the last cycle was 10:00, 9:48 and 9:21. My total training time for a month is less than 90 minutes.

If you’re not currently working out because you thought you don’t have the time, now you know you do. If you still have doubts the only thing you have to lose by trying for just one month is four hours. What you have to gain, however, is invaluable. Proper exercise can literally change your life.

If you’re currently spending several hours a week in the gym and not just because you enjoy the social atmosphere (some people just like hanging out in gyms, which is fine) take a week or two off (you’re probably overtrained and need the recovery time) then drop the “cardio” and just do two hard strength training workouts a week for a month or two instead. If you don’t get better results (you will) or if you’re really addicted to the endorphin fix of “cardio” or really do just like hanging out at the gym you can always go back to what you were doing before.

However, if you’ve been working out for more than an hour or two a day most days of the week you have even more to gain from cutting back than the people who haven’t been working out will gain from starting; not only will your results improve, you’ll also get back irreplaceable time that can be better spent with family and friends or pursuing other interests.

This Q&A is a response to several questions I’ve recently received. Since they’re all related I’m going to answer them together.

Since intentionally moving slowly during exercise involves less than a maximum effort wouldn’t it reduce motor unit recruitment and the effectiveness of the exercise?

No. Motor unit recruitment is determined by the amount of force the muscles are required to produce in order of size starting with the smallest motor units with the fewest fibers and ending with the largest with the most fibers. Regardless of the speed of movement if the weight is heavy enough (adequate to cause momentary muscular failure within a minute or two) you will recruit all of the motor units in the muscles being worked within a few reps. After all of the motor units have been recruited and are fatiguing further increases in force production are achieved by increasing rate-coding (the frequency of the signal to the motor units to contract).

Even if you are intentionally moving slowly at first, if the weight is heavy enough you will eventually have to contract as intensely as possible to lift it. Effort is relative to your momentary strength. As fatigue reduces your strength during an exercise the weight requires a larger percentage of your mometary ability which is why it feels progressively heavier. For example, a weight that only requires is 80% of your available strength at the beginning of an exercise will require an 89% effort at the moment fatigue has reduced your strength by 10% (80/90 = 0.89 or 89%) and when fatigue has reduced your strength by 20% you are contracting with 100% of your momentary strength just to hold the weight (80/80 = 1 or 100%). By this point in the exercise every motor unit in the working muscles has already been involved for a while.

My personal trainer told me I have to lift explosively to recruit the high-threshold type IIB motor units which have the greatest potential for hypertrophy and that slow reps only recruit the slow-twitch, type I fibers.

Your trainer doesn’t know what he’s talking about.

The terms “fast” and “slow” in fast and slow twitch muscle fibers refer to the twitch speed – how quickly the fibers can reach maximum tension – not the speed of movement they produce. Fast twitch fibers reach maximum tension between around 50 and 80 milliseconds, slow around 100 to 200 milliseconds. On average this is a difference of only 85 ms, less than one hundredth of a second. The biggest difference between fast and slow twitch fibers is the relative fatigue and recovery rates; fast twitch fibers fatigue more rapidly and recover more slowly, slow twitch fibers fatigue more slowly and recover more rapidly.

Contrary to popular misinterpretation of their names, your muscles’ slow twitch fibers are capable of producing very fast movements and your fast twitch fibers will be recruited during even the slowest movements if the resistance is high enough.

For example, an isometric contraction is about as slow as it gets during exercise – you don’t move at all. However, when performing timed static contractions or heavy static holds you will recruit even the high threshold fast twitch motor units because the muscles need to recruit all of their motor units to produce the required amount of force.

Moving fast is neither necessary for recruiting the fast twitch motor units nor more effective for that purpose. The only thing moving faster tends to do is compromise form and increase the risk of injury. The idea one must “train fast to be fast” or that “slow training makes you slow” is nonsense.

My coach said I have to lift explosively to improve power. How am I supposed to increase my power for (football, martial arts, golf, etc.) if I don’t train explosively?

Your coach doesn’t know what he’s talking about. I’m guessing he also told you power cleans were the best way to improve your ability to explode off the line, punch hard, increase the force of your golf swing, and become rich and good looking, which would make him doubly ignorant.

If you want to become more powerful in general you just have to train to become stronger, and you can do that training fast or slow. Power is the amount of work you can perform over a period of time. Work is force x displacement. A stronger muscle can produce more force, meaning you can either move a greater mass over the same distance in the same period of time, move the same mass over more distance in the same period of time, or move the same mass over the same distance in less time.

For example, if the most you can lift in an exercise one time is 200 pounds you won’t be able to lift it very quickly. If you increase your strength so that you can lift 250 pounds in that exercise, you will be able to lift 200 pounds more quickly.

If you want to become more powerful in a specific movement you must also learn and practice the skill of performing that movement in a way that makes efficient use of the strength of the involved muscles. Skill improvement is very specific; to become more skilled at a movement you must practice that movement, not something that somewhat resembles it, not a similar movement while holding a weight or with something heavier than you would normally use, but the exact movement.

Many well-meaning but misinformed coaches and trainers will tell you doing power cleans will result in a transfer of explosiveness to just about any other activity. They’re wrong. The only thing power cleans are good for is improving your ability to perform power cleans. They are relatively ineffective for improving the strength of the involved muscles when compared to other exercises, have a greater risk of injury, and will do nothing at all to improve your skill in any other movement. If you are a competitive Olympic lifter you must perform cleans as part of your training for the clean and jerk, but there is no good reason for anyone else to do them.

“Bodybuilders are Confused” is the title of the first chapter in Mike Mentzer’s book Heavy Duty which describes the nonsense and conflicting information most bodybuilders must sort through in their quest for valid information on building bigger muscles. In it, Mike explains how commercial interests, tradition, and a lack of critical thinking skills and understanding of the scientific method have resulted in bodybuilders being exposed to more misinformation than truth.

Unfortunately, this is not limited to bodybuilders. Most of what the general public believes about exercise is outright wrong, and much of that is due to the same types of commercial interests, traditions and thinking errors. To make matters worse, most of the people on the figurative front lines who should be debunking the myths and educating the public about proper exercise – personal trainers – are the most confused of all.

In October of 2009 I resigned from a training position at a high profile studio in Central Florida because the owner hired a new manager who – typical of most personal trainers – believed in a lot of silly bullshit. During our initial meeting he said he planned for us to start offering nonsense like Pilates and plyometrics in addition to our high intensity strength training program at which point I informed him these things were “crap” and if he compromised our HIT program in any way I would walk. He said it wasn’t up for debate, so three days later I handed in my resignation and took my clients elsewhere.

That “elsewhere” was another personal training studio which rented to independent contractors. There, I was surrounded by typical personal trainers who  also believed in and practiced a lot of silly bullshit. They were all very nice people, well-meaning and sincere, but they were also sincerely misinformed and most of what was being offered as personal training there was an ineffective waste of time at best and outright malpractice at worst. Although I was knee deep in it at least I was not being forced to teach it, and some of the things the other trainers did with their clients served as excellent examples for teaching now not to perform an exercise.

I have no illusions about being able to fix this or even being able to convince a large number of people of how to train properly. I have no intention of trying. The best I can hope for is if I present the facts and explain things clearly that those of you with the critical thinking skills to get it and the motivation to apply it benefit from what I write here and maybe teach it to others who might also benefit.

With that in mind I would like to share a discussion I had on a nutrition forum a while back with a very confused personal trainer we’ll call “CPT” for short. In most cases, arguing with idiots on the internet is a complete waste of time – you’re not going to convince them of anything. However, if you argue with the intent of informing others reading the debate rather than “winning” against the idiot some readers will benefit and at the very least debate can sharpen your own understanding of and ability to explain the subject. So, in hopes some of the readers get something useful from this, here are all of my comments along with CPTs statements and responses, unedited except for spelling.

March, 2009 – Discussion with Confused Personal Trainer (CPT)

CPT: Once again we hear the theories of Arthur Jones from the lips of yet another marketer.

Remember that the true talent of Arthur Jones was not growing muscle, it was growing companies. Jones grew Nautilus and sold it for millions. Jones grew MedX and sold it for millions. His greatest talent was in convincing people that they needed his expensive machinery to get them fit.

Now we have another generation saying the same old tired marketing line. Come train on my expensive equipment in a “scientific” manner, blah, blah, blah. Not interested. Not needed.

Plain old free weight iron lifting can build muscle just fine. Simpler, cheaper and a LOT less boring.

Drew Baye: I find it interesting that you put scientific in quotes, implying the principles are not, when the majority of research supports Jones’s exercise recommendations. Yes, Jones was talented at growing companies, but he also knew how to grow muscle.

You apparently know very little about Arthur Jones. He never said his machines were necessary for building muscle, only that they were more efficient.

Whether free weights are less boring is a matter of opinion.

CPT: And surprisingly, safer as well. Most gym injuries occur using machines. People get lulled into complacency on machines and fail to observe good safety practices and often get injured. People know that throwing pig iron up in the air is dangerous, so they tend to be more careful.

Drew Baye: References, please. If you’re going to make statements like that you need to be able to back them up. Frankly, I don’t believe you, because in my experience this is not the case.

Injuries occur for a variety of reasons, but most of these are related to improper use, rather than the equipment itself. This is not a problem with machines, it is a user error. People can hurt themselves just as easily, and in many cases more seriously with a barbell if not properly instructed.

CPT: Lift smart, lift big, lift short, go home. There’s no magic formula that makes it work perfectly in 12 minutes a week. But that kind of talk sure sold a whole lot of Nautilus gym memberships!

Drew Baye: Whether 12 minutes a week is adequate depends on a lot of factors, not the least of which are individual genetics and intensity of training. There’s nothing “magic” about it – it’s pretty basic physiology, and a lot people have produced very good results using this kind of training.

CPT: I think what is so amazing is that anyone believes this. Doug described using specially modified weight equipment to do the workouts.

Drew Baye: If you read the book, you’d know they also cover using the method with barbells.

CPT: Will twelve minutes per week give you the “best shape your genes will allow you”? I highly doubt it.

Drew Baye: A quote from Marcus Aurelius:

“Because your own strength is unequal to the task, do not assume that it is beyond the powers of man; but if anything is within the powers and province of man, believe that it is within your own compass also.”

Perhaps you doubt it because your methods are far less time-efficient, but it is certainly possible. I have many clients who train once weekly who’s workouts are around 12 to 15 minutes (6 to 8 exercises) who have made better progress training with me than with other trainers locally who use more typical training volume and frequency.

I used a once-weekly, six-exercise routine lasting less than 12 minutes in preparation for a bodybuilding competition in ’95:

One set to failure using enough weight to keep the TUL between 90 and 120 seconds, no rest between exercises:

Stiff Legged Barbell Deadlift
Hammer Strength Leg Press
Hammer Strength Pulldown
Hammer Strength Chest Press
Hammer Strength Low Row
Cybex Plate-Loaded Calf Raise

CPT: Kris R, “Oh sure, 12 minutes sounds like a magic bullet but anyone who is trying to sell something has to have a hook of some sort.”

If you’re ok with that kind of marketing, that’s up to you. I’m not buying it.

Drew Baye: The publisher usually comes up with this. When you see things on book covers like “gain up to X pounds of muscle…” or “…in only Y minutes per week” chances are some marketing person wrote it. Nonetheless, there are people training less than that getting good results.

CPT: Yeah, it IS about tolerance… and lack thereof. You mentioned not knowing who Arthur Jones was, so I suppose I need to back up. The HIT (High Intensity Training) guys (like Arthur Jones of Nautilus) and the subset of super slow speed HIT guys came out decades ago and soured everybody with their ‘our way or the highway’ attitude. There was a lot of ‘this is the ONLY scientific way to train’ kind of talk floating around and the lack of tolerance turned many people off to these ways of training. That and the fact that many people tried it and had mediocre results from it.

Drew Baye: People don’t like being told they’re wrong, and Arthur and many who were associated with him weren’t very tactful when addressing the myths and fallacies held by many in the fitness industry. This made them unpopular with a lot of people. No argument there.

While you claim many people had mediocre results from it, in the sixteen years I’ve been training people I’ve seen the opposite. The people I’ve trained often came to me after being dissatisfied with the results they got working with other trainers using more mainstream methods.

CPT: Decades have passed and the benefits of high speed power training continue to get better and better documented. Meanwhile, the super slow HIT crowd continue to talk like they’ve got the best thing ever invented and you’d have to be dumb to train any other way. The evidence in the scientific literature for their arguments is weak from what I’ve seen.

Drew Baye: More unsupported statements.

Research does not show an advantage to “high speed” or “power” training – and the scientific literature for slower, controlled speeds is anything but weak. See

Carpinelli RN, Otto RM, Winett RA. A Critical Analysis of the ACSM Position Stand on Resistance Training: Insufficient Evidence to Support Recommended Training Protocols. Journal of Exercise Physiology Online 2004;7(3):1-60

Smith D, Bruce-Low, S. Strength Training Methods and The Work of Arthur Jones. Journal of Exercise Physiology Online 2004;7(6): 52-68

CPT: I specialize in training seniors, so I’m especially sensitive to maximizing their speed, since they only have a few hundred milliseconds to catch themselves during a fall. Training them to move slow makes no sense, and recent literature backs up training them fast to maximize power production. Power = Strength X Speed.

Drew Baye: Using fast repetitions to help prevent a person from being injured is about as ironic as it gets.

Slow repetition speed during exercise does not make a person slow during other activities, and fast reps are not necessary to improve power production. Power does not equal strength x speed, it equals work (force x displacement) divided by time.

If you improve a persons strength (force producing capacity) you will improve their ability to displace some mass (move their body to regain balance) in less time. You can get stronger using fast or slow speeds, but you’re less likely to injure someone during exercise using slower reps.

In my opinion, recommending fast movements during exercise to the elderly is malpractice.

CPT: For my clients, training methodology is more than just a style choice. I’d be remiss if I didn’t point out the hazards of training slow. Why waste training time maximizing strength with a method that doesn’t maximize speed when it’s speed that’s going to help you catch yourself during a slip before it becomes a fall?

Drew Baye: You’re remiss in not pointing out the hazards of training fast, mainly an increased likelyhood of injury either due to sloppy form or excessive force encountered during acceleration.

The skill of moving a weight during an exercise at a particular speed has no bearing on the skill of performing necessary adjustments in posture or other movements necessary to maintain or regain balance. There is nothing about performing fast repetitions as opposed to slow ones that contributes to an increase in speed in different movements.

CPT: I stop feeling tolerant when I see people recommending training methods that are blatantly insufficient at producing the power improvements my clients desperately need to live fulfilling, active later years. Remember, Dr. Atkins DIED from his slip and fall. Training methodology truly can be a life or death choice.

Drew Baye: Yes it can, which is why I would strongly caution the elderly not to work with any trainer recommending a fast speed of movement during exercise.

As for power production, I have many clients over 60 who are avid golfers, including one in his mid 80s, who have significantly increased their driving distance (a movement requiring significant power output) since they started training with me, and using slow reps. If slow reps were “blatantly insufficient at producing power improvements” this would not be the case.

The only thing that appears to be “blatantly insufficient” here is your understanding of exercise.

CPT: Not interested. Calling it “Power” of Ten is a misnomer. Power = Strength X Speed. You’re not going to get powerful moving slow.

Drew Baye: Sure you are. If it makes you stronger, it will make you more powerful. Regardless of the speed of movement that stimulated the increase in strength, if a muscle is stronger it can produce more force, and if it can produce more force it can accelerate more quickly against some amount of resistance.

If your one rep maximum in an exercise is 100 pounds, you will not be able to move it very quickly. If you increase your one repetition maximum to 150 in that exercise, then you will find it much easier to move 100 pounds more quickly. It doesn’t matter if you got there with slow reps or fast reps – the stronger muscle will have higher potential power output. However, you’re less likely to get injured in the process using slower reps, and the majority of people have much, much better form when forced to slow down and focus more on how they’re moving.

CPT: Slow Burn does increase strength, while minimizing the effects of momentum and gravity. By minimizing the effects of momentum and gravity it prepares the body for nothing that exists in the real world. Real world useful strength is expressed through power. Power is the ability to explosively direct your strength as fast as possible. Strength/Power is what Rippetoe and Kilgore teach extremely well. I give Starting Strength my highest recommendation.

Drew Baye: Developing “real world, useful strength” does not require moving fast during exercise. It simply requires getting stronger. If you get stronger, you will be capable of higher power production (work per time), regardless of whether you got stronger using fast or slow movements.

The only thing moving fast during exercise does that moving slow doesn’t is improve your skill at moving fast during the specific exercises practiced. If you want to become faster in general, simply becoming stronger will improve this, because a stronger muscle can produce more force, meaning it can accelerate against resistance (effect of gravity on moving body parts or objects being acted on) more quickly. If you want to improve speed in a specific movement, you must first learn the most efficient way to perform the movement, then practice the movement, gradually increasing speed over time.

CPT: Time Under Load is a red herring. Plus it’s boring.

Move fast to build some power!

Drew Baye: Both time under load and repetition count are useful means of measuring exercise performance. Each have pros and cons and are useful for different things.

CPT: I would strongly caution the elderly not to work with any trainer who doesn’t keep up with the latest research:

Scandinavian Journal of Medicine & Science in Sports:Volume 18(6)December 2008p 773-782
Explosive heavy-resistance training in old and very old adults: changes in rapid muscle force, strength and power
P Caserotti, et al

These findings demonstrate that explosive-type heavy-resistance training seems to be safe and well tolerated in healthy women even in the eighth decade of life and elicits adaptive neuromuscular changes in selected physiological variables that are commonly associated with the risk of falls and disability in aged individuals.

Drew Baye: This is not proof that the same or better results could not have been produced using a lower, more controlled speed of movement, and with lower risk of injury over the long term.

CPT: I did. Strange you should bring it up since Carpinelli refutes both Super Slow repetition durations and extended Time Under Load manipulations of set length. The science you cite, specifically refutes your position:

No study using conventional exercise equipment reports any significant difference in muscular hypertrophy, power, or endurance as a result of manipulating repetition duration.

There is very little evidence to suggest that a specific time-under-load (e.g., 30s versus 90s) significantly impacts the increase in muscular strength, hypertrophy, power, or endurance.

So Carpinelli, who you cite to “support” your position, specifically says you are wasting your time bothering with long repetitions and set lengths.

Drew Baye: Carpinelli didn’t refute anything I said. I never said slow reps produced superior results, only that they were safer. All else being equal (results), it makes sense to use the safer method. The point in referencing this was to show that fast reps do not produce superior results, a position the paper does support.

I also made no claims about the superiority of free weights versus machines in producing results – I clarified Arthur’s position and pointed out the lack of support for your claim that they were more dangerous than free weights.

CPT: Power training is more effective than strength training for maintaining bone mineral density in postmenopausal women
Stengel, et al

Whereas the Power Training group maintained Bone Mineral Density at the spine and the total hip, the Strength Training group lost significantly at both sites.

During the resistance training, the Strength Training group used slow and the Power Training group fast movements; otherwise there were no training differences.

Drew Baye: There are also plenty of studies showing high intensity training produces significant increases in bone density, and that these results have to do with the loads used, rather than the speed.

I train several older women who’s bone density/bone mineral content improved significantly after starting high intensity strength training using slow repetition speeds.

CPT: One should not carelessly toss around accusations of malpractice when they train their clients using slow repetition speeds that can contribute to osteoporosis.

Drew Baye: There is nothing about slow repetition speeds that contributes to osteoporosis, and claiming such shows your ignorance on this subject. Like I said, I have trained many elderly women who have improved bone density considerably using slow repetition speeds, and MedX has done a large amount of research on this at the University of Florida, showing the same.

CPT: More from Stengel:

…a protocol with substantially higher loading variations generated by bending, tension, torsion, and compression demonstrated signi?cant exercise effects on Bone Mineral Density…

So apparently, by deloading the torque on the bone by slowing down the movement, Super Slow prevents the very strain that encourages bones to lay down new density.

Training slow’s a bug, not a feature!

Drew Baye: Slowing down the movement does not unload the muscles. To hold a weight motionless or lift it at a constant velocity requires a force equal to the load. Regardless of the speed of movement, if the velocity is constant, the effort produced by the muscles to lift X pounds averages out to the same.

The differences are due to acceleration, not the average velocity.

To accelerate it positively requires an increase in force proportional to the rate of acceleration. As a result of that acceleration, kinetic energy is imparted to the mass being moved. Eventually, you have to accelerate negatively (decelerate) during which the kinetic energy reduces the amount of force required to continue upwards movement. You encounter more force initially during the positive acceleration, and proportionally less during deceleration. The average force over the full range still ends up being the same.

The difference with a slower rep is less acceleration initially means a lower peak force (a good thing, since this is where injury is most likely to occur with fast reps) but the same average force over the ROM, and in fact, a more consistent tension over the full ROM.

If the weight is heavy enough, it doesn’t matter if you move it fast or slow, it’s going to stimulate improvements in bone density. The slower movement is less likely to cause injury, however.

Additionally, due to the force/velocity curve, a muscle is capable of producing more force when contracting at slower velocities, and thus handling more weight, and providing more benefit in terms of bone density.

I’d go into it in more detail right now, but I have to get back to work, training people safely 🙂

Drew Baye: A lot of these anecdotes about elderly people and explosive training can be attributed to what is called survivorship bias.

People who have dropped out of something due to injury or lack of success with it tend to not be counted or considered when comparisons are made, leading to the erroneous assumption that these “survivors” are representative of the norm, which they are not.

Will training with fast, explosive reps injure everybody? No. It is more likely to cause an injury, but it will not injure everyone. People who are not injured by it, for whatever reason, will then be held out as examples of it’s safety, which is misleading to the rest of the people, many whom may not share the traits or circumstances which allowed the “survivor” to avoid injury.

See http://en.wikipedia.org/wiki/Survivorship_bias

Doug McGuff also discusses this in Body by Science, explaining why examples and claims like the ones Ben provide here are misleading.

Drew Baye: CPT,

If you really want to get into dueling studies, I’m sure a half hour of digging through what I have on my hard drive and searching google scholar will pull up plenty refuting you. You’re not impressing or convincing any informed person here.

The fact of the matter is, the primary stimulus for improvements in bone density/bone mineral content, is the tension they are placed under during resistance training, and this can be done with slow or fast repetitions. Slower repetitions are safer, however, which is especially important when working with people with osteoporosis.

Like I said before, injury is caused when a tissue is exposed to a level of force exceeding its structural strength, and force increases with acceleration. While a weight that can be lifted with a slow, controlled manner will not impose a greater force on the involved tissues than they can handle, the resulting force peaks from attempting to rapidly accelerate such a weight can.

It is easier for people to maintain correct form when moving more slowly, and maintaining other aspects of form than speed is also important for avoiding injury.

It is not necessary to move quickly during exercise to improve the ability to move quickly (power) during other activities. I’m going to try to make this as simple as possible – try to follow:

Power is work divided by time. Work is displacement times force. A stronger muscle is capable of producing more force. Since work is the product of force and displacement, more force equals more work. More work per time equals more power. It doesn’t matter how you get the muscle stronger – fast or slow reps – if it is stronger, it is more powerful. It comes back to safety; if either are effective, the safer method is a better choice.

Keep in mind we’re talking about exercise. In practicing a specific athletic or vocational skill to become faster, then fast movement is necessary. This is different than exercise, however. You can improve your ability to punch quickly, for example, by practicing slowly at first while learning proper mechanics, but eventually you must practice fast, because you will move the way you practice during competition.

There is no positive transfer of skill between exercise movements and other movements however, even if they are similar. If an exercise makes you stronger, it makes you faster, but there is nothing in particular about moving fast during exercise that will make you any faster in other activities than moving slowly during exercise, and moving slowly during exercise will not make you slower either; there is no transfer of motor skill between exercise and other movements.

The only exception is if the exercise is the skill, such as in Olympic lifting and power lifting, in which case it must be practiced at the speed it will be performed in competition. This is where a lot of people get confused.

Say what you will about the relative merits of fast and slow reps (and everything in between), but in over 15 years of doing this professionally during which I’ve trained hundreds of people and have instructed tens of thousands of sessions I have never had a client injured because of moving slowly during exercise, and I know literally hundreds of instructors using similar methods, some for decades, who can say the same. Many of the people I have trained who have been injured during exercise prior to working with me, often when working with trainers who think like you, were injured as a result of performing exercises in a fast, sloppy manner (the two usually go hand in hand).

If the goal is to get the maximum benefit from exercise with the minimum risk of injury, slower repetitions are the way to go. One should at least move slowly enough to be able to reverse direction in a deliberate and controlled manner between the lifting and lowering movements without bouncing, jerking or yanking at the weight, and slowly enough to be able to stop instantly without further motion at any point during an exercise.

Drew Baye: I stay pretty current, and I have yet to see anything which would support the use of faster repetition speeds for any purpose. For every study showing some advantage of faster repetition speeds there are several showing no advantage or an advantage for slower reps.

Drew Baye: (Responding to being called “fanatical”) I’m not sure what’s fanatical about erring on the side of safety – this has been the reason for my recommendation of slow reps.

I would like to see you try to refute any of the basic physics discussed here so far. You haven’t, because you can’t.

You also have no response to the relationship between concentric contraction velocity and force production, because you can’t – it is a fact that muscles can produce more force when contracting at slower velocities, thus handle more weight, placing greater tension on the muscles, connective tissue and bones, resulting in a greater stimulus for improvement.

As for claiming Jones and the Mentzers were the last authorities on HIT, you show how little you know about the subject and its history. There are many people in exercise, medicine, physical therapy, athletics, etc. who I would consider experts and who continue to refine and educate people on high intensity training. Doug McGuff, the author of the book this discussion is about, is one of them.

Also, before you start making any more ignorant claims about Jones or the Mentzer’s, be aware that I knew Arthur Jones and Mike Mentzer personally. I was introduced to Mentzer through the owner of the gym I worked for during college, who was a phone client of his, and communicated with him regularly from then until his death in 2001. I was introduced to Arthur Jones by Jim Flanagan at a MedX seminar in Maitland, FL in 1997, and spoke with Arthur often between then and his death in 2007, including visiting him at his house in Ocala. Both were very generous with their time and knowledge and I owe them a great deal of gratitude, and will not let them be misrepresented in any way if I can help it.

Drew Baye: For those wanting references related to controlled versus explosive repetition speeds, I have two articles on my web site posted with the permission of the author, Ken Mannie, the strength and conditioning coach at Michigan State. Each are well referenced, and more importantly, well reasoned:

https://baye.com/explosive-training/

https://baye.com/exercises-equipment-modes-and-rep-duration-the-question-of-superiority/

CPT: What seems fanatical is the endless repetition of the safety of slow reps mantra without any evidence to back it up.

If this training method is so fantastically safe, you should get a break on your liability insurance, right? Surely you have reams of safety data since Arthur invented the Nautilus machines back in the 1970’s. Show us the safety data, Drew. Don’t tell us your opinions. Don’t lecture us about physics. That’s just a bunch a beatin’ around the bush.

Let’s see the safety studies that show hard endpoints of reduced injuries.

And don’t point me towards Ken Mannie’s creaky old review paper that cites 40 references and none of them is newer than 1993. That’s so last century.

Current safety studies please.

Drew Baye: A valid experiment is a valid experiment, and just because it is old doesn’t mean the information is invalid.

CPT: Quit changing the subject. Where’s the safety studies proving lifting slow is safer? Not physics explanations, not exercise physiology lectures; studies. Studies with hard end points of less injuries for your supposedly superior method. You and Serious and Dream keep saying that your way of training is safer and mine is more dangerous.

Nonsense. You have no such studies to point to. They don’t exist.

Your safety claim is pure vaporware and wishful thinking.

Drew Baye: CPT,

The physics explanations are more solid proof than any study or survey one could perform. This is very simple reasoning, based on irrefutable premises:

1. Injury results when a tissue is subjected to a level of force (strain, compression, shear, etc.) causing it to deform beyond its elastic limit.

2. The faster you accelerate during exercise, the greater the force input required (Newton’s second law)

3. For every action there is an equal and opposite reaction (Newton’s third law), which means, the more force you exert in accelerating the resistance, the more force it exerts back on you.

If injury is caused by excessive force, and faster movements result in the body being exposed to greater force peaks (relative the average force, which should be within the safe limits of healthy muscle and connective tissues when typical exercise loads are used), then faster repetitions carry a greater risk of injury.

Additionally, it is easier to maintain proper body positioning and alignment and to move correctly during exercise when using a slower speed of movement, and maintaining proper form reduces the risk of injury by preventing the body from moving into positions where some tissue may be exposed to excessive force due to compression, stretching, etc.

In case this isn’t simple enough, I’ll illustrate with a more concrete example.

Suppose two people, Mr. A and Mr. B, are both stopped in their cars waiting for a red light. When it turns green, Mr. A begins to accelerate gradually, just as Mr. B’s car is rear ended by a truck, causing it to accelerate very rapidly. Who is more likely to be injured?

Is this simple enough, or do I need to reference crash test data, and will you only consider it valid if it was published in the last year?

CPT: NO!! Your physics rationalization is full of assumptions that you know what causes injuries and how to prevent it. Your theory is testable. So test it.

In the meantime, admit that it is just a theory and stop talking like creating a theory proves it.

Real world testable theories deserve real world proof. You have no proof. You have a theory. Stop acting like your theory is proven just because it makes sense in your head.

You have no proof your method is any safer than mine.

Drew Baye: It’s not a theory, it’s a logical deduction based on irrefutable physical laws.

As for proof, how’s this: in over fifteen years of training people for a living, during which time I have trained hundreds of people and instructed tens of thousands of sessions incorporating slow repetition speeds, I have never injured anyone. This includes many elderly people, up into the mid 80’s, people with a variety of physical disabilities, people with a variety of spine and/or joint problems, including one with a grade 3 spondylolysthesis, people with cardiovascular problems, stroke victims with partial paralysis, etc. However, during initial consultations when reviewing medical history and prior exercise experience, many clients have told me how they were injured either working out on their own or with another trainer, usually when performing exercises with a fast speed of movement.

CPT: I see, so it’s so self evident it’s axiomatic, eh? Don’t think so. I’m sure I would have heard of Drew’s Axiom of Exercise Injuries or Drew’s Law of Exercise Injuries if it existed. Even if something appears self evident, it still must be tested.

No Drew. What you have here is definitely a theory. And theories must be put to rigorous proof before they can be accepted as laws.

(Referring to my comment about never injuring clients with slow reps) I’d like to believe that, but it’s purely anecdotal. As proof, it’s worthless. If you want to write it up as a series of case reports, then it might entice some researcher to put your theory to the test.

(Referring to my comment about clients telling me about being injured exercising with fast movement speeds) There you go again blaming injuries on fast speed of movement. The challenge here is that you appear to have started from a premise of fast speed of movement causing injuries, then went looking for it. This is a backwards way to attempt to do science.

I’ll leave you with the words of Claude Bernard in the hopes that they will help you refine your method:

“Men who have excessive faith in their theories or ideas are not only ill prepared for making discoveries; they also make very poor observations. Of necessity, they observe with a preconceived idea, and when they devise an experiment, they can see, in its results, only a confirmation of their theory. In this way they distort observation and often neglect very important facts because they do not further their aim. . . . But it happens further quite naturally that men who believe too firmly in their theories, do not believe enough in the theories of others. So the dominant idea of these despisers of their fellows is to find others theories faulty and to try to contradict them. The difficulty, for science, is still the same.”

CLAUDE BERNARD, An Introduction to the Study of Experimental Medicine, 1865

Drew Baye: They’re not my laws, they’re Newton’s. I’m just pointing out an obvious consequence of them.

CPT: So you think you can say Law A + Law B + Observation C = Theory of Exercise D and the issue is settled? Sorry, it doesn’t work that way.

There can be other vitally important observations that you’ve missed, other chemical interactions, neurological messages, tissue repair functions, shear forces you’re unaware of, etc., etc., etc. That’s why it’s a theory. A perfectly splendid little theory that might be gloriously right or fatally flawed. We won’t know till it’s tested.

So till Mannie or Westcott or one of your other HIT cheerleaders publishes a paper PROVING that sensible HIT training is vastly safer than other forms of training… STOP MAKING AN UNSUPPORTED SAFETY CLAIM ON THEORY ALONE!! That is NOT how science works. Exercise science may be thought up in armchairs, but it must be proven out in the real world on real humans with real experiments.

There is a saying, Publish Or Perish. You must Publish verifiable results in peer reviewed journals that support your theory, or surely it will Perish for lack of support. If you wish HIT to be respected as a scientific training system, you must prove it scientifically. Making unsupported claims of safety for decades without ever attempting to prove them is why HIT is not better respected.

Do you have a safer method? Don’t just tell me, SHOW ME!!

Drew Baye: How about we approach this from a different direction?

Suppose we set out to design an activity for the purpose of causing injury to participants. Knowing that injury is caused when a tissue is exposed to excessive force (either trauma or fatigue failure caused by accumulation of small amounts of damage over time), we would then look for a way to increase the force the body is exposed to as much as possible, as well as the different ways force can cause injury (compression, strain, shear, etc.).

There are many activities we could come up with (frighteningly, many would resemble popular fitness fads), but most of them would have one thing in common. If our goal was to expose the body to as much force as possible, we would want the activity to involve rapid acceleration (quick increases in speed or change in direction), with quick yanking, jerking, bouncing, etc. If acceleration is great enough, the forces the body is exposed to can be several times higher than the weight of the moving mass, enough to cause an injury. The mass could not be too heavy, or it could not be moved quickly, but it would have to be heavy enough that the product of the mass and the rapid acceleration would result in enough force to injure the participant. A moderately heavy (relative to the users strength) barbell would be a perfect tool for this. The resulting activity would involve quick movements with a barbell.

If rapid acceleration were not an option for some reason, then we would have to increase the other function of force, mass. However, since the amount of force healthy muscles and associated connective tissues can withstand is greater than what they can contract against concentrically, the weights would have to be far, far heavier than normal exercise loads. More than 150% of a person’s 1RM (people’s eccentric strength is between 20 and 50% of their concentric, and the limit would have to exceed the eccentric strength significantly. Without the ability to rapidly accelerate to cause an injury, if we wanted to harm the participant we would just have to suspend weights from them which were far, far heavier than they could lift during exercise. Typical exercise loads (70 to 80% of 1RM) would not be heavy enough to cause damage to healthy muscles and associated structures when moved in a controlled manner, in proper form (avoiding potentially harmful moment arms).

Drew Baye: (Responding to CPT getting worked up about being accused of malpractice) Regarding malpractice, re-read what I said:

“In my opinion, recommending fast movements during exercise to the elderly is malpractice.”

(Update: this absolutely is malpractice and I should not have stated it as an opinion.)

I would consider any exercise movement to be too fast if a person can not stop instantly at any point during the movement and hold the weight motionless, if the resistance encountered increases more than a few percent as a result of acceleration, or if the individual is unable to maintain proper positioning (excessive body sway, obvious yanking or heaving, etc.).

I find that by my standards most people’s form starts to deteriorate when they start moving faster than 5/5 over a typical range of motion.

Drew Baye: An experiment some might be interested in trying that will demonstrate some of what I’ve written about earlier:

If you have a barbell and a spring scale, load the barbell with a weight that is only moderately difficult for you to curl, and step on the scale. Note the weight.

Slowly curl the barbell one time – start as slowly as possible then take 5 seconds or longer to both lift and lower the weight. As you do, watch the scale. You should see very little variation in the weight it reads, an indication of the reactionary force of the barbell as you accelerate during the exercise.

Curl the barbell again, this time faster, about 2/2. Note the increased variation on the scale.

Now, if you curl the barbell one last time, even faster, about a 1/1. Even if you attempt to reverse direction in a controlled manner, you’re going to notice much more variation on the scale.

If you don’t mind risking your body for science, you could try another rep, this time moving as fast as possible, however I don’t recommend it. By this point it should be clear how much of a difference speed of movement (specifically acceleration) makes in the force the body encounters during exercise.

CPT: I think Drew is incredibly resistant to hearing any information that does not conform to his prejudices in regards to weight training. I answered Drew’s concerns about lifting speed back around the posts in the #30’s:

Olympic Weightlifting is the most explosive sport in the world. By Drew’s logic, it should have the highest injury rate in the world. It does not. Olympic Weightlifting is one of the safest sports to engage in with extremely low injury rates per hours participated.

Relative Safety of Weightlifting and Weight Training
Brian P. Hamill
Strength and CondoRes. 8(1):53-57.1994
Injuries per hundred hours of participation
At the top of the list, soccer.
Soccer – 6.2
Way down at the bottom of the list is Olympic weightlifting.
Weightlifting – 0.0017

Drew Baye Wrote: “I would strongly caution the elderly not to work with any trainer recommending a fast speed of movement during exercise.”

I would strongly caution the elderly not to work with any trainer who doesn’t keep up with the latest research:

Scandinavian Journal of Medicine & Science in Sports:Volume 18(6)December 2008p 773-782
Explosive heavy-resistance training in old and very old adults: changes in rapid muscle force, strength and power
P Caserotti, et al

These findings demonstrate that explosive-type heavy-resistance training seems to be safe and well tolerated in healthy women even in the eighth decade of life and elicits adaptive neuromuscular changes in selected physiological variables that are commonly associated with the risk of falls and disability in aged individuals.

Drew Baye Wrote: “…the scientific literature for slower, controlled speeds is anything but weak. See

Carpinelli RN, Otto RM, Winett RA. A Critical Analysis of the ACSM Position Stand on Resistance Training: Insufficient Evidence to Support Recommended Training Protocols. Journal of Exercise Physiology Online 2004;7(3):1-60″

I did. Strange that Drew referenced it since Carpinelli refutes both Super Slow repetition durations and extended Time Under Load manipulations of set length. The science Drew cites, specifically refutes his position:

No study using conventional exercise equipment reports any significant difference in muscular hypertrophy, power, or endurance as a result of manipulating repetition duration.

There is very little evidence to suggest that a specific time-under-load (e.g., 30s versus 90s) significantly impacts the increase in muscular strength, hypertrophy, power, or endurance.

So Carpinelli, who Drew cites to “support” his position, specifically says he’s wasting his time bothering with long repetitions and set lengths.

Drew Baye Wrote: “Research does not show any benefit to “high speed” or “power” training…”

Power training is more effective than strength training for maintaining bone mineral density in postmenopausal women
Stengel, et al 2005, (2 year followup in 2007 confirmed the trend)

Whereas the Power Training group maintained Bone Mineral Density at the spine and the total hip, the Strength Training group lost significantly at both sites.

During the resistance training, the Strength Training group used slow and the Power Training group fast movements; otherwise there were no training differences.

Drew Baye Wrote: “In my opinion, recommending fast movements during exercise to the elderly is malpractice.”

One should not carelessly toss around accusations of malpractice when they train their clients using slow repetition speeds that can contribute to osteoporosis.

I challenged Drew way back at Post #43 to post studies that confirm his claims of a safety advantage for slow repetition speeds. He claims that these speeds are safer, yet he has only opinions and theories to back up his claim. I posted studies showing a lack of increased danger from activities that include fast repetition speeds. There are many, many more of the same, most of them published recently with excellent methodology and peer review.

I think I’ve said all that needs saying on this subject.
Drew’s claims of safety are not scientifically confirmed.
Drew’s claims that others methods are dangerous are not scientifically confirmed.

Talk with him more if you wish, but I’m finished. I don’t enjoy talking to people who stubbornly hold to a cherished theory no matter how much scientific evidence is shown them.

I sincerely hope that HIT practitioners get good results with their clients. I know that I get good results with mine. I see no reason for the animosity that HIT practitioners show towards other styles of training. It is certainly not based on reliable scientific studies.

In parting, if anybody ever tells you that their style of training is incredibly safe, unlike the other more dangerous methods out there… Ask them,”Really? That’s interesting. Can you show me some peer reviewed studies on that?”

Drew Baye: First off, please read what I wrote before about survivorship bias – this would explain the lower injury rates for Olympic lifting, as well as for many more dangerous sports – this does not make them appropriate for the majority of people.

As for speed and injury, I’ve provided proof over, and over, and over. There is a very simple relationship between force and injury, and between acceleration and force. The greater the acceleration the greater the possibility of injury. I don’t know how much simpler I’ll be able to make it for you.

CPT: One should not carelessly toss around accusations of malpractice when they train their clients using slow repetition speeds that can contribute to osteoporosis.

Drew Baye: There is nothing about slow repetitions that would contribute to osteoporosis. Every person I have trained who has had osteoporosis or osteopenia has significantly improved their bone density and this has been the experience of every other trainer I know using slow reps.

CPT: Talk with him more if you wish, but I’m finished. I don’t enjoy talking to people who stubbornly hold to a cherished theory no matter how much scientific evidence is shown them.

Drew Baye: What scientific evidence? The same flawed studies over and over? Anecdotes and surveys which fail to account for survivorship bias?

CPT: I sincerely hope that HIT practitioners get good results with their clients. I know that I get good results with mine. I see no reason for the animosity that HIT practitioners show towards other styles of training. It is certainly not based on reliable scientific studies.

Drew Baye: On the contrary, check the references in

Smith D, Bruce-Low, S. Strength Training Methods and The Work of Arthur Jones. Journal of Exercise Physiology Online 2004;7(6): 52-68

and

Carpinelli RN, Otto RM, Winett RA. A Critical Analysis of the ACSM Position Stand on Resistance Training: Insufficient Evidence to Support Recommended Training Protocols. Journal of Exercise Physiology Online 2004;7(3):1-60

Both show the majority of research supports high intensity training. Also, if you actually read Body by Science you’ll find it is very well referenced and does an excellent job of explaining the science behind high intensity strength training.

CPT: In parting, if anybody ever tells you that their style of training is incredibly safe, unlike the other more dangerous methods out there… Ask them,”Really? That’s interesting. Can you show me some peer reviewed studies on that?”

Drew Baye: Would you also ask someone for a peer reviewed study if they told you jumping off a cliff would be a bad idea? You keep asking for peer reviewed studies, but have failed to dispute the very simple physics involved. Risk of injury increases with force. Force increases with acceleration. The faster you go, the higher the force you encounter, the greater the likelihood of injury.

Also, you have ignored what was discussed about tension and stimulus for muscle and bone improvements, and the fact that muscles are capable of contracting with more force concentrically at slower contraction velocities (force/velocity curve – slower concentric contraction velocity equals higher rate of cross-bridge formation equals greater force).

You can increase the force/tension in two ways; increase acceleration or increase mass. Increasing acceleration results in significant and potentially harmful variations in force, relative the amount of force required to hold or move the mass at a constant velocity. Increasing the mass while maintaining a low level of acceleration results in little variation in force, and a more consistent level of tension over the full range of the exercise, and is also easier to quantify and therefore keep within a known safe level (if you can lift it under control it is not heavy enough to damage healthy muscle or tissues if proper form is used).

Drew Baye: Like I mentioned elsewhere where you quote Rippetoe on specificity of speed, this is backwards.

While fast reps improved performance at fast speeds only, slow reps actually improved performance at all speeds:

Hiroaki Kanehisa1 and Mitsumasa Miyashita1
(1) Laboratory for Exercise Physiology and Biomechanics, Faculty of Education, University of Tokyo, Hongo 7-3-1, Bunkyoku, Tokyo, Japan

Summary Twenty-one male volunteers (ages 23 -25 years) were tested pre- and post training for maximal knee extension power at five specific speeds (1.05, 2.09, 3.14, 4.19, and 5.24 rad-s?1) with an isokinetic dynamometer. Subjects were assigned randomly to one of three experimental groups; group S, training at 1.05 rad-s?1 (n=8), group I, training at 3.14 rad-s?1 (n=8) or group F, training at 5.24 rad-s?1 (n=5). Subjects trained the knee extensors by performing 10 maximal voluntary efforts in group S, 30 in group I and 50 in group F six times a week for 8 weeks. Though group S showed significant increases in power at all test speeds, the percent increment decreased with test speed from 24.8% at 1.05 rad-s?1 to 8.6% at 5.24 rad-s?1. Group I showed almost similar increment in power (18.5-22.4 at all test speeds except at 2.09 rad-s?1 (15.4%). On the other hand, group F enhanced power only at faster test speeds (23.9% at 4.19 rad-s?1 and 22.8% at 5.24 rad-s?1).

END

Shortly after this the forum moderator jumped in and shut down the thread over “concerns regarding libelous words”.

Question:

How many calories does a pound of muscle burn? I keep reading in HIT books that it burns 50-100 calories a day, but then I read stuff like this:

“In reality, one pound of muscle burns about seven to 15 calories a day, not 50, explains Dymphna Gallagher, the director of the body composition unit at the New York Obesity Research Center in Manhattan. So, if a person has managed to stick to a program lifting progressively heavier weights for a long enough stretch of time, they may accumulate enough extra muscle to boost their metabolism by about 14 to 30 calories a day — not several hundred, as is often claimed.”

I’m not sure what to believe, as HIT is based on empirical evidence I am curious as to how we reached higher numbers?

Answer:

I believe the more conservative estimate of around 7 to 15 calories per day to maintain a pound of muscle is more accurate, however resistance training studies have shown a much greater increase in metabolic rate per pound of muscle gained (1, 2), which Dr. Wayne Westcott explains as resulting from an increase in protein turnover in all of the muscle mass trained (3, 4). If you are training hard on a regular basis you’re not just adding muscle, you are increasing the protein turnover in all of the muscle being worked which would have an increased metabolic cost beyond the energy demands of the workout. This is where you get numbers like 50, although I believe 50 may still be a bit on the high side.

Like most things, the actual increase in metabolic rate would depend on numerous individual factors. For example, if training increases the calories burned per pound of muscle someone starting out with more is going to have a greater increase in metabolic rate than someone starting with less even if they gain the same amount. In my opinion a more realistic range taking into account both additional muscle mass and increased protein turnover is around an additional 25 to 35 calories per day per pound.

Even by more conservative estimates strength training is still preferable to endurance activities or so-called “cardio” for fat loss for numerous reasons. [continue reading…]

During a recent Facebook conversation with a friend about his workouts another person suggested he try Bikram or “Hot” Yoga, a method performed in rooms heated to over 100 degrees as an alternative to his high intensity training workouts. I replied,

The technology of exercise has advanced tremendously over the past century (mostly thanks to Arthur Jones and Nautilus in the 1970’s) in terms of both methods and equipment. To still be doing a method like yoga that is over 5,000 years old when more advanced and more effective methods are available makes no sense from a purely physical standpoint. Just like it would make no sense for us to send our soldiers into battle with spears and shields instead of modern rifles and body armor.

Some people enjoy doing historical reenactments, though, and if they’re doing it for the enjoyment, that’s great and I’m not going to discourage it, whether it is exercise or warfare.

The same could be said about many other popular exercise trends or the belief that barbells or other types of free weight equipment are superior to Nautilus machines for building general muscular strength and size. The appeal of some of these ancient or “old timey” methods and equipment is often more a matter of the image they evoke or an association with a particular group than with their relative effectiveness.

If your primary concern is the image associated with a particular training method, or the social or recreational aspects of it, then the level of the technology involved is irrelevant. However, if your primary concern is results you should use the most technologically advanced methods and equipment available to you that is appropriate for your goals.

A couple things to consider:

Just because something is newer does not mean it is more technologically advanced. Technology is the practical application of knowledge, and the design of many exercise machines being produced today exhibits far less knowledge of the subject than those being made by Nautilus in the 1970’s.

A Nautilus machine is superior to a barbell in many ways, but a barbell is superior to an improperly designed machine.

It is important to distinguish between older methods and tools that are still being used or have been “rediscovered” because of their relative effectiveness as opposed to tradition or trendiness.

If your specific goals involve the skill of using less technologically advanced tools (barbells in powerlifting and weight lifting, stones in strong man competition, etc.) then those are the most appropriate tools for that aspect of your training. For example, although a Nautilus machine will increase the strength of the muscles involved in the barbell bench press only bench pressing will improve your skill in that specific movement, which makes a large contribution to performance.

Technology has as much to do with how a tool is used as the tool itself. Improper use of a tool can nullify any technological advantage it might provide. Proper training with nothing but heavy stones and other odd objects will produce far superior results to improper training with the most technologically advanced equipment in the world. Proper training and technologically advanced equipment will produce the best possible results.

If you are not redirected within 5 seconds click here.