If your goal is to maximize the potential benefit of an exercise while minimizing the risk of injury, you should move at least slowly enough to be able to do three things:
- Reverse direction smoothly between the positive (lifting) and negative (lowering) phases of the repetition, without yanking, jerking, or bouncing the weight
- Maintain correct body positioning over the full range of the exercise
- Focus on contracting the target muscles
Reverse direction smoothly
To hold a weight motionless or to lift or lower it at a constant velocity you must produce a level of force equal to the pull of gravity on the weight. To start lifting, or to reverse direction between lifting and lowering movements, however, requires a change in velocity, or acceleration, which requires a change in force. You must produce more force to slow to a stop and change direction between the negative and positive (the lower turnaround) and less force to slow to a stop and change direction between the positive and negative (the upper turnaround). The acceleration will be proportional to the force.
If the acceleration is low the force does not vary significantly from the amount required to hold or move the weight at a constant velocity, only a few percent even at typical repetition cadences, and the tension on the target muscles won’t vary significantly other than due to changes in leverage. If you attempt to lift the weight explosively and the acceleration is high, the forces can vary by a huge amount, increasing the force against the muscles to potentially harmful levels then decreasing it proportionally over a portion of the range of motion after positive acceleration stops, increasing the risk of injury while reducing the efficiency of muscular loading.
Reversing direction smoothly, with low acceleration, prevents the force encountered by the muscles from varying too much relative the resistance provided by the weight or machine, which minimizes your risks of injury and keeps the tension on the target muscles more consistent over the full range of the exercise. It is not necessary to move extremely slowly to accomplish this, however.
Mike Mentzer recommended a moderate, 4/4 repetition cadence
If you use a weight that allows you to perform at least a moderate number of repetitions, the average force your muscles are required to produce will be well below their concentric maximum, which is below their eccentric maximum, which is below the amount required to cause an injury (assuming healthy tissue and no pre-existing injuries). For example, if you perform an exercise with a load that is approximately seventy five percent of your one repetition maximum, you already have a margin of safety way over twenty five percent. With this sizeable safety margin a few percent variation in force is not going to significantly increase your risk of injury, and the difference in the variation of force between different repetition cadences is very small as long as the turnarounds are performed smoothly.
This has been demonstrated with force gauge experiments and can be proven mathematically. I’ve discussed this with several friends who are engineers, one of whom shared the following: Assuming a typical range of motion of about half a meter, if you calculate the force required to bring a one hundred kilogram or two hundred and twenty pound barbell to rest over a distance of about four inches at the cadences listed below, you get the following percentage of the load used (gravitational constant rounded up to 10 and results rounded off to the nearest whole number):
1/1 cadence (.5 m/sec): 113%
2/2 cadence (.25 m/sec): 103%
4/4 cadence (.125 m/sec): 101%
10/10 cadence (.05 m/sec): 100%
In other words, as long as the acceleration occurs over a distance of at least a few inches the difference in peak force between a 2/2 repetition and a 10/10 repetition is only a few pounds.
If you double the distance over which acceleration occurs during the 1/1 cadence to eight inches, which is more realistic if you are attempting to reverse direction smoothly at that cadence, the percentage of load required to bring it to rest comes down to only 106%, which would neither be a dangerous level of peak force or significant variation in tension. The faster you go, the more difficult it is to reverse direction this smoothly, however.
It becomes easier to turnaround smoothly as you go more slowly, but moving any more slowly than necessary to do so does not significantly reduce your risk of injury or improve the efficiency of muscular loading. With proper training and practice a three to four second cadence results in a slow enough speed on most exercises for most people to perform reasonably good turnarounds.
Maintain correct body position
Your body positioning affects the levers your muscles work against and the forces encountered. Correct positioning results in the muscles working against levers which provide resistance which is reasonably well balanced to the strength of the muscles over the range of motion and which do not expose the joints to potentially harmful compression or stretching. Incorrect positioning can result in poorly balanced resistance and underload the muscles over significant portions of the range of motion, as well as potentially harmful compression or stretching of joint tissues.
A lot of this depends on the exercise and the equipment being used. It is much easier to maintain correct positioning during certain types of movements and with certain types of equipment than others. However, as a general rule the faster you move the harder it is to maintain correct body position. Up to a point, moving more slowly will make it easier to maintain correct body position, as well as to detect and correct incorrect positioning or movements.
Focus on the target muscles
The goal of an exercise is not to use your muscles to lift the weight, but to use the weight to efficiently load the muscles. It is easier to focus on and feel the tension in the target muscles and to be able to adjust your form based on this feedback when you are moving more slowly. Like turnarounds and positioning, this is easier with slower movement, however it doesn’t require moving extremely slowly.
Downsides of moving too slowly
While I’ve written a lot over the years about the problems with moving too quickly during exercise, I have made little mention of the problems with moving too slowly, mainly because there are only a few and they are minor compared with the problems with moving too quickly.
Two important factors in stimulating muscular strength and size increases are metabolic stress and muscle damage, both of which appear to be reduced as speed decreases.
Reduced metabolic stress
Although metabolic stress and fatigue are more strongly associated with tension than mechanical work, as isometric exercise proves, mechanical work does play a role, and it has been demonstrated that a higher rate of mechanical work produces a faster rate of fatigue, most likely due to affects on several related factors. All else being roughly equal, more repetitions will result in greater muscle damage or microtrauma, which is a contributing factor. Additionally, since the muscles are significantly stronger and use less energy during eccentric contractions, it appears a longer negative may reduce the rate of fatigue, similarly although not to the same degree as rest-pause.
When I began to suspect this in the mid 2000’s I performed an experiment with several clients and invited other trainers to do the same and report the results: Perform as many repetitions of an exercise as possible at a 2/2 cadence, recording the time to concentric failure. Wait thirty minutes and repeat the exercise with the only change being to use a 10/10 cadence, recording the time to concentric failure. I had clients perform this with both upper and lower body exercises (usually leg extension and arm curl, but some times leg press and pulldown) and almost all were capable of continuing the exercise for up to fifty percent longer with the slower speed only thirty minutes after the first set. I repeated this later comparing a 2/2 and 2/10 cadence with similar results. The longer negative appeared to reduce the rate of fatigue with the selected resistance, allowing for a longer time to concentric failure or time under load (TUL).
I repeated these tests only a few years ago with equipment specifically designed for very slow repetitions with the same results; the rate of fatigue is lower with slower repetition speeds. While it could be claimed the additional time is beneficial, what it really means is it takes longer to recruit and fatigue all the motor units in the targeted muscles. It could also be claimed this allows for the use of greater loads than with faster reps for a given TUL (and the force/velocity curve supports this), but then it would make more sense to only perform the negatives for a longer duration rather than both phases (and in a study by Westcott discussed in his book Building Strength & Stamina a 4/10 protocol appeared to be more effective than 10/4). Also, while tension would increase, it might be at the expense of microtrauma. A more moderate repetition speed would probably be a good compromise between high tension and high muscle damage while allowing for more efficient inroad than very slow protocols.
Reduced muscle damage
Most of the muscle damage or microtrauma occurs during eccentric contractions and appears to be related to the volume of mechanical work. The slower the repetition cadence, the fewer repetitions performed within a set amount of time, the less muscle damage is likely to occur, potentially reducing the stimulus for muscular strength and size increases.
Not too fast, not too slow
While any repetition speed can be effective as long as you train hard and progressively, if you want to maximize benefit while minimizing risk, as I wrote above you should move at least slowly enough during exercise to be able to reverse direction smoothly, maintain correct body positioning, and to be able to focus on contracting the target muscles. If you’re not sure about the proper speed you’re better off moving too slowly than too quickly, but moving extremely slowly is not necessary and does not provide any benefits over more moderate speeds in terms of effectiveness or safety.
For the majority of people, a three to four second cadence (three to four second positive phase and three to four second negative phase) results in a good average speed of movement for the majority of exercises, not being too fast on exercises with a longer range of motion or too slow on exercises with a shorter range of motion.
Can you make gains with SuperSlow?
While discussing rep speed on my high intensity training facebook page someone asked me whether it was possible to make long-term gains using SuperSlow protocol, which uses a very slow 10/10 cadence.
Long term gains are possible using any repetition cadence or method if you are doing it hard, progressively, and consistently (assuming you still have further potential for growth and are doing everything else reasonably correctly). Slow reps, fast reps, negative-only, rest-pause, static holds, timed static contractions, etc. Anything done with a high level effort will eventually get you there, some will just get you there faster, more efficiently, and with less risk of injury and less wear and tear on your body.
I know some people who have gotten very strong and muscular using SuperSlow and there are a lot of personal training studios out there using it exclusively with good results. I am not disputing the fact slow reps are effective, but rather the claim they are safer and more effective than more moderate repetition cadences.
HIT trainer Vee Ferguson has built an impressive physique with SuperSlow repetitions
Without getting too far off topic, I think the primary reason some people have reported poorer results with SuperSlow than when using conventional repetition methods is not the slower speed but the very long set durations and significant reduction in load they require.
While research shows relative effort to be more important than load, consider most research is not done with cadences and rep ranges resulting in sets lasting three minutes (the current recommendations for SuperSlow are a TUL of 100 to 180 seconds). Load may not be the most important factor, but it does matter, and when load is too low strength and size gains will suffer regardless of the relative effort.
As an extreme example, imagine if you were to cut your loads to only ten percent of what you normally use. You’d end up doing very long sets, and even if you performed every exercise to momentary muscular failure you’d probably end up with much slower strength and size gains. When using typical rep ranges and loads – from around five to twenty at typical cadences and TULs – effort appears to be key, but if you keep dropping the weight and increasing the time you’re going to hit a point where it starts becoming less effective for strength and size gains.
Anecdotally, I had noticeably better results with SuperSlow when using a much shorter rep range of three to four (under 90 seconds) than when using a rep range of four to eight, and most clients responded better to the shorter rep range as well.
The reason I recommend a more moderate speed and TUL (around six to ten reps at 3/3 to 4/4 as a starting point, adjusting based on individual response) is it seems to be the best compromise of what I consider the most important factors: tension, microtrauma, metabolic stress, safety, ability to maintain focus, learnability, ability to observe, identify and correct discrepancies, etc.
Comments on this entry are closed.
That’s why I follow You. Everything is evidence based yet this does not get in the way of keeping it simple, safe, effective and efficient. I got better results using shorter TUL and 4/4 reps with dumbbells. Also, it shows why other bodyweight approaches aren’t as effective – most trainers don’t treat bodyweight exercise as hypertrophy oriented and their progressions are a joke. I find it sad how their creative dangerous “harder variations” often do very little to positively affect mechanisms behind hypertrophy.
When you factor in the *actual* speeds at which a heavy weight is lifted, isn’t it sorta hard to induce significant accelerations?
The flip side to this is: When lifting lighter weights with rapid turn-around accelerations (lower), doesn’t that sort of “restore” the net force to that of lifting a heavier weight?
Which can in fact be used to some advantage. Think HeavyHands.
I see the real risk is in pliometrics, where these accelerations are really blistering. But, apparently, good for CrossShitters.
What the SuperSlow peeple don’t address (not that I’ve seen) is: If SuperSlow is so good, well, then, Isometrics ought to be Da Bomb! Infinitely Slow!
As always, excellent articles/posts.
Angst,
The heavier the weight the more difficult to lift it rapidly while maintaining strict body positioning and only using the target muscles, but it is possible to drop a heavy weight quickly which you then have to produce a lot of force to stop before reversing direction, and it is possible to use larger muscle groups and extraneous movements to rapidly accelerate a weight that is too heavy for the target muscles. The exaggerated hip and back extension some people perform when curling and the hip and knee extension some people perform when performing lateral raises and overhead presses are examples of this. This is one of the reasons for using at least a moderately slow cadence; it makes these extraneous, unwanted movements more obvious, and easier to detect and correct.
If you attempt to lift a light weight more rapidly to increase force, you end up with a level of force that is significantly different from the weight and between reps and hard to quantify, and that is not consistent over the full range of motion during the positive, and you end up significantly underloading the muscles during the negative.
There is no place for plyometrics in a sensible training program. It does not provide any general physical benefit that proper strength training doesn’t provide more effectively and far more safely.
Drew,
Excellent points.
Do you agree that the “logical conclusion” of super-slow is the isometric?
I don’t use isometrics much, but they may have some value. I’ve used Pete Sisco’s Static Contractions for a while, seemed to have yielded some results. I’ve read good things about old Charle’s Atlas’ Dynamic Tension. Would seem to be esp. useful to people with limited range of motion.
At full lockout, I can more than double, poss. triple my actual lift (1″ movements), as I’m sure most people could.
I at least FEEL accomplished, at that moment! 🙂
Angst,
No, because premise of SuperSlow is not that slower is better, which would ultimately lead to isometrics, but that is necessary to move slowly enough to average a 10/10 cadence (anything from 8 to 12 seconds in each direction is considered acceptable) for efficient muscular loading and to minimize risk of injury.
I do not think isometrics are optimal, but they are an effective substitute when dynamic exercise is not possible due to physical limitations or lack of equipment. Isometric should not be performed at or near lockout on pushing movements, however, due to the small lever and large loads required. You are better off performing them near the mid-range position, where the lever is larger and less weight is required, but you are still a safe distance from start point or stretch.
Drew, I always appreciate your cogent analysis!
Hi Drew,
In one of your videos you have told that your rep range recommendations are between 7-10 and here i read 6-10, which is the one you recommend now a days ?
Hey Zafer,
I currently start people with six to ten reps at a 4/4 cadence. It really doesn’t make that much of a difference though. It’s only meant to be a starting point, an average from which to make adjustments based on individual responses. That’s all any of these numbers are: starting points based on averages meant to be adapted to the individual. Applying the principles correctly is more important than following any specific performance guidelines or programs.
Thankx for the wonderful and logical reply!!!
This average starting 6-10 reps is for upper as well as lower boy right?
Hey Zafer,
With free weights and machines I have people use this as a starting rep range for the whole body. With bodyweight I have people go slightly higher, starting with eight to twelve for the upper body and ten to fifteen for the lower body, trunk, and neck.
Hi drew. May I ask you for your opinion on the kettlebell swing and snatch? Paradigmatic of high force, fast, ballistic moves. I am glad I am asking you and not Arthur Jones.
I am indeed concerned because of the high force nature of these moves BUT I have to say that there is no question that they raise my conditioning to a far higher level that I can achieve with weights, even minimal rest HIT sessions. If I want to get my resting heart rate down to 50, I swing to oxygen debt once a week with a moderate [28kilos] bell-just one set after warm up. I can do the same with a 40kilo but the 28 is more effective for some reason, even though my style is crisp in both. Furthermore, I cannot find any exercise which does not irritate my back except the swing-It makes it positively feel good. Deadlifts, no matter how carefully performed are a no-no and the medx/kieser low back machines don’t feel great either. In the swing, the back is constantly braced so worked quite hard. ABS too at the bottom of the movement.
Thoughts?
Robyn,
I strongly recommend not performing any exercise which requires weights to be swung rather than lifted under strict control. If you are not experiencing a significant metabolic and cardiovascular demand from normal exercises and if they’re bothering your back but swinging does not you’re not performing them correctly. I suggest finding a qualified High Intensity Training instructor in your area and getting a few sessions.
Drew,
Very nice post, one of the best discussions of rep speed that I’ve seen in a long time.
Your engineer friends are correct about the relatively minor impact that momentum has on any gradually initiated concentric. I’ve done similar calculations, and gotten very similar results. You can also find studies where people have estimated accelerative forces from high speed videos of power lifters, and those results suggest that it isn’t that hard to avoid excessive force upon initiation of a lift.
The place where many get into trouble is to focus on the equation F=M*a, which leads to an over emphasis on acceleration. Actually, the force that the user needs to generate is
F=M*a +M*g = M(a+g),
where g is the acceleration of gravity.
If you want to know how important forces from acceleration are, just compare the magnitudes of ‘a’ and ‘g’. In metric terms, gravitational acceleration is 9.8 M/s^2, or 980 cm/s^2. That is a relatively big number, which means if you want to experience significant accelerative forces, you have to be able to accelerate the bar quite rapidly (on a par with 9.8 M/s^2). And that will only happen if the weight is relatively light. But if the weight is relatively light to begin with, you have a large safety margin in terms of the amount of force you can handle.
After reading the studies that had been done on power lifters (bench press), I came to understand that, when it comes to the performance of the concentric, your exposure to momentum is self limited:
– If you are lifting a very heavy weight (90%RM or so), you simply cannot generated enough extra force to accelerate the bar rapidly. A ballistic movement just can’t happen.
– If you are lifting a light weight (50%-60%RM), you can produce enough force to accelerate the bar, and ‘a’ can be significant relative to ‘g’. But since you are only lifting roughly half of what you can handle, you have plenty of margin for safety.
If you think about it, the amount of acceleration that you can produce is always limited by the amount of weight and the maximum force that you can produce by voluntary concentric contraction.
The big danger from accelerative forces is on the eccentric.
Imagine you are locked out on the finish of the bench press. To accelerate the bar downward, you need only unlock your elbows and relax your muscles. The bar will then accelerate downward rapidly, at up to 9.8 M/s^2. The downward acceleration is not limited by your strength, it is limited only on the high side by the force of gravity.
Now if you are benching in a cage and have the safeties set high enough, there is no consequence from just letting the weight drop, other than making a big bang and maybe bending the bar, or the safeties. But if you change your mind at the last minute, or don’t have safeties, then you may be put into a situation where you are eccentrically breaking the fall of the bar, trying to bring a high velocity weight to a dead stop within a short distance. That will generate a very high force, and the deceleration that you have to apply may match or even exceed ‘g’. You are then pushing yourself to the limits of your ability to eccentrically resist force.
So from a safety perspective, the most important thing is to control the descent of the bar so that it does not develop sufficient velocity to create a problem at the bottom.
Craig,
The lower turnaround is potentially the most dangerous part of many exercises for this reason, which is why I caution people not to bounce, yank, or jerk the weights. If you can perform the lower turnaround smoothly you’ve eliminated much of the risk. This is also why I caution people against negative-only or negative-accentuated repetitions unless they have very good form and start with a conservative load and have either good spotters or a mechanical stop when performing any exercise where the weight is above them.
Drew, Great article!! You brought up a lot of good points that I had never even given thought to regarding super slow reps. I had always been under the impression that slower was better.
Drew,
Excellent post. You definitely hit on the head the negative part of extensive negatives. I have utilized many different time combinations and have found 3-4 to be best for me.
I also wonder if the attention to so many objective markers, TUL, Resistance and reps, creates greater focus and thus greater results.
Keep up the good work.
DJM
Hi Drew,
Fantastic post!
I was curious, if the negative is so important, why do we rarely see pro bodybuilders using them . They normally train 1/1 and fatigue the muscle as quickly as possible, but not with so much obsession with load and TUL?
Thank you, Bradley
Bradley,
They are performing negatives, just not slowly.
@ Bradley – It is of course worth noting that MANY bodybuilders also suffer from “busted up weightlifter syndrome” in terms of having various joint and or spinal issues. Quicker tempos can certainly build muscle just fine, but may not be ideal for long-term injury prevention. If your weight training program is not SUSTAINABLE, you got nothing in the long run. Looking “buff” and having healthy joints are not always symomous.
Of course, as Drew has pointed out, very slow reps probably are not ideal either. The truth of any matter usually seems to lie somewhere in the middle of the extremes of opinion.
Hey Drew,
In theory size principle does not support that you will have worse results if you use significant less weight.
Why do you think it is an important factor?
Is it because of the metabolism ( muscles will not be well supplied with oxygen over time)?
Dan,
The size principle deals with motor unit recruitment and explains why high loads aren’t necessary to recruit all the motor units in the targeted muscles. It has nothing to do with the relative effectiveness of training with different levels of tension. You don’t need to have extremely high levels of tension for exercise to be effective, but effectiveness will be reduced if it is too low.
A very good piece Drew. Nicely explains the very significant tension differential. i.e when I complete say a set of pull downs with a resistance that allows an 8 – 8 cadence for circa 9 reps to failure I get no DOMS or really worked feeling. and an 8 second eccentric definitely feels like a relative unload / rest Conversley a set of 3 / 3 chins, 5 reps, s/h at point of concentric failure and my upper body tells me about it for days.
Great article Drew, Trying to get the message across to students that swinging, throwing, bouncing, and yanking weights does not make you faster and more powerful but they keep bringing up the F=ma formula. How would you explain it? I personally don’t think the formula of mechanical engineering can be applied to muscular physiology.
Keep up the good work
Christian
Christian,
Speed and power are dependent on strength, not separate qualities, and strength can be improved with any repetition speed. You’re just less likely to injure yourself or develop joint problems later in life if you avoid moving too quickly during exercise.
Hi,
If i cut the load, why do i end up which much slower strength and size gains?
Even with the lightest weight, the intensity could be very high.
Why is the length of a set a limiting factor?
Dan,
Because tension is an important factor in stimulating muscular strength and size increases. While a variety of repetition ranges and loads appear to be effective, below some point the load will not be enough to create sufficient tension in the muscle, which also negatively effects the rate of fatigue and degree of muscle damage. Length is a factor because, all else being equal, how long you are capable of performing an exercise is inversely proportional to the load used.
Intensity of effort appears to be key, but tension definitely plays an important factor. I can not discuss the details yet, but a study which is currently under review showed exercise performed to momentary muscular failure improves muscular strength and size more than rest-pause using a heavier load stopped short of momentary muscular failure, but rest-pause improves muscular strength and size more than continuous reps when both are stopped short of failure. This suggests relative effort is more important than load, but if all else is equal, a heavier load is more effective.
Great post Drew.
You seem to have come to similar conclusions as me on this issue. I’ve experimented extensively with very slow reps in lower TUT ranges (I knew right off the bat that 2 minute TUT’s were not a good way to go) in my own workouts, and with clients. Like you, I also found, initially to my surprise, that very slow reps “hurt” and “burned” real bad…but actually made the set EASIER in terms of being able to handle x-amount of load for LONGER times than “smooth and controlled” speeds.
The longer TUT’s on higher friction equipment are especially problematic, as the friction gives you a REST during that slow an eccentric. Of course, as you commented, low friction equipment (such as Medx) makes this less of an issue…but still an issue.
So I’ve more or less come full circle on this issue. I now simply use “smooth and controlled” reps with all clients in somewhat higher rep ranges as my “sustainable training” method.
Though I do occasionally get a guy (It’s always men) who simply will not stop jerking and tugging – no matter how much I chastise them for it – unless I make them do very slow reps.
But that’s rare. Most do just fine with smooth and controlled, and selecting exercises which are congruent with human biomechanics. (Bill Desimone has had a big influence on my thinking in regards to congruent exercises.)
Not to get off topic…but I’m curious what your thoughts are on exercise variety for clients, in terms of keeping them “interested” in working out?
I feel “variety” is hugely overrated in terms of RESULTS…but that perhaps it can be good for preventing clients getting bored. Though part of me also feels that proper exercise should not be about “entertainment” anyway. And of course, there are many “minimalist” superslow and HIT studios that do well with client retention rates without resorting to variety for variety’s sake.
Anyway…curious if you find a “minimalist” and simple “circuit” can be a good long-term business strategy in terms of client retention rates?
Actually, it looks as if you already addressed your thoughts on “variety” of exercise here and here.
https://baye.com/the-ultimate-routine
https://baye.com/qa-changing-protocols
But I’m still curious, as someone who has trained in a variety of “minimalist” studios, if you find client retention rates are good that way? I look at some “super slow” type studios that do literally the same 5 or 6 machines over and over…and I’m amazed that clients don’t quit out of boredom?
I’m guessing the key is to really educate new clients about what proper exercise is and isn’t. That it’s NOT “recreation” at all. Set their expectations at the beginning.
Jeff,
Such minimalist routines can be effective, but they are not optimal, especially for bodybuilding purposes. Like I mention in the articles you linked to, there is a place for variation, but it should be based on consideration of the individual’s goals and response to exercise, and not arbitrary (variation for variation’s sake).
Jeff,
Some clients do well on a minimalist circuit, although I like to vary people’s workouts a little over time based on needs and goals and because some variety is necessary to more effectively train some muscle groups. In addition to the other articles on the site I discuss this in the upcoming second edition of High Intensity Workouts.
According to this research, Fast Eccentrics are superior for Hypertrophy. As long as you are in control of the rep, it seems to be a effective way to gain size. I have been using both slow and fast, but the load has to be real heavy for the slow or it seems to easy.
http://www.sweatpit.com/forum/studies/general.adaptation/Phase%20Differential/Farting.pdf
Steven,
Even if more studies confirmed this it would still be a bad idea to perform fast negatives because of the greater risk of injury when doing this with weights.
Drew,
You wrote:
“I repeated this later comparing a 2/10 and 10/10 cadence with similar results. The longer negative appeared to reduce the rate of fatigue with the selected resistance, allowing for a longer time to concentric failure or time under load (TUL).”
I don’t understand this argument, there is no longer negative when comparing 2/10 and 10/10?!
“It could also be claimed this allows for the use of greater loads than with faster reps for a given TUL (and the force/velocity curve supports this), but then it would make more sense to only perform the negatives for a longer duration rather than both phases (and a study by Westcott discussed in his book Building Strength & Stamina showed a 4/10 protocol to be more effective than 10/4).”
Why is a 4/10 protocol more effective than a 10/4, when a longer negative allows for some recovery and therefore has a reduced rate of fatigue?
Thanks Andy
Andy,
That was a typo which I corrected. It now reads, “…comparing a 2/2 and 2/10 cadence…” which should make sense.
I suspect the 4/10 protocol appeared to produce better results than the 10/4 protocol because it allowed a greater increase in load. In the study Westcott also reported better results with both 10/4 and 4/10 than with standard 2/4 reps, breakdowns (drop sets) and assisted reps (forced reps). However, this was performed with individuals who had previously plateaued at 2/4. I discussed the details of this study with Westcott along with the experiments I mentioned a few years ago and we both suspected the real reason the slow positive and slow negative groups appeared to have better strength increases is the reduction in mechanical work and the longer negative allowed for them to increase the weights they used more quickly. It isn’t that they had better strength increases, but rather the protocol allowed for more of an increase in weight. Had the strength testing been isometric the results may have been much different.
Thank you Drew… that makes it clear!
Andy
Hi Drew
I like this article, it has balance and allows the reader to find a range that suits the equipment they have access to, matches the goal and discover effective loading to suit. You tend to write without bias.
As you know 10/10 has a very practical and measurable baseline with which an instructor can track progress of a client, especially in the learning stages. I started at Kieser on MedX at 4/4, I learned RenEx 10/10, what I now find is RenEx equipment can accommodate the skill required to perform the protocol strictly, the machines I use through my own experimentation and understanding of the machine movement arm behavior is that depending on the exercise performed & stroke distance ie CP or LP I tend to vary between 6/6-8/8 this includes the lower turn, also on rotary and pulling movements 3rd rep onwards I perform a squeeze, again I am undecided if this technique is an effective tool on equipment other than RenEx or SSS cam.
Thanks
Pete
Pete,
It helps to have people move more slowly when learning an exercise, but once they have reasonably good form they only need to move slowly enough to maintain proper position, move correctly, reverse direction smoothly, and focus on the the muscles they’re working. SuperSlow/RenEx protocol can be performed with any equipment with reasonably low friction and reasonably congruent resistance curves, and a hold or squeeze can be performed on any pulling or simple exercise when using equipment that provides resistance at the end point.
Drew,
You suggest a 4/4 rep cadence.
Am I right in saying the time for executing a smooth lower and upper turnaround is Not included in your 4/4 suggestion? So the total time for an execution of one rep is in the 12 to 14 seconds range?
Andy
Hey Andy,
No. A 4/4 cadence means the entire duration of both the positive and negative phases of the repetition equals four seconds, including turnaround time.
When Elements of Form is out later in the summer I will release a companion video demonstrating a lot of the things covered in the book.
Hi Drew, I’ve been following your site along with body by science for a few years now. Since then, I started working out and trying to follow the bbs method, (once a week or so, 12-14 minute workout working 5 main body parts at a TUL of around 90 seconds). My cadence is probably a bit longer than you recommend. I haven’t actually timed it but it’s probably 6-8 sec range, pos and neg.
It’s been a pretty good workout for me (beats the heck out of going to the gym several times a week), but I have noticed that I don’t make much gains in strength.
In reading your article, you recommend a faster 4/4 cadence, which just to be sure, I take to mean 4 seconds to extend the weight positively and 4 seconds negative at 6-10 reps. That works out to be a TUL of 48-80 seconds (approx). Personally, I’ve never focused on the reps, but more the TUL, trying to keep it as close to 90 secs as I can by increasing/decreasing weight.
Just wanted to make sure I understood everything before I gave it a try. Ever since I discovered you and bbs, the typical person at the gym now drives me crazy, spending 5+ mins on a machine with 2-3 min breaks between sets! I’m so tempted to tell them how they’re wasting their time, not to mention needlessly hogging a machine! Thanks again for all your great insight!
Ray,
You’re welcome, and yes, you understood correctly. On pushing exercises I recommend a 4/4 cadence and on pulling and rotary exercises where there is resistance in the finished position I recommend holding for a few seconds at the top, using a 4/2/4 cadence. On pushing exercises you should perform 6 to 10 reps and on pulling exercises you should reduce the reps to 5 to 8, since the reps are slightly longer.
Great article Drew, explained a lot about the importance of lowering the weights at slow speed. Thank you for sharing your ideas with us.
Another very basic and obvious point is “elimination of momentum” when a slower rep speed is used during positive moment.
Since momentum = mass x velocity , the more speed with which weight is moved , more will be the momentum.
This means that if positive movement is done with high speed, the weight is gaining momentum and moving itself in a sense and reaches from point A to point B without any quality contraction in the target muscles.
Using a slower rep speed will result in elimination of this momentum to a greater degree so that the weight is “moved” using the muscular contraction and not by the gained momentum due to high speed.
And this is where no swinging, jerking or bouncing of weight is applied , to eliminate the momentum as much as possible.
Drew , I think u will agree with this point.
Bhanu,
Technically, if you are moving you have momentum; the only way to reduce momentum to zero is to perform isometrics. The real issue isn’t momentum (mass times velocity) but kinetic energy (0.5 times mass times the square of velocity). The faster you accelerate the mass the more kinetic energy you give it, and this kinetic energy then reduces the force required to continue lifting it for a short distance after you stop accelerating. So, instead of a relatively consistent application of force and resulting tension, if you try to lift quickly force goes way up briefly, then way down briefly, then averages out.
Hi,
Thanks for your post. I have started training with a 2/4 cadence, following the advice you give in the first edition of High Intensity Training I purchased recently. Previoulsy I had worked using a 5/2/5 cadence. Have your views changed since the first edition came out, and you find that 4/4 is better? Thanks again for the great website, and I love High Intensity Workouts
D.
D,
This article covers my current views on this. There isn’t much more I would add to it.
Hi Drew,
I’ve been training/experimenting for a year now with isometrics(TSC and Max Contraction) because of a chronic inflammatory condition and free access to bad equipment at the small college I work at. I haven’t noticed much difference in strength or size and I’m very frustrated. I love the feeling of this type of exercise during and immediately after working out, but still can aggravate the pain later on and sometimes during exercise. I perform once a week a full-body routine with a perceived TUL in the range of 100-190 sec.
Much of the time I don’t feel that good and I’ll go for a workout and feel better. Your newest post you mention hormone levels. We are the same age and I wonder if I have lower levels, especially with chronic pain that’s been ongoing for many years since an injury from a minor car accident.
Also I still can’t get away from weekly chiropractic for many years. It is a dream of mine to someday get trained by you and/or others within the HIT community.
John,
If you’re not at least gradually increasing your muscular strength and size despite intense, progressive, consistent training and you have your diet, sleep, and related factors sorted out you might have a hormonal problem. I suggest talking with your doctor about it.
I would also recommend increasing your frequency and reducing your TUL to around the 60 to 90 second range.
Great article! As usual, Many of my findings mimic what you discussed. The years I was a staunch Super Slow advocate, early 90’s, I found 4 reps was a nice average…which goes hand in hand wth my fast-twitch muscle blessing.
A 2/4 rep tempo has faithfully served me well since 1978, so I have come to consider any and all “artificial rep tempos” not necessary. While I appreciate their worth for those who struggle to master certain moves…as they build their neurological efficiency.
Based on my own experience, observations, and numerical intuition I have arrived at an empirical rule of thumb for time under load that I call the “square root hypothesis:”
The muscular “micro-trauma” or “fiber fatigue” induced by one set of reps of an exercise is proportional to the square root of the time under tension for that set assuming the tension is constant throughout the set and the set is continued to near failure.
If this hypothesis is true, a single set lasting 144 seconds (2.4 minutes) has only twice the “fatigue value” of a set lasting for 36 seconds, as long as both sets are done to the same degree of failure or near failure (i.e. to the same “rate of perceived exertion”) by the same person.
Under this hypothesis the following workouts are roughly equivalent:
One set to failure of 144 seconds
Two sets to failure of 36 seconds each.
Three sets to failure of 16 seconds each.
Four sets to failure of 9 seconds each.
According to this theory the number of reps is not directly relevant. If you change the number of reps, you will have to adjust the tension to get the same time to failure or near failure.
If you like spontaneous workouts, pick a reasonable weight and do reps to near failure. Record the under load and label it T1. If the square root of this number is less than 12, pick another weight and (possibly) another repetition speed (as long as it is slow enough to be safe) and do another set to failure and record the time T2. If the square root of T1 plus the square root of T2 is at least twelve, go on to some other exercise, otherwise continue until the sum of the square roots of the TUL’s is at least 12.
If this empirical rule is approximately true, it should largely replace current methods of comparing the potential effectiveness of so many sets of so many reps at such and such a cadence at such and such a percentage of the 1RM.
Anybody interested is experimenting with it?
Here’s another application: The Tabata protocol suggests a workout of eight sets (or intervals) of 20 seconds each. If each set (or interval) is done to near failure this results in a “micro trauma” score of 8 time the square root of twenty, which rounds to 36, or three times the fatigue effect achieved by the guy who does one interval to failure of 2.4 minutes (assuming a constant load and cadence for each set of squats and a constant speed and incline for each interval of sprinting). No wonder this grueling protocol has proven so effective in comparison to other protocols involving fewer, but longer intervals at less intensity.
Note that Tabata restricts recovery to ten seconds between sets. If you follow this suggestion you will have to reduce the speed (or incline) of each successive sprint interval (or the load of each successive set of squats) if you want to complete each twenty second interval (or set).
A calculator or table of square roots can come in handy. For starters here are some TUL square roots that result in integer or half-integer values:
4 sec –> 2 fatigue units
6 sec –> 2.5 fatigue units
9 sec –> 3 fatigue units
12 sec –> 3.5 fatigue units
16 sec –> 4 fatigue units
20 sec –> 4.5 fatigue units
25 sec –> 5 fatigue units
30 sec –> 5.5 fatigue units
36 sec –> 6 fatigue units
42 sec –> 6.5 fatigue units
49 sec –> 7 fatigue units
56 sec –> 7.5 fatigue units
64 sec –> 8 fatigue units
If your TUL for a set comes out between two of these tabulated times, for example 51 seconds, just go with the nearest tabulated time (in this case 49 secs which is closer to 51secs than 56secs) for a fatigue value of 7units.
Enjoy!
Hey Forest,
Observation seems to support this, and increases in load or efficiency of muscular loading (resulting in reduced time) appear to impact fatigue more than exercise duration. However, research also shows very little difference in long term effectiveness between different set and repetition protocols, so for the sake of simplicity and ease of progress evaluation I still recommend performing only one, slightly longer set to momentary muscular failure, rather than several shorter ones resulting in an equal cumulative TUL.
Drew,
I’m experimenting with one four-minute AMRAP set, where each rep is done with a 5/5 cadence, and the resistance is chosen so that I can barely complete four of these ten second reps with no pause.
So the first four reps take up the first 40 seconds of the four minutes, and each succesive rep is preceded by barely enough rest to build up enough energy for another ten second rep.
The whole thing takes four minutes, the same time as the Tabata protocol.
What do you think?
Thanks,
Forest
Hey Forest,
I wrote about this in Thoughts on Isochronal Progression and recommend a much shorter set duration.
Drew, is there any truth to the claim that high repetitions or perhaps in this instance TUL, allows for greater potential for fat burning?
Hey Bryan,
No matter what kind of exercise you do or how you do it you’re not going to burn enough calories for it to be worth worrying about. The role of diet is to create a calorie deficit, the role of exercise is to maintain or increase lean body mass while fat is lost.
Great commentary. After years of lifting with a 1-2 second cadence my progress and joints have plateaued. I started the slower 4 second cadence with a lighter weight and love the extra effort it takes to control the weight. How important is it to go to failure? Are more sets necessarily better?
Training to momentary muscle failure is more effective than terminating exercises after an arbitrary number of repetitions or seconds. In most cases one properly performed set of an exercise is enough. More sets are usually a waste of time at best and often counterproductive.