Response to Questions About Mechanical Work and Repetition Speed

I received several e-mails with questions about and requests to repost the following response I wrote to a question in the comments on My Philosophy of Exercise.  If you find anything I write on this web site helpful I encourage you to share it and appreciate you doing so, but please link back to the original, and limit copying and pasting to brief quotes. By having people read and comment on things I write here at Drew Baye’s High Intensity Training rather than on other sites or forums I am able to respond to everything in one place for the benefit of my other readers, and provide additional information or thoughts on the original post or comments.

My response, to a question about mechanical work and repetition speed:

“The most important thing to keep in mind is the key appears to be relative effort, and not load. A wide range of loads and repetition ranges have been shown to be equally effective for strength and size increases in the long run, provided they are used with a high level of effort. With this in mind, the ideal approach would be to use the lowest load required to get the job done. Rather than focus on how much weight you can lift, you should focus on how intensely you are able to get your muscles to contract with a given weight, how efficiently you can use that weight to fatigue the muscles, and only increase it when you are unable to achieve failure within a reasonable time frame.

Rather than trying to lift the heaviest weight you are capable of, you should be lifting the least weight required to effectively load the muscles and thoroughly inroad them within a reasonable time. While it may seem counterintuitive, the better you are at an exercise the sooner you will fail with a given weight.

Don’t mistake being better at exercise for being better at lifting weights or being stronger. Beingbetter at exercise means being more skilled at using the weight to challenge the muscles, to make the movement harder. Being better at lifting weights means being more skilled at creating favorable leverages and using momentum to make it easier for your muscles to move the weight. Being stronger means being able to produce more force, not being able to lift more weight, because the manner in which you lift it makes a huge difference in how much force is required.

If you want to impress ignorant people in the gym, learn to lift weights in the easiest manner possible so you can load lots of plates on the bar and make all sorts of noise.

If you want to become as strong as possible, learn to use the weight to make the exercise as hard as possible to create a stronger stimulus for growth.”

Responses to email questions:

Weight vs. lever

A few people asked how this is possible with the same weight. It is because weight is only one of several factors affecting the resistance the muscles encounter during exercise, the force they must overcome to lift, hold, or lower the weight under control. Leverage, which is affected by body positioning and alignment and range of motion, is a major factor. Acceleration and velocity are major factors. The ability to focus on intensely contracting the target muscles is a major factor. Depending on the exercise and equipment used there are many more. Depending on how you use it, a given weight can be harder or easier to lift, as well as safer or more dangerous.

For example, consider the effect of leverage during a leg press or squat. Despite the weight pinned on the stack or loaded on the barbell being the same over the entire range of motion, the lower half of the range of motion of a leg press or squat is harder than the top half due to the differences in leverage. If you don’t believe me, try a few reps in only the bottom half of the range of motion, then try a few in the top half, keeping everything else (speed, turnarounds, etc.) as equal as possible. The bottom half is more difficult because the longer levers (moment arms) result in more resistance. Weight x lever = resistance (torque, actually).

The goal of proper form is to use the weight to create a a level and variation in resistance that is both maximally challenging to the muscles being targeted and minimally harmful.

How much weight

Enough that you are able to recruit all the motor units in the targeted muscles and achieve momentary muscular failure within about  90 seconds, or around 6 to 10 reps at a moderately slow speed.

If the weight is too light you’ll keep recycling the more fatigue resistant fibers and not recruit and effectively stimulate the larger, high-threshold motor units. If the weight is too heavy form tends to fall apart and injury becomes more likely, especially when approaching momentary muscular failure.

Speed and weight

Moving more slowly in and of itself does not reduce the weight you can use. Your muscles are actually capable of contracting with more force at slower velocities (do not confuse the velocity/force curve with the acceleration formula – they are two different things). Moving more slowly makes exercise harder because it allows you to better control body position and movement and levers and keep the tension on the targeted muscles, as well as improves your ability to focus on intensely contracting them.

Criticisms of rest-pause, negative-only, and “advanced” training techniques

This resulted in more email than anything else. There are numerous problems with each of these, all of which are discussed in Elements of Form,  and I’m not going to repeat all of it here, but the main issues are the misguided focus on mechanical work (total weight or reps) rather than intensity of effort and various safety problems inherent in repeated loading and unloading and intra or interpersonal resistance transfer compounded by progressive fatigue.

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  • MikeG Jan 30, 2012 @ 17:04

    You said “”If the weight is too heavy form tends to fall apart and injury becomes more likely, especially when approaching momentary muscular failure.”” IS this the only reason why its not ideal? if you could avoid injury regardless of weight ( medX Bench press etc) would a 1 rep max workout be usefull??

    I have done some heavy one rep max work, with deadlifts with a trap bar, head great form, never hurt mysefl etc. but I noticed that higher reps work better for adding mass. WHY ? why doesnt lifting as much as possible ( in a vaccuum at least) produce the same results?

    • Drew Baye Jan 30, 2012 @ 17:57

      Mike,

      Injury can occur due to all sorts of reasons other than dropping a weight on yourself, most related to either excessive acceleration or improper path or range of movement resulting in excessive compression or stretching of tissues, or a combination of the two.

      There is no reason to ever perform one rep maximum training and plenty not to, unless you are a competitive lifter.

      A more moderate repetition range or set duration may be more effective because growth stimulation is multifactoral and the contribution of inroad/metabolic stress would be greater.

  • Thomas Jan 30, 2012 @ 18:57

    Hi Drew,

    I feel I get far better inroad and higher tension when I push the weight as hard as I can after dong a slow turn-around. To make it safer, I deliberately try and do my first 4-6 reps slowly, to get some fatigue going. When I begin the harder, “faster” effort, it doesn’t actually go fast, but I am trying to make it go fast. I make sure I don’t use any body english when doing this. When I do this kind of set, I fail sooner than if I am doing purely slow reps. My assumption is that I have a higher force production (vs. trying to deliberately go slow) in the later sets (where I’m trying to push very hard and fast), which should result in quicker, more efficient inroad. I thought this was similar to what you were preaching prior to your recent Renaissance turn. Do you think this method still has merit or is it splitting hairs? Too dangerous?

    • Drew Baye Jan 31, 2012 @ 10:52

      Thomas,

      The general principle is the same, but there is no need to actually move faster during the last few reps. If the resistance selection is appropriate during the last few reps you will be contracting as hard as possible during the positive just to keep from going slower than 8 to 12 seconds and the last negative will require a maximum effort to perform slowly (relative to your momentary strength).

  • Craig Jan 30, 2012 @ 22:57

    I was under the impression that the original super slow protocol did call for relatively long TUL, up to 3:00 minutes for 8+ reps. I also had the impression that the RenEx folks (SuperSlow reinvented?) were now suggesting a somewhat shorter time, and fewer reps, so I was not sure if they had changed philosophy over time. Then I happened to see a post about slow protocols on a thread over at that other HIT blog (Darden’s). Josh Trentine just posted a quote from the 1989 edition of the super slow training manual. I’ll reproduce it here since it seems relevant:


    But here is a history lesson for you, straight from the book:

    “We desire momentary muscular failure to occur within an ideal range of 40-70 seconds. This ideal range is often adjusted upward for the novice (4-8 repetitions or 80-160 seconds), but for the sake of this discussion assume the lower and upper guide times to be 40 and 70 seconds and the lower and upper guide numbers to be 2 and 5 repetitions.”

    From Appendix: B Super Slow Protocol Second Edition 1989. First question under the Question and Answer section:

    Question: Doesn’t Super Slow training require more time to perform than the conventional lift-in-two-seconds-lower-in-four-seconds approach?

    Answer: No. Super Slow requires the same time alloted to the set and the complete workout as the conventional method. The common repetition scheme of 8-12 repetitions for the standard protocol represents a window of time to achieve momentary muscular failure in approximately 70 seconds. This is the time frame we strive for in the Super Slow application.
    ===

    So it does get confusing. You’ve got folks well versed in super slow history suggesting TUL ranges from 40-70, all the way up to 160-180 seconds. Perhaps part of the confusion comes from differentiating between novice, old or severely deconditioned trainees, and fitter, more experienced lifters. Even so, the figures you quote are above the high end of the range that was supposedly given in the 1989 manual.

    I’d guess most could use significantly heavier weight with 2 or 3 reps to failure versus 8. My inclination would be to favor heavier weights and fewer reps, if only because trying to move a weight slowly for 3 minutes can get pretty tedious. Intuitively, more tension also feels like the right direction to go.

    • Drew Baye Jan 31, 2012 @ 11:11

      Craig,

      The original guidelines were for a 10/4 speed to overcome some of the friction issues with earlier equipment, and a 3 to 5 rep range at 10/4 puts you in the 40 to 70 second range.

      The higher rep ranges evolved to allow for better learning and practice for beginners and to ensure resistance was not progressed unless a subject was capable of safely handling more resistance. The guidelines for more advanced subjects are lower, 3 to 6.

      Re-read what I wrote about weight versus relative effort. Relative effort is far more important, and while 100% relative effort can be achieved with varying levels of weight in the long run you’re better off erring conservatively.

  • Karthik Jan 31, 2012 @ 6:43

    Great info. Thanks Drew! And hats off to U for standing up to not just reconsider previous beliefs, but also accept changes in the presence of necessary facts. When “Exercise as a Science” is developed and formulated, the results will be there to see and experience for everybody. Thanks for the relentless pursuit and providing us an insight into your learning. Looking forward to EOF. When is it expected?

    • Drew Baye Jan 31, 2012 @ 11:52

      Karthik,

      You’re welcome, and thanks. I try.

      EoF is going to be done and finally out before the end of Feb. An announcement will be posted and updates to the pre-order page this week.

  • Drew Baye Jan 31, 2012 @ 9:48

    Vanner,

    Before I answer it’s important to point out the goal of proper turnaround technique is not to eliminate momentum, which can not be done, but to minimize acceleration to maintain a more consistent tension on the muscle for both efficient loading and safety. Momentum is mass times velocity; if there is movement there is momentum.

    If you take a similar time to accelerate to and from the average velocity at the turnarounds over a typical range of motion the variation in force in either may only vary by a few percent, but the slower you move the better your control and ideally the lower turnaround should take almost as long as the whole rep you are proposing in the second example.

    Also, there are other benefits of slower speed having to do with better feel for what is occurring and focus on the contraction of the target muscles over the range of the exercise.

  • Farhad Jan 31, 2012 @ 10:36

    Drew,

    Wouldn’t 3-minute TUL or even 2 for a specific muscle which is made of mostly FG fibers be too much? My current understanding is this kind of muscle should not receive a TUL longer than a minute because it may lead to atrophy over time.

    Also, any estimate on when Elements of Form will be available?

    Thanks.

    • Drew Baye Jan 31, 2012 @ 11:57

      Farhad,

      Some individuals might do better with slightly shorter, some slightly longer, but one to two minutes is not excessive. There is no reason to believe fast twitch fibers would atrophy with those rep ranges or set durations as long as the exercises are performed with a high level of effort, consistently and progressively.

  • Mariana Jan 31, 2012 @ 12:21

    Hey Drew,

    another great read, thanks a lot!
    I am just wondering about the relative effort, using the example of the leg press. Somehow I am quite not progressing with the weights when leg pressing, I am kinda stuck around 190 pounds by 11 reps. If I try to increase the weight (+5 pounds), the reps will drop a lot, so that I might get 5 reps at most and then somehow I dont feel that soreness as I could not walk, you know what I mean? It seems the scheme with the 11 reps “destroys” my muscles more than increasing the 5 pounds.

    Is this a common thing?! Cos I am a bit concerned that I am not being able to increase the weights lately. I know it might have do do with diet, recovery etc, but after reading this acticle, I am wondering “how crucial” it is to increase the weights lifted at all.

    Thanks, Mariana

    • Drew Baye Feb 1, 2012 @ 9:46

      Mariana,

      You may need to wait until you can perform more repetitions before adding weight or progress in smaller increments. There are a lot of different factors that can influence performance of a specific exercise and it’s hard to say without knowing more but I don’t want to get too far off topic here. If you want to discuss it I’m available for phone consultations.

  • Vanner Jan 31, 2012 @ 12:24

    Thanks for the quick response Drew – always insightful.

    Your clarification of momentum vs acceleration is something I’ll keep in mind when concerning a proper turn-around.

    Along with your Q&A post, I read the post on RenEx entitled “The Assumed Objective Versus The Real Objective In Exercise”, both of which helps clarify the true goal in exercise.

    It’s tough to step away from the idea of mechanical work (more lbs, more reps) since that is what has been traditionally used to track progress.

    I think I may try tracking TUL + lbs as a measure of improvement vs reps + lbs. This way I could step away from the thought of the rep count as a point of focus, and concentrate solely on working the muscle. I would also have my stop watch out of view — to also remove time as a point of focus.

    Note: I workout alone with a free weight setup.

  • Drew Jan 31, 2012 @ 15:48

    Drew,

    Awesome article!

    One question: For non skill-based training, why bother with full-range repetitions at all?

    Why not lift a weight to the position of greatest torque for a given exercise and maintain a static contraction until eccentric failure?

    Wouldn’t that be the most efficient way to work a muscle and also, one of the safest, as your avoiding unfavorable joint angles which can lead to bone-on-bone positions or overloaded tendons?

    • Drew Baye Feb 1, 2012 @ 11:21

      Drew,

      In some situations properly performed timed static contractions (as opposed to static holds) may be the best approach. However, in many compound movements (which are the most efficient way to simultaneously address a large number of muscle groups), the relative contribution of the different muscles involved can vary over the range of motion and a single position may not be equally effective for all of them.

  • Craig Feb 1, 2012 @ 12:14

    Mariana

    I went to an “A” and “B” workout so that I now do leg presses every 14 days and it has made a difference.

  • Vanner Feb 1, 2012 @ 21:56

    Hey Drew,

    In case it hasn’t been done in a while, I just wanted to drop you a thank you for your due diligence on this site.

    Your articles are well thought out and precise, and your quick response to comments really adds value to the topics at hand.

    Keep on, keeping on.

    • Drew Baye Feb 2, 2012 @ 12:09

      Vanner,

      Thanks. I try to respond to all comments and questions within 48 hours.

  • Matt Feb 3, 2012 @ 15:29

    Awesome article, just love your writing.

    One question, I’ve been reading a lot on lean gains.com and have tried the Reverse Pyramid on some exercises. On the leg press it produced massive fatigue, I’m still sore (not to the point of paralysis). What are your thoughts on such protocols? Doing the one, and only one, BBS style protocol seems inferior on the leg press, at least for me.

    • Drew Baye Feb 3, 2012 @ 16:35

      Matt,

      It is unnecessary to perform reverse pyramids. If the first set is done correctly, it is all that is necessary. More sets will not make a difference in growth stimulation while increasing demands on recovery.

      In all cases where I have trained people who believed they needed more than one set the problem was one of simply not doing the set hard enough. If you are ever in the Orlando area, please let me know and I’ll be glad to put you on our leg press and instruct you through one set that blows away any number of sets you’ve ever experienced with any other training protocol.

  • Brad Feb 3, 2012 @ 21:06

    Do you think that recommending a 10/10 rep rate can be counter productive as far as spreading the acceptance rate of HIT training to the masses of “normal” lifters? I mean, I think just getting them to accept 4/4 or 5/5 will be hard enough. Even myself, having bought into the effectiveness of HIT find a 10/10 rate quite awkward. Btw, is 10/10 considered “super slow”?

    • Drew Baye Feb 3, 2012 @ 22:16

      Brad,

      I’d rather provide the best, most useful information possible and only have a small minority of people accept it than compromise to appeal to a wider audience.

  • Matt Feb 4, 2012 @ 4:06

    I’d be glad to, unfortunately I’m located in Sweden. Would make an awesome holiday though 😛

    I understand what you mean there. My concern is if I can get to that level of effort when working out alone. On the other hand, I can’t do much more than push until I fail, while keeping form.

    • Drew Baye Feb 4, 2012 @ 11:15

      Matt,

      I wrote an article about this a while back I will update and repost soon on the proper mindset for high intensity training, which should help with this. Look for it to be up later this week.

  • Richard Feb 5, 2012 @ 4:05

    Just a suggestion, your website would read a lot better if your responses were indented underneath each users comment (conversation style) rather than sequentially as is the current style. Makes it hard to follow.

    • Drew Baye Feb 5, 2012 @ 11:35

      Richard,

      I agree. I will look into having that changed.

  • Richard Feb 5, 2012 @ 4:15

    Drew, would you recommend trap bar deadlifts over standard barbell deadlifts for a lower body pulling movement? Is there a better home exercise other than the deadlift for training low back and hams? I currently use a Super Squats hip belt for my lower body work but it doesn’t give me a sufficient low back/hams workout. Thanks

    • Drew Baye Feb 5, 2012 @ 13:03

      Richard,

      The trap bar is better than a barbell for deadlifts since it is easier to maintain a secure grip on and eliminates shin and knee clearance problems for longer-legged subjects.

  • Brad Feb 5, 2012 @ 13:36

    Drew, I don’t think you’d be compromising if you taught/allowed, or acknowledged the inevitability that people will use incorrect form (eg, 5/5 rep cadence, rest-pause, etc.) at least as a gateway to proper form. You’d be teaching how to “ramp up” to doing it right. Allowing both a mental as well as physical adjustment period. This is not unlike learning to perform many other sports.

    Take myself as an example. I’m 4 months into doing HIT. I’ve been doing mostly around a 4/4 cadence and rest-pause at times (not always, only when I feel I quit prematurely). While I have improved performance over these months I have also hit a plateau on some exercises. So now I will try decreasing weight, increasing TUL and slowing down my cadence to closer to 10/10 and see if that helps. If not, I’ll try modifying the types of exercises/machines.

    rgds, -Brad-

    • Drew Baye Feb 5, 2012 @ 14:10

      Brad,

      When I start working with a new client I anticipate it will take them a while to become proficient at performing the exercises and to learn to train intensely and achieve momentary muscular failure as efficiently and safely as possible. I don’t compromise and have them do less effective or less efficient things at first because they’re easier, I teach them how to do things correctly from the start and tell them to expect it to take time and practice to really do it well.

      Throwing in things like rest-pause or misusing other set-extension techniques like forced reps and drop sets would interfere with that learning, and distract from the real objective of exercise.

  • JF Feb 8, 2012 @ 17:48

    Hi Drew,

    I have a question about “good reps”:

    When I perform a set of let say pull downs and fail after 6 reps, I don’t seem to be able to execute the full range of motion for the last 3 reps. I would be able to go to 80% for rep 4, 70% for 5 and 50% for 6. All the negatives are under control. On rep 4, if I try to go to 100% range of motion, I’ll simply get stuck there forever and that will end the set. Is this normal. Should I just continue to pull on rep 4 until I can’t sustain it or is it better to do rep 4, 5, 6 at less than 100% range?

    JF

    • Drew Baye Feb 9, 2012 @ 15:54

      JF,

      It sounds like the resistance curve on the pull down you’re using doesn’t fall off enough towards the end point, otherwise you would be unable to perform additional partial reps after failing to complete the fourth. Rather than continue with partial repetitions continue to contract as hard as possible when positive movement stops. You might surprise yourself, and find you are able to complete the repetition. If there is no positive movement after ten seconds, gradually ease out of the position, slowly lower the weight and unload.

      • JF Feb 10, 2012 @ 9:19

        Ahhh. I see. Ok I’ll try that.

        Thanks!
        JF

      • marklloyd Mar 13, 2012 @ 11:57

        Why not hold static until a non-volitional lowering occurs?

        • Drew Baye Apr 16, 2012 @ 12:22

          Mark,

          Assuming an exercise is performed properly and intensely enough and for an adequate duration to begin with, holding for longer than 5 to 10 seconds after concentric failure appears to make a disproportionate demand on recovery while making little difference in results. Like many other set-extension techniques (forced reps, drop sets, post-failure rest pause, etc.) it tends to lead to overtraining.

  • Drew Baye Feb 9, 2012 @ 16:03

    Eric,

    We refer to the position you are talking about as the “end point”. The “mid point” is the middle position of the range of motion, not the point between the positive and negative movements.

    The squeeze is generally not performed on compound pushing exercises, and on other exercises it is only performed on the third and subsequent repetitions. At the end point of the first two repetitions you should perform a motionless hold in the most contracted position, but wait til the third repetition before performing a squeeze.

    If you aren’t getting at least 3 or 4 reps in perfect form, reduce the load. Don’t worry about this, though. Absolute load is not as important as relative effort. As long as you are achieving momentary muscular failure within a reasonable time frame the weight is heavy enough for best results.

  • Richard Feb 11, 2012 @ 3:49

    Drew, when performing the belt squat, I seem to reach failure in the bottom position (thighs parallel to ground) well before adequate inroad has occured within the muscles. I am over 6 feet tall and find that this mechanical sticking point is hindering progress with my legs. Knowing this, how would you suggest I train them using the squat belt? I am concerned with reducing the range of motion because I dont want to reduce with the efficacy of the exercise.

    • Drew Baye Feb 11, 2012 @ 19:20

      Richard,

      During compound pushing exercises with free weights or body weight the start point or a position close to it is where you encounter the greatest resistance due to the longer resistance moment arm, so it is normal for you to fail at or near this position. To efficiently inroad the muscles you must avoid portions of the range of motion where the moment arm is smaller and the target muscles aren’t meaningfully loaded. This is a case where increasing range of motion would make the exercise less rather than more efficient.

      • Richard Feb 11, 2012 @ 23:57

        But idealy, shouldn’t we be lifting and failing around the centre point of peak muscular torque rather than the maximum moment arm?

        • Drew Baye Feb 12, 2012 @ 0:41

          There is no advantage to achieving momentary muscular failure at any particular point in the range of motion. Theoretically, if using equipment with perfectly balanced resistance curves failure should occur at different positions randomly from workout to workout.

  • Richard Mar 4, 2012 @ 20:52

    Drew, I thought 5 sec holds were only intended for pulling exercises. Other than the squat, do you also recommend a five second hold for the Db shoulder press and Db bench press? If not, why?

    • Drew Baye Mar 8, 2012 @ 14:47

      Richard,

      I recommend the five second hold in the starting position of the body weight squat and other body weight pushing movements to increase the difficulty. During exercises performed with barbells or dumbbells the difficulty can be increased by using more weight, although I would still recommend a very brief pause at the start to ensure no bouncing, as long as the weight is not set down and the muscles are not unloaded.

  • Angie Mar 5, 2012 @ 11:28

    So will you send out a new download link when it’s ready?

    Thanks!

    • Drew Baye Mar 8, 2012 @ 14:48

      Angie,

      As soon as the digital version is ready a download link will be mailed out to everyone who pre-ordered.

  • Terry Wright Mar 15, 2012 @ 10:35

    Hi Drew!
    Thanks for all the great info your giving!
    Got a question:
    You wrote “Your muscles are actually capable of contracting with more force at slower velocities (do not confuse the velocity/force curve with the acceleration formula – they are two different things).”
    Could you expand on this more? The force velocity curve shows that the higher the given force, the slower the velocity will be however, isn’t this with the assumption the weight is being lifted as fast as possible? This would mean that at maximum voluntary contraction the higher the load, the slower the lift and more force production. The lift is performed slower unintentionally due to the load rather than intentionally. With the same max voluntary contraction the lighter the load, the faster the lift and therefore less force production.

    These are some of the questions/ arguments against lifting slow that I’m reading in research articles. I myself use a lifting cadence of 5/5 and I prescribe this cadence to my patients as well.
    Any info regarding the subject would be great!

    Thanks and keep up the good work!

    • Drew Baye Apr 3, 2012 @ 10:43

      Terry,

      The force/velocity curve describes the relationship between a muscle’s concentric contraction velocity and the force it produces. The slower a muscle shortens the more force it is capable of producing, theoretically due to greater cross-bridging.

      The force/acceleration curve describes the relationship between the force applied to an object and it’s rate of acceleration. The more force you apply to something, the greater the rate of acceleration.

  • marklloyd Apr 6, 2012 @ 10:47

    My most recent session, on chest press & pulldowns, my trainer added a few ozs of help to put me back into strong position, (after concentric failure & a few secs of static hold). I continued to exert full effort during the assist. I then did a static & c10sec non-volitional eccentric. Subjectively, this was very effective, removing any doubt of whether or not I’d given my best effort. I can see that if a set was already long, this would be too much, but after 3 good reps/60secs, it totaled less than 80secs. Any thoughts?

    • Drew Baye Apr 9, 2012 @ 9:58

      Mark,

      I do not recommend using rep-assist techniques. They tend to interfere with learning to inroad deeply. Better to leave them out and simply train to failure followed by a brief static contraction just to be sure.

  • james spella Apr 30, 2012 @ 5:11

    excellent article! it makes perfect sense especially in the context that we all structurally have limitations,i.e. we can’t gain more strength forever. safe and effective!