In May of 2001, Muscular Development magazine ran a feature on SuperSlow® training , in which contributing editor Bob Lefavi, PhD. interviewed Dr. Wayne Westcott, Dr. William Kraemer, Dr. Robert Newton, and myself. The following is the portion of the article with my interview, followed by my current thoughts on the subject.
I still think the TUL’s [time under load; beginning to end] that people use with SuperSlow® are too high. But, it’s not so much a problem with SuperSlow as it is with the way it’s being applied. My personal experience has shown that the six to eight rep range, while producing significant improvements in other trainable areas of fitness, is less than ideal for someone trying to gain muscle mass, for a few reasons.
First, obviously, if you’re spending 120 to 180 seconds performing an exercise, you’re not going to use nearly as much weight as you would if you were trying to fail in a lower TUL. Second, it unnecessarily increases the overall volume of the workout.
Ken’s [Hutchins] experience with rehabilitation and training osteoporotics has led him to be more acutely aware of the potential for injury in some subjects during exercise when poor form and typical movement speeds are used. It’s an irrefutable fact that when a material is exposed to a level of force that exceeds it’s structural strength, it fails, and that force = mass x acceleration. The principle, that slower movements are safer, is a given.
The principles behind SuperSlow are sound. If there are any problems, it’s in the application. Obviously, younger, stronger athletes are structurally far more sound than the elderly and injured that Ken has spent much time working with. I believe a moderate, but not quite as slow rep speed would still be safe, but more efficient in terms of keeping TUL lower, while still providing enough reps per set to be safe.
In any case, slower is safer, and slow movement loads the muscles more efficiently because there’s less momentum. He’s right about that. How much slower? I would have to say that like everything else, it’s an individual thing. In my opinion, a big part of the problem with a lot of things is that people want instructions, not understanding. They want to be told exactly what to do, but not have to think too hard about it. Problem is, in so many endeavors, the proper action is context sensitive. while the same principles apply, their applications will be different for each person’s unique situation.
It is true that there’s no one program to fit everybody, if you define “program” as a specific set of actions (do this X number of times, Y days per week, at Z cadence, etc.). But, if you define a program as a set of principles to be applied based on each individual, then there can only be one program for everybody since we’re all physiologically pretty much the same (with much variation in form, but not in basic function). And we are all subject to the same laws of physics. The individuals simply have to do the work and experiment and find out how to best apply those principles within the context of how their bodies respond to training.
Is it important to move slowly during exercise? Yes, slowly enough that you are using your muscles to do the work and not exposing your body to excessive force. Is it necessary to move so slowly as 10/10? Probably not. It’s got a built-in margin of safety to compensate for those on the low end of the bell curve of structural integrity. There are other considerations, such as motor skills, but these are not fixed either. While it may be necessary for someone with poor motor control to move more slowly to really be able to focus on what muscles they’re using, someone with better motor control may not. Like the RDA is more than what the average person needs, so as to compensate for those on the higher end of the bell curve where nutritional requirements are concerned, I think the SuperSlow recommendation of a 10/10 rep is the same type of thing. My body’s daily requirement for vitamin B might be X, but if I take in a little more, it’s not going to hurt anything. My body may be structurally strong enough to withstand X amount of force, but it doesn’t hurt to reduce the force a little more, for safety’s sake.
Of course, continuing with the vitamin analogy, as you know, too much of some vitamins can be a bad thing. If a particular individual is using a particular rep cadence and some minimal rep range guideline for the sake of safety, but it results in a TUL/volume of exercise that is beyond what is ideal for that individual based on his tolerance for, and ability to recover from and adapt to the stress of exercise, then he may be going too slow. There are also motor control problems involved.
In any case, I think SuperSlow is based on sound principles, but individuals have to determine how to best apply them based on their particular goals and needs. In the case of a bodybuilding application of the protocol, I recommend using a much lower rep range and TUL than what the general, non-bodybuilding fitness-minded individual would use.
In short, I believe the SuperSlow exercise protocol, like HIT [High Intensity Training] in general, is not so much a fixed “program” as it is a set of principles, the application of which must take into consideration individual differences. I agree that change in a workout is necessary, but those changes should be in accordance with how one’s body is responding to the training, and in accordance with the principles of the protocol, which I believe to be absolutely correct.”