Q:  I’ve seen some of the big guys at my gym doing super slow repetitions during their workouts. What’s the value in working out this way?

A: Super Slow training has been around for decades yet seems to be enjoying a recent resurgence in popularity. It involves controlling both the concentric (lifting) and eccentric (lowering) phases of a movement to such a degree that you are doing them in slow motion – that is, you are taking ten seconds to perform the concentric part of the movement and five seconds to perform the eccentric part. This compares with conventional training which advocates a two second up, one second pause and four second down cadence (most trainers abbreviate this dramatically). Advocates of super slow claim that performing an exercise in such a manner is far more productive than conventional training and, furthermore, that one set of four to eight repetitions is all that is required for maximum growth stimulation. Advocates believe this method is superior to conventional training in that it produces a superior impact on strength and muscle size, metabolic effect and body fat loss while providing a high-quality aerobic workout. To date, however, little scientific evidence has surfaced to support these claims.

One study that is cited by Super Slowers derives from a 1999 comparison of two groups of weight trainers over a 10 week period. The results, as published in the Journal of Sports Medicine and Physical Fitness, showed that the group who performed their exercises in super slow fashion had average strength increases that were 50% higher than the other group. These results were compromised, however, because the researchers did not use a standard test for strength for all trainees. The super slow trainers were tested for a 5 rep max at super slow speed whereas the other group was tested at a 10 rep max at the conventional training tempo. It was also noted that of the 147 people who trained under the super slow system, only one of them wished to continue training in that manner. The most commonly cited reasons for not wishing to continue were that super slow was too tough and too tedious. Many experts have also questioned the claimed aerobic benefits of the super slow method. In fact, a  study conducted at the Human Studies Department, University of Alabama at Birmingham, compared metabolic differences between super-slow and traditional weight training and found that both “metabolic and cardiovascular stimuli were low with super-slow training.” Researchers concluded that traditional resistance training “increases energy expenditure more than super-slow training does.”

So, then, is there any value at all in super slow training?

The whole basis of super slow is that you take all of the momentum out of the rep and put the full tension on the muscle. That sounds like a good thing and it is. However, can you imagine doing your one rep max on the bench press with a 10 second upward push? I bet not. In fact, studies have shown that the 10-4 cadence can only be maintained over a 6-8 rep range by dropping the weight to about 25% of one rep max. So, clearly the price to be paid for that slow movement is a dramatic decrease in weight lifted. And, while eliminating momentum is a laudable goal, do you really have to stretch the rep out to fifteen seconds to achieve this? Of course not.

Super Slow advocates are quick to point out that their system is safer than conventional training methods because there are no ballistic movements to cause injuries. There is certainly some validity to this – you just need to step inside any gym to realize that slowing down will prevent a lot of injury – but, again, it seems that 15 seconds is taking things a bit far. However, super slow has it’s own potential danger – elevated blood pressure. A ten second concentric lift would be very close to a series of isometric contractions that gradually move through an arc. Isometrics has been well documented to increase blood pressure levels. Yet, in a typical super slow workout you would, in effect, be doing hundreds of isometric contractions. The potential ramifications on blood pressure are definitely a worry. In fact, a study on this very matter, conducted by Professor Richard Hughson, President of the Canadian Society for Exercise Physiology, found that during a super slow leg press workout the trainee’s blood pressure was measured at a staggering 270/170!