When prescribing repetitions and sets, the strategy of periodization is a must. Periodization is the planned variation in training volume and intensity (Fleck and Kraemer, 2004). It is very common with the general population to place an emphasis on a high number of repetitions to “feel the burn,” and there is a popular myth that high repetitions make muscles lean, while high weight with low reps makes muscles bulky. However, that is not completely true. A good comparison to discuss is an Olympic weightlifter versus a bodybuilder. When watching the weightlifting competition in the Olympics, it is remarkable how strong the competitors are for their bodyweight. Even the lightweight elite level Olympic weightlifters can often be stronger than the massive elite level bodybuilders.
Bodybuilders typically stay with very high repetitions in their training program to break down muscle so it builds back up bigger. Olympic weightlifters are trying to get as strong as possible while staying as light as possible to keep themselves in their appropriate weight class. If they put on too much size, then they have to bump up a weight class where they will have to get much stronger to compete. Olympic weightlifters typically train with very low repetitions and very high amounts of weight. Training with high repetitions will cause an effect that breaks down the muscle so it builds up bigger. As the repetitions go down and the weight increases, this becomes more of a central nervous system function, where the neurons and fibers of the muscle are learning to fire for maximum strength and power, and does not cause the same breakdown and rebuilding of muscle tissue as the high repetition scheme does. The metabolism can stay high regardless of repetitions with appropriate rest intervals.
The beginning of the workout program should consist of high repetitions to increase the muscles’ work capacity and endurance (hypertrophy phase). This is also the phase where females will get “fit,” “firm,””and “toned.” Due to higher testosterone levels, this is the phase where a male will put on muscle mass. If you need muscle mass, then there should be an emphasis and perhaps some extra time spent on this phase with a weight gain nutrition program. It is also necessary to work through the entire periodization scheme regularly. No matter what your goals are, if you only work one number of set repetitions, your body will get used to this and stop adapting to perform better.
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Fleck, S. J., Kraemer, W. J. (2004) Designing Resistance Training Programs Third Edition. Champaign, IL: Human Kinetics.