There are countless repetition schemes when lifting weights. None is necessarily superior to another, and, frankly, there is very little evidence to suggest any one’s superiority. In general, it all comes down to goals, preferences, and personal responsiveness.
In the most general sense, resistance training is performed for one of three purposes: muscle strength, muscle hypertrophy, and muscle endurance. Collectively, these serve to improve performance and body composition. Because every body and everybody is different, there are no single path(s) to accomplishing these purposes.
Muscle strength is defined as the capacity to exert maximal forces (as measured by the one-repetition maximum, 1-RM). To get stronger one must progressively overload the muscle’s capacity to produce maximal force. Simply put, to get stronger lift heavier weights. Training for strength generally falls in the range of 1-5 repetitions. There are limitless ways to accomplish this. There are arguments for and against high-frequency (greater than two training sessions per muscle group per week). There is always discussion about the number of sets. At the root of these questions is always recoverability. The goal is to recover and come back to lift more. Three to five sets seems to be the sweet spot. These are working sets, meaning we are not counting warm-up sets. Some might prefer “pyramid” sets (e.g., increasing the weight and decreasing the repetitions with progressive sets. Others prefer simply warming up to the prescribed sets and repetitions. Put a group of strength and conditioning coaches in a room and see how long it takes for them to come to an agreement.
Muscle hypertrophy is a bit more complicated. It sensible to consider that there are two types of skeletal muscle hypertrophy: myofibrillar and sarcoplasmic. Without going into an extensive discussion of anatomy and physiology, myofibrillar hypertrophy involves the thickening of the muscle protein myofilaments (e.g., actin and myosin), as well as the muscle connective tissues. Such hypertrophy is the result of muscle overload. It will be a outcome of most any strength training exercise—beyond the neural adaptations (e.g., increased motor unit recruitment). Sarcoplasmic hypertrophy is the increased muscle volume that results following certain types of training. This may or may not accompany myofibrillar hypertrophy.
It is probably an understatement, but myofibrillar hypertrophy is probably most connected to intensity, while sarcoplasmic hypertrophy is probably more associated with volume and time under tension. Thus, the power/strength athlete may get powerfully strong without getting tremendously large, and the bodybuilder may get freakishly large without getting powerfully strong. Volume and intensity are typically inversely related.
Muscle endurance is defined as the ability to contract the muscle repeatedly or sustain a contraction without fatigue. The strength-hypertrophy-endurance continuum runs from one to infinite repetitions (though infinity is a bit of hyperbole). I would make a case that muscle endurance training is performed under minimal load for the goal of increasing the number of repetitions or duration of the exercise as the principle adaptation. Muscle endurance exercise is also performed for the intent of caloric expenditure (burning fat) rather than building muscle strength/hypertrophy.
With the above definitions, it becomes apparent that question of repetitions performed in a set becomes a question of whether the set is being performed for strength or hypertrophy, and, if for hypertrophy, which type of hypertrophy. Since strength involves near maximal lifts, it should be apparent that a greater recovery is required between sets and, thus, the fewer sets that can be performed in a given workout (assuming that few of us have nearly all of our waking hours to dedicated to weightlifting). Thus, for strength, few sets and greater frequency can work. Simple effective schemes for those of us aging and recreational strength trainers include those such as the StrongLifts 5×5 and Wendler’s 5-3-1, about which I have written before. Pyramid sets (similar to Wendler’s 5-3-1) are also effective. For hypertrophy, however, it gets more complicated and arguable. As volume is the goal for hypertrophy, frequency will be less. (Some prefer 1-2 workouts per body part per week.) An argument can be made that the important factor in stimulating hypertrophy is fatiguing the muscle. Hence, we have philosophies like Art Jones’ one-set-to-failure concept from the 1970’s Nautilus (e.g., Mike Mentzer). Or there is the German High-Volume Method (10 sets of 10 repetitions). Most body builders will say that, for size, you need to keep the weights lower and the repetitions high and go for the “pump” or the “swole”. As such, one promotes greater sarcoplasmic hypertrophy. Which is best? I am afraid to stir that pot. What is best is what works for the individual. I have tried a lot of approaches with varying results. I don’t exactly have the genes for bodybuilding per se. I am just happy to make some gains in strength and see some modest level of hypertrophy.
As important—or perhaps more important—than the reps and sets and how they are performed is nutrition and recovery. One can crush the muscle with monster sets or breakdown routines, but to get big, it has to grow, and, to grow, it has to recover. To maximize performance, one has to cycle through periods of hypertrophy and of strengthening. Above all else, the work has to be done. So, do the work that produces the results you desire.
Be your best today; be better tomorrow.
Carpe momento!