Bodybuilding Basics: Sets & Repetitions

How many repetitions and sets produce optimal muscle growth (muscle hypertrophy)?

How Many Repetitions Should I Do?

This depends on your objectives and level. The usual method is to work with percentages, taking 100% as the maximum weight you can lift in a single, properly executed movement. A beginner will achieve some hypertrophy (muscle growth) at 50% of his or her maximum, but advanced athletes will not make much progress at this level.

Some approximate, basic statistical benchmarks for different objectives are as follows:

How Many Repetitions Should I Do?

This table shows why many people who want to increase the size of their muscles (hypertrophy) fail: they are outside the recommended margins of weight and intensity. If your goal is to achieve muscular hypertrophy, the effort made must go as far as “failure” (i.e., inability to go on) within the parameters indicated. If you find you can do more, it is because you are not using enough weight, or you are using impetus to complete the series (“cheating”). In this instance, the weight must be somewhat below the maximum. Furthermore, these are not closed-end ranges. Some positive results will be achieved if the percentage approaches either the upper or the lower level. For example, some degree of hypertrophy will occur whether you train at 87% or at 68%, but training at 100% or 10% will make no difference.

–For muscle hypertrophy (muscle growth/building muscle) use moderate loading (70 to 85 percent of 1 RM) for 6 to 12 repetitions per set. So if you want to increase muscle size, the majority of your training should be done in the range of 8 to 10 reps per set.

Remember, the best stimulus for inducing maximum muscular hypertrophy is to lift a weight equal to 70 to 85 percent of your 1RM repeatedly to failure – your last repetition is so difficult that you can’t squeeze out one more. During that last all-out effort repetition, the muscle is forced to contract all of its fibers. So at the point of momentary muscular failure, the maximum stimulus has been achieved, and your muscle will grow. No matter how many repetitions you do (8, 10, 11 or 12) always use a heavy enough weight so that the last rep is a struggle.

–If your primary goal is increasing maximum strength, then you should mostly train in the lower rep ranges (between 1-5 reps per set) and therefore at a higher intensity.

–If your primary goal is improving muscle endurance, then you should mostly train in the higher rep ranges (between 15-25 reps per set) and therefore at a lower intensity.

How Many Working Sets Per Exercise?

No study, of either trained or untrained individuals, has shown single-set training to be superior to multiple-set training; it appears that both types of programs are effective for increasing strength in untrained subjects (beginners) during short-term (6- to 12-week) training periods. However, some short-term and all long-term studies support the contention that a training volume greater than one set per exercise is needed for progressive physical development and improved performance. Each set of an exercise presents a training stimulus to the muscle; thus, once initial fitness has been achieved, performing multiple sets (three to six) with specific rest periods between them that allow for the desired intensity (resistance) is more effective than doing a single set. Most programs designed for the intermediate to advanced weight trainer incorporate between 3 to 6 sets per exercise. This set range is considered optimal for increasing strength. The number of sets per muscle group may range from 3 to 24 (for example is your train chest: 5 exercise x 3 sets per exercise = 15 sets per muscle group) but ultimately depends on the number of exercises performed for that muscle group, the number of muscle groups trained in that workout, the intensity used (the greater the intensity, the greater the stress placed on the muscle, and thus the lower the number of sets that should be performed), and where the person is in his or her training cycle.

Beginners can start with a single-set program (1 set per exercise) but they should progressively increase the number of sets per exercise to make further progress. Generally speaking, it is accepted that multiple sets are more beneficial for developing strength and muscle mass (hypertrophy). Most programs designed for the intermediate to advanced weight trainer incorporate between 3 to 6 sets per exercise. But on the end, the number of sets per muscle group ultimately depends on the number of exercises performed for that muscle group, the number of muscle groups trained in that workout, the intensity used, and where the person is in his or her training cycle. Train larger muscle groups with higher volume (higher number of sets). Larger muscle (which contains a greater number of muscle fibers) requires a greater stimulus to grow than a smaller muscle requires.

Summary: Optimal Hypertrophy Training Protocol

Sources:

-Hass, C.J., Garzarella, L., de Hoyos, D., and Pollock, M.L. 2000. Single versus multiple sets in long-term recreational weightlifters. Med Sci Sports Exerc 32:235-242.

-Campos, G.E., Luecke, T.J., Wendeln, H.K., Toma, K., Hagerman, F.C., Murray, T.F., Ragg, K.E.,
Ratamess, N.A., Kraemer, W.J., and Staron, R.S. 2002. Muscular adaptations in response to three different resistance-training regimens: Specificity of repetition maximum training zones. Eur J Appl Physiol 88:50-60.

-Chestnut, J.L., and Docherty, D. 1999. The effect of 4 and 10 repetition maximum weighttraining
protocols on neuromuscular adaptations in untrained men. J Strength CondRes 13:353-359.

-Gibala, M.J., Interisano, S.A., Tarnopolsky, M.A., Roy, B.D., MacDonald, J.R., Yarasheski, K.E.,
and MacDougall, J.D. 2000. Myofibrillar disruption following acute concentric and eccentric resistance exercise in strength-trained men. Can J Physiol Pharmacol 78:656-661.