How many sets per exercise

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How many sets per exercise? What is the ideal number of sets per exercise, and does this also depend on the training goal and the experience of the athlete?

How many sets per exercise?

When evaluating the efforts made during a workout, you mainly look at two variables:

• Intensity
• Volume

The intensity is the resistance and/or speed with which an exercise is performed. This can be determined by the weight you train with. Because ‘force’ is the result of mass x acceleration, the speed at which you perform the exercise also makes a difference. An explosively performed exercise requires more effort than the same weight moved more slowly (in the concentric phase).

Training Volume: Number of exercises, repetitions, and sets

In this article, we mainly focus on volume. The volume of a workout is determined by the amount of work performed. Think of the total number of exercises (whether per muscle group or not), the number of sets per exercise, and the number of repetitions (‘reps’) per set. For example, during a workout, you can do 6 exercises, 4 sets per exercise, and 10 repetitions per set. Ten sets of 4 repetitions would result in the same volume, but would again result in a significant difference in intensity. Doing four repetitions (with the appropriate weight) changes the ratio in which certain muscle fibers are activated and thus the training goal (maximum strength instead of muscle mass).

Time under tension

Another variable that also affects volume is the so-called (total) time under tension. For example, a quickly performed exercise may mean higher intensity, but also lower volume. The muscle remains under tension for a shorter period during the executed repetition. Of course, this also reduces the total time during which the muscle is brought/kept under tension throughout the entire workout.

How many sets per muscle group?

A question I sometimes get asked is, “How many sets should I do per muscle group”. I think that’s not the right question. Because the right question itself turns out to be very difficult to answer, you don’t make it easier for yourself by starting with the wrong question. Ultimately, you want to know what happens with a specific group of muscle fibers that have exactly the same function. After all, you want to know how heavy and how often specific muscle fibers can be loaded for a certain result. Then you can’t add up sets where the same muscle fibers are used 20% of the time one time and 95% the next time (because you add two sets of two different exercises together).

Muscle group, muscle head, or muscle fibers training?

Suppose we fill in shoulders as the muscle group for this wrong question: “How many sets should you do for the shoulders?” The deltoid, the shoulder muscle, consists of three different so-called ‘heads’ (pars clavicularis, pars acromiaca, and pars spinalis). The muscle fibers originate from three different parts of the skeleton (‘points of origin’). All three are then attached to the same point on the humerus (‘point of insertion’). This means that pulling can be done from three different directions to the same point. This means that these different heads can be activated with different movements. Many shoulder exercises require the most from the front head, but some exercises shift this emphasis to the middle head (pars acromiaca) and/or rear head (pars spinalis). Does it make sense to ask how many sets are optimal when you don’t distinguish between these different heads and their functions? No, of course not. What you really want to know is how many sets you need to do to stimulate exactly the same muscle fibers the best for growth.

How many sets for muscle mass?

You also need to clarify what your goal is before asking for the ideal number of sets. For muscle mass, we often do sets of 6 to 12 repetitions because at that load, especially the type of muscle fibers that have the potential for growth are activated. For maximum strength, this number of repetitions is lower, somewhere between 1 to 6 repetitions. With fewer repetitions, you can do more sets and still achieve the same total volume. So, it is not inconceivable that the optimal number of sets for maximum strength is higher than the optimal number of sets for muscle mass. However, this is not necessarily the case. A recent study showed that a higher training volume, through a higher number of sets, does lead to more muscle growth, but not to more muscle strength [1]. One set, three sets, or even five, for muscle strength, there would be little difference. Unfortunately, studies in this area show many different outcomes. This is not very strange due to the large number of possible ways in which such a study can be set up. However, not all different outcomes can be explained by differences in the setup of the studies.

the preponderance of evidence suggests that for training durations of 4 to 25 weeks there is no significant difference in the increase in strength or hypertrophy as a result of training with single versus multiple sets. Because of the design limitations of these studies, conclusions concerning the efficacy of multiple sets should be tentative. However, there is little scientific evidence, and no theoretical physiological basis, to suggest that a greater volume of exercise elicits greater increases in strength or hypertrophy. R.N. Carpinelli, Adelphi University

Conclusion

A clear answer cannot be given. Some researchers attribute the different outcomes to differences in the study’s setup. Consider, for example, differences in the muscles trained and measured. Also consider differences in the type of training (full body vs. single joint). Or differences in participants’ experience and differences in the weight they train with and number of repetitions performed per set. The only thing you know for sure is that you cannot definitively say that a certain number of sets is best. Whether it is for muscle strength or mass. There is simply too much uncertainty about that.

References

1. Schoenfeld BJ, Contreras B, Krieger J, Grgic J, Delcastillo K, Belliard R, Alto A. Resistance Training Volume Enhances Muscle Hypertrophy but Not Strength in Trained Men. Med Sci Sports Exerc. 2019 Jan;51(1):94-103. doi: 10.1249/MSS.0000000000001764. PubMed PMID: 30153194; PubMed Central PMCID: PMC6303131.
2. Radaelli R, Fleck SJ, Leite T, Leite RD, Pinto RS, Fernandes L, Simão R. Dose-response of 1, 3, and 5 sets of resistance exercise on strength, localmuscular endurance, and hypertrophy. J Strength Cond Res. 2015 May;29(5):1349-58. doi: 10.1519/JSC.0000000000000758. PubMed PMID: 25546444.
3. Ostrowski, Karl & J. Wilson, Greg & Weatherby, Robert & W. Murphy, Peter & Lyttle, Andrew. (1997). The Effect of Weight Training Volume on Hormonal Output and Muscular Size and Function. The Journal of Strength & Conditioning Research. 11. 10.1519/1533-4287(1997)011<0148:TEOWTV>2.3.CO;2.
4. Carpinelli RN, Otto RM. Strength training. Single versus multiple sets. Sports Med. 1998 Aug;26(2):73-84. Review. PubMed PMID: 9777681.