To induce muscle hypertrophy, the muscle needs to be pushed to overload. This is achieved through progressively increasing mechanical tension. We can manipulate mechanical tension through the length-tension relationship (hypertrophy is greatest when training through lengthened positions), more time under tension (higher reps, greater range of motion, and maybe slower eccentric contractions), and the amount of resistance (through weight or bands). Do you measure all of these in the clinic? Research suggests your volume load (reps x sets x weight of resistance) should be tracked. Provided you train with a full range of motion and close to failure (1-3 reps left in the tank), volume is the primary variable to consider for your patients.
The amount of volume someone can complete is dependent on their training history. If a patient has never lifted a weight in their life, an hour session consisting of 8 different resistance exercises will lead to days of severe DOMS and a high likelihood of canceling future sessions. Conversely, TheraBand’s are unlikely to induce any meaningful adaptation for someone who regularly trains. So, what is the sweet spot? How much volume do people need for hypertrophy? This systematic review analyzed training programs with different rep schemes and training frequencies to determine whether the total number of sets is a valid method to quantify training volume for hypertrophy training.
This systematic review included 14 studies consisting of 359 trained athletes ranging from 19 to 34 years old. The authors found that the total number of sets is an effective measure to quantify training volume, provided a few key variables are met. If the goal is to increase muscle mass, most sets are between 6-30ish reps (the authors say 20+, I’m going off a recent Schoenfeld review), and the RIR is less than 4, then total sets are a good measure to use. So how many sets should we perform?
According to a 2022 systematic review by the same author, 12-20 sets per muscle group appear to be a solid starting point. A lot will depend on the training history of your patient. Unless they are a professional bodybuilder, it’s unlikely you need to exceed that. Keep in mind, that this is not 12-20 sets of any exercise, just exercises that meet the intensity threshold for hypertrophy. If you are working on graded exposure or cardiovascular capacity, your total exercise time may be higher. The dose should be specific to the goal and the individual you are treating.