How many Sessions?
How many times a week should we train in order to increase muscle size? What does the science show? In order to get an answer, we turn to a 2016 review paper by Dr Brad Schoenfeld and colleagues published in the journal: Sports Medicine, and also to the Position Stand of the American College of Sports Medicine entitled: Progression Models in Resistance Training for Healthy Adults. The main summary points are found below.
- Training a muscle group twice a week seems to be superior to once a week for gaining muscle size.
- It cannot be conclusively stated whether three times a week is superior to twice a week
- The science does not allow us to conclude whether four or more sessions/week for a muscle group is superior to two or three sessions a week.
- When comparing two groups, it seems that the number of sessions may not really matter if the total volume of training between the two groups is the same. Which is to say, even if group A does only one session for each muscle group and another does several sessions a week, the gains may be the same if the total amount of training accomplished is equivalent.
- Anecdotal evidence of body builders shows that many train each muscle group only once a week.
American College of Sports Medicine recommendation:
Novices: 2 - 3 whole-body sessions a week
Experienced: increased number of sessions using a split routine (ex. upper/lower body split routine).
More science is needed in order to make concrete recommendations. For now, it seems that training each muscle group at least twice a week is a goal to strive for. But keep in mind that just going to the gym is of no avail if one is not training meaningfully during the session. Remember that when volume (total amount of training) is the same, the frequency may not really matter. This is how for instance body builders can do only one session per muscle group but still build mass. Why? Because during the one session, they train meaningfully (ie. hard).
American College of Sports Medicine position stand. Progression Models in resistance training for healthy adults. Med Sci Sports Exerc. 2009 Mar; 41(3):687-708
Schoenfeld, B et al. Effects of Resistance Training Frequency on Measures of Muscle Hypertrophy: A systemic Review and Meta-analysis. Sports Medicine (2016). 46:1689 - 1697