Longer Rest Between Sets Enhances Muscle Growth
Certain people can develop a routine in the gym whereby their rest period between sets is decided upon by the limited amount of time they have available or just their overall work ethic. Some guys prefer a more circuit/superset style workout with little rest as they feel they get more of a cardio-based workout. If muscle growth or strength is the goal then it may be of interest that a longer rest interval in between sets is needed.
Twenty-one young resistance-trained men were randomly assigned to either a group that performed a resistance training (RT) program with one-minute rest intervals (short) or a group that employed three-minute rest intervals (long). All other resistance-training variables were held constant. The study period lasted eight weeks with subjects performing three total body workouts a week comprising 3 sets of 8 to 12 repetition maximum (RM) of seven different exercises per session.
As expected, maximal strength was significantly greater for both 1RM squat and bench press for the group taking a longer rest. Muscle thickness tended to be greater when taking longer rest intervals as well. Very short rest periods may compromise growth by reducing the amount of weight you can use on subsequent sets. These results may be due to a reduction in total volume load (i.e., reps × load) over the course of the study. This would indicate that if there are synergistic benefits to heightened metabolic stress, they are overshadowed by the associated decreased volume.
Results showed that a three-minute rest in between sets enhanced muscle strength and size compared to one minute. These results must be taken into context and realize that you should not wait three minutes between every set of each exercise. You should try combine different rest periods to potentially maximize hypertrophy.
In simple terms, take longer rest intervals (two to five minutes) on your compound exercises such as squats, bench presses and rows. These movements highly tax a range of muscles, predominantly when performed with moderate rep ranges (i.e., 8 to 15 reps). Thus, it may be best practice to incorporate longer recovery periods when performing these exercises to fully restore energy levels for your next set to ensure that volume load is maintained across sessions.
Conversely, exercises such as biceps curls, triceps press-downs and leg extensions are not as metabolically demanding and therefore could conceivably benefit from shorter rest periods. Thus, you can increase metabolic stress and its potential hypertrophic benefits without negatively impacting volume load. At the end of your workout would be the best time to utilize the short-rest sets to ensure they don’t interfere with recovery of compound exercise performance.
Steve O'Mahony BSc MSc
Schoenfeld B, 2016. Longer Inter-set Rest Periods Enhance Muscle Strength
Hypertrophy in Resistance-Trained Men. J Strength Cond Res. 2016 Jul;30(7):1805-12