Shortening Inter-set Rest Time Are Shortening Your Gains

Sets, reps, temp, exercise choice, exercise order, and all the other details that go into a hypertrophy program are all important in their own respects. What about your rest times between sets? Can you get more or less growth resting shorter or longer? Common practice in meathead world are drops sets, super sets, rest pause sets for more gains! How are these better than a straight sets with normal rest time? Duh, John its harder and makes you look wicked hardcore on IG. Point well taken, but I truly want to know how to make the most out of each set I do.

Making the First Set Count

Mechanical tension is the main driver of hypertrophy and this can be accomplished in a set by training with heavy or light loads as long as they are taken close to failure. Seems like the last few reps close to failure are the real reps that stimulate growth. Step into the real world what does this look like. Well John gets in his Leg press and cranks out 1 set of 800lbs for 14 reps, nothing left in the tank. Great, one hard stimulating set done, now John is panting on the floor praying for more oxygen. Is it better to rest 1 minute, 2 minutes, or 5 minutes before he jumps back into set 2 of 800lbs?

The Detriments in Short Rest Times

After the first set John completes, he reaches those high levels of mechanical tension but there is also a large accumulation of metabolites (burning muscle crap i.e localized fatigue), also a large amount of systemic fatigue which can decrease neural drive (i.e motor unit recruitment). So, go into set 2 too soon, say 1-minute rest while the muscle fatigue is high and neural drive is low, he might only get 7 reps. Sets to failure is not all that matters here, the quality of those sets does as well. With acute fatigue the hypertrophic effects of the reps close to failure becomes less effective. So, those last hard 3-4 reps are no longer stimulating the same growth response compared to if he took 2-3 minutes of rest. A longer rest and John would also get more reps maybe 10-12 on his second set. The rep drop off can be an issue if you drop below the rep range needed to accrue enough stimulating reps (5-6 reps). So if you are so fatigued you are only getting 1-2 reps per set, likely you will need a lot more of those typed of sets to accumulating enough stimulating reps.

How Long to Rest Between Sets?

In general, I would recommend 2-3 minutes between sets or a return to baseline heart rate and mental readiness. This will allow for enough fatigue to recovery to keep subsequent set performance high enough to achieve enough stimulating reps. Larger compound lifts might need slightly more time and isolation lifts slightly less. A deep dive for another day is on drop sets and rest pause sets but this might have the thinking wheels turning on the application of that. Till next time!

Train Hard!

John Jewett, MS, RD, IFBB Pro

Reference
Schoenfeld BJ, Pope ZK, Benik FM, et al. Longer Interset Rest Periods Enhance Muscle Strength and Hypertrophy in Resistance-Trained Men. J Strength Cond Res. 2016;30(7):1805-1812. doi:10.1519/JSC.0000000000001272