If you want to get big, you must be patient.

I’m not just talking about the months and years it takes to build significant muscle mass, but being patient before jumping into your next set, because if you’re not taking sufficient rest between sets, gains will suffer.

This is the finding of a study of 16 young men published in Experimental Physiology. The study used 75% of the participants 1 repetition max for resistance (in what is commonly referred to as the hypertrophy, or muscle-building range). They compared taking a one-minute rest between sets with a five-minute rest, and discovered that the shorter rest period blunted muscle protein synthesis and anabolic signaling. That means less gainz, bro.

But five minutes between sets? Who has that kind of time?

A study of 21 men conducted published last November in the Journal of Strength and Conditioning Research looked at one vs. three minute rest breaks, again training in the hypertrophy range, and found that the longer rest period enhanced gains in both muscular size and strength.

I spoke with the lead author of the latter-mentioned study, Brad Schoenfeld, an assistant professor of exercise science at Lehman College in New York and author of the M.A.X. Muscle Plan, to get more details about just how much difference a longer rest period makes.

“There is a substantial difference,” Schoenfeld told me. “The effect sizes are very meaningful showing that longer rest intervals between sets have an advantage for hypertrophy.” He added that a one-minute rest interval while training in the hypertrophy range is considered quite short, and certainly seems to compromise muscle growth.

But can you cut it even shorter than three minutes? Probably.

“Another study compared two minute vs. five minute rest breaks and did not show a difference, so by process of elimination I would conclude that two minutes is probably sufficient to not have a detrimental effect on hypertrophy,” said Schoenfeld.

So, when training for size, two minutes between sets should be enough to maximize gains. Now let’s try to understand why.

“The volume is less with the shorter rest interval because you’ve compromised your ability to recuperate for the next set,” Schoenfeld said. This means that if you do a set of 10 reps, then only rest a minute, you might only be able to do six or seven reps on the next set because you didn’t rest long enough to be ready to go again. If you had waited another minute you could have hit nine or even 10 reps on the next set. That’s more total volume, which = bigger gun show for you.

Schoenfeld wanted to be clear that this involves some speculation, but logically he can’t think of an alternate hypothesis to explain it. When you lengthen the rest period it does have the effect of reducing metabolic stress, which is shown to have a positive effect on hypertrophy, but he explained that it seems as though the reduction in volume overrides any positive effect of the increased metabolic stress of the shorter rest interval.

What if you want to wait even longer?

“Will longer rest have a negative effect beyond a certain point?” Schoenfeld asked. He then answered by saying, “We can’t say that to be true. Is there a sweet spot? That’s a possibility, but we can’t conclude it yet.” We’re not certain if, when focusing on a rest period that allows for high volume lifting, if metabolic stress is additive or redundant. But again he brought up another study that showed there wasn’t any difference between a two-minute rest period vs. a five-minute rest.

So, if you’re one of those guys who like to “chew the fat between sets,” as Brad puts it, then “there might not be negative effects from resting longer.” The real question is, do you want to take three-hours to get your workout done?

It is important to know that the study involved going to concentric (going against gravity) failure. And by failure that doesn’t mean as many reps as humanly possibly via flopping around like a spider monkey on a meth bender to bang out one more rep. It is failure while maintaining good form. If you’re not training to failure then you may be able to take a shorter rest interval because there is less exhaustion and likely less detrimental affect on volume.

Not long ago I switched to total body workouts because I have a home gym and can monopolize the shit out of everything without being called a squat-rack-hogging douche. I do this by never taking rest breaks. Sets of bench press are interspersed with squats. Sets of chin-ups are alternated with sets of lunges. Rows are alternated with push-ups …

And that’s just fine, Schoenfeld says. “By alternating pushing and pulling / agonist and antagonist, you can stave off the need to take any rest interval. It’s very efficient, although you may need some short rest breaks to catch your breath.”

He was right about that. For the first month this approach was brutal, but eventually I adapted. And being alone in the basement gym means no rest intervals is a real boredom killer.



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James S. Fell, MBA, writes for the Los Angeles Times, Chicago Tribune, Women’s Health, Men’s Health, AskMen, the Guardian, TIME Magazine and many other fine publications. His first book was published by Random House Canada in 2014. He is currently working on his next book, which is about life-changing moments.