Part of me cringes every time someone asks me how long they should rest between sets.

Rest periods are all but an extinct method of overload that most people just assume they don't need to pay attention to. These days rest periods are for checking out some chick or playing with your iPod.

Just look at how many articles have been written on rest periods. Not many. Everyone wants to know how many sets and reps they should do to build Schwarzenegger-like biceps, or which exercises are the best for six-pack abs.

If you actually pay attention to other people in the gym, you'll notice a weird sequence of events at the end of their set. The set ends, they wander around, have a posedown between their biceps, or hit the water fountain, then they start another exercise or another set of the same exercise.

Unbeknownst to most, rest periods are a critical part of defining the body you want, and there's actually a science behind it, too.

What We Know About Rest

Rest Interval Fact #1: The amount of rest parallels your training goal.

You've heard this one, right?

"Rest for 30 seconds if you want to burn fat, and rest for 60 seconds if you're trying to get strong."

That's sort of on point with what I'm talking about. Rest periods and their relation to training goals have been one of the most heavily researched topics in strength training history. If your training is taxing the nervous system, like it would be in lower rep, higher weight work and more explosive training, then you want full recovery so your rate of force development can be at its highest.

If you're trying to look good naked, then you want to keep the lactic acid high and your blood pH low, so you keep your rest periods short.

Rest Interval Fact #2: Rest periods affect your hormone levels during training.

Brought to the forefront when Charles Poliquin released German Volume Training, rest periods around 30 to 45 seconds optimize our growth hormone output, which helps us build muscle. The longer rest periods (60 seconds plus), while minimizing our hormonal response, increase our nervous system recovery.

Okay, so those are about the only two facts that are universally accepted for rest periods. A bodybuilder who's trying to gain size might keep his rest high, around 60 seconds, then drop them to 30 seconds when he supersets his training and wants to get lean.

A New Approach to Rest

Rest is another overload method. It's another way to grow and another way to lose fat. By dropping your rest by five seconds every week, it'll lead to more calories burned and a more intense workout.

There are a few other ways to use rest intervals to get jacked and shredded, so let's continue.

New Rest Period Law #1: Match the rest to the range of motion of the exercise.

So taking one of the two above facts, if you were a dieting bodybuilder, then you'd rest 30 seconds after a squat and 30 seconds after a curl. Sounds dumb, right? Well, that's what you've been doing for years, so why change now?

A movement like a deadlift not only recruits more muscles, but also works more joints through a longer range of motion, recruits more of the nervous system, lowers blood pH, and creates more fatigue substrates in the associated muscles. All of which are good reasons why you should take longer to regroup.

On another note, should the rest be different if you're doing dumbbell curls versus barbell curls?

You bet your ass it should.

The dumbbell work is more demanding on the body. You have to stabilize each scapula on its own, which can be harder than you think with today's posture, and each biceps and synergist forearm muscles must do more work without relying on the other side.

I'm not going to lie and say that I have exact rest periods down for a deadlift versus a curl. But regardless of the training purpose, rest a minimum of 60 seconds for the deadlift and 45 seconds maximum for a curl.

New Rest Period Law #2: Match the rest to the amount of muscle recruited.

This is a simple offshoot of the above law, but looking at the deadlift versus curl example again, you're talking about resting the same for an exercise that recruits our quads, hamstrings, and glutes, which are all massive, versus our biceps and some forearm flexors.

It's like training with full body workouts five days a week versus training with body part splits five days a week. Which workouts do you think are going to be more productive?

Even without researching the massive effects of the central nervous system, you can tell that the answer is going to be body part splits. Being that we recruit less total muscle with body part splits, we can go to the gym and train hard more often.

It's the same for matching the rest with the amount of muscle recruited. It's going to take a lot longer for our central nervous system to recover with a deadlift.

New Rest Period Law #3: Match the rest to the individual.

This is my biggest beef with the typical rest recommendations. I'm 6'6", 240 pounds, with evenly proportioned limbs, should I be resting the same as someone who's 6'0", 210 or 5'9", 170? What about someone who's 6'6", 240, with short legs and long arms?

The answer to both questions is no.

Even someone who's the same height and weight as I am, but has longer arms and shorter legs, is going to require different rest periods.

Why is it that the big guys are always the last ones down the court in basketball? Weight, height, limb length, muscle size, and age are all factors that have to be accounted for. The same is true with dieting advice. You can't just tell someone they have to eat 120 grams of carbs per day without factoring in everything.

I'll have to go through a longer range of motion on a squat than a 6'6", 240-pound guy with short legs, and he'll have to go press further than I will, so do you think we should rest the same?

Again, I wish I had a definite table to give to you, but it's just too variable to predict.

New Rest Period Law #4: Match the rest to the training progress.

If you've been training for a while and are past the beginner stage, then you should really consider using this principle now. Progressively lowering the rest intervals during the workout, or from workout to workout, will increase your progress since your ability to buffer lactic acid adapts to your amount of muscle and your blood lactate levels.

Dropping the rest between sets increases your natural growth hormone levels and increases blood flow to the working area, which will also increase your anabolic response to training. Neither of which are monumental, but they surely can't hurt your training efforts.

As a general rule of thumb, begin by dropping your rest five seconds between sets, ending at 20-second rest periods. Anything under 20 seconds of rest is foolish, so start higher with your rest periods and slowly drop it down. Also, you don't have to drop the rest every set, aim for three or four evenly spaced out five-second drops during your entire training session.

After about four to six weeks of dropping your rest the same each workout, you can try something more advanced.

Set

Rest

1

45

2

40

3

35

4

30

5

25

6

20

Don't knock it until you try it. It'll leave you pumped and swollen like all those nitric oxide products promise.

I wouldn't suggest the advanced lifter perform this rest period technique on an exercise that requires intense muscular coordination like deadlifts or snatches, but anything from squats on down is open season.

The Nutrition Factor

If you're going to play with your rest periods, then you must have adequate supplementation, since you'll fatigue a lot faster than normal and your ability to train at a high level will be impaired.

Never stop training hard.

I originally used branched chain amino acids (BCAA's) during my workouts where I dropped my rest intervals, and they're excellent for preventing muscle breakdown, but I don't think they're necessary per se for this type of training.

In my opinion, you gotta turn to Rhodiola rosea after these intense sessions.

The human body is designed to maintain homeostasis at all costs, so when you suddenly change any of the intensity methods in your training, the body will respond by releasing ugly cortisol in response to the new level of stress. On top of reducing cortisol, Rhodiola will also make you feel better about thoroughly trashing yourself post-workout. Double benefits never hurt.

Closing It Out

Even if you don't love my recommendations for handling your rest intervals, what've you got to lose? Chances are at some point you'll need to break out of a training slump and doing more sets or reps is so old school and won't work forever.