Starting your journey into health and fitness is a time of excitement, and it's also a time when you can be overwhelmed with questions, such as:
- What’s the right workout program for building muscle?
- What’s the best workout program for losing fat?
- Should I bulk or cut?
- What's the best pre-workout?
In addition to the above questions, another one of the most common questions beginners (and even well-seasoned gym rats) have is: how long should you rest between sets?
Traditionally, it was believed that shorter rest periods were good for building endurance and longer rest periods were best suited for building strength.
But, research has shown some interesting results in recent years, especially in regards to building muscle (hypertrophy), as it seems that both shorter (~1 min between sets) and longer (~3 min between sets) can produce similar gains in hypertrophy.
But, let’s not put the proverbial cart before the horse.
Before we answer, "how long should you rest between sets?" let's start by discussing the three central energy systems involved during exercise.
3 Energy Systems That Power Your Workout
Phosphagen System
Phosphagens are energy-storing compounds, also known as high-energy phosphate compounds, primarily found in muscular tissue. This includes both ATP (the primary “currency” of energy production) and creatine-phosphate -- the storage form of creatine in muscle tissue.
These high-energy substrates are the primary source of energy for muscle cells during intense physical activity (heavy weight lifting, sprinting) lasting up to 30 seconds; after this timeframe, the body starts to shift to other substrates (which we're about to cover) to generate the ATP required to continue doing work.
Additionally, it can take up to 5 minutes to fully replenish depleted ATP stores.
While the phosphagen system is incredibly powerful, its duration is brief. This is one of the main reasons individuals supplement creatine, such as SteelFit® Creapure®. Supplementing with creatine monohydrate helps increase muscle stores of creatine-phosphate, increasing how long you’re able to power muscle cells using the phosphagen system before switching to the “backup” fuel systems.
Speaking of which...
Glycolytic System
As the phosphagen system starts to dwindle, the glycolytic system is activated, supporting your muscles when they're under load between 30 seconds and ~2 minutes.
The glycolytic system (as you may have guessed) involves the breakdown of glucose (a glycolysis process), which is used to synthesize and regenerate ATP.
The glucose used to produce ATP comes from two primary sources -- blood glucose (aka blood sugar) or glucose stored in skeletal muscle tissue and/or the liver (also known as glycogen).
The body stores around 500 grams of glycogen, with about 100 grams being stored in the liver and the remainder reserved in skeletal muscle tissue.
The more muscle mass you have and the more experienced of a trainee you are, the greater glycogen storage capacity your muscles typically have.
Typical resistance training protocols (multiple sets of an exercise in the 6-15 rep range) rely primarily on phosphagen and glucose to satisfy skeletal muscles' ATP requirements. The more volume you perform, the more glycogen you deplete.
As glycogen stores begin to dwindle, fatigue can set in. To stave off fatigue, it can be helpful to have some carbohydrates pre-workout (such as a bowl of oatmeal + a scoop of SteelFit® Steel Whey®).
Another option, especially useful for long-duration training sessions or endurance activities, is to sip on an intra-workout supplement, such as a scoop of branched-chain amino acids (BCAAs) like Steel Fuel® and/or intra-workout carbohydrates.
Intra-workout supplementation can help prevent the body from breaking down skeletal muscle tissue for ATP by supplying the body with easily accessible energy sources. In addition to sparing muscle tissue, intra-workout supplements may also help delay the onset of fatigue, thereby allowing you to burn more calories and bang out more reps, which helps you ultimately get more results!
Oxidative System
After 2-3 minutes of continuous work, the body again starts to shift energy systems. It will still be burning glucose for some of its energy needs. Still, it will change most of its energy demand onto the aerobic or "oxidative" system, which uses fats, carbs, and, when all else fails, protein for energy.
The oxidative system is called into action during low-intensity activity (walking, steady-state cardio) or endurance training, such as doing a higher rep, lighter weight resistance training exercises with brief rest periods (30 seconds or less between sets).
Now that we've covered the basic energy systems used to power your muscles during exercise let's discuss how long you should rest between sets.
How Long Should You Rest Between Sets?
There’s no one-size-fits-all answer for this question.
It's going to depend on a couple of factors, including:
- Age
- Training experience
- Cardiovascular condition/fitness
- Training modality (strength, hypertrophy, endurance training, etc.)
- Time available to train
Since there are so many variables at play, we'll approach this from a "best practices" standpoint, assuming that you have sufficient time to train for the type of athletic performance and physique goals you wish to accomplish.
Note: one of the good things to keep in mind is that if you're purely interested in muscle building, you can accomplish it using both short rest periods (a la rest-pause or DC training) as well as more extended rest periods.
Short Rest Periods (about 30 seconds max between sets)
Short rest periods, generally those lasting 15-30 seconds, are typically recommended when you're trying to:
- Increase energy expenditure during training (more work can be done in the same amount of time when using shorter rest periods vs. more extended rest periods)
- Training to improve muscular fatigue (resting such a brief amount of time never gives the muscle a chance to recover fully
- Get in a quick circuit-style workout due to time constraints.
However, if building muscle and increasing strength is your goal, short rest periods may not be the “optimal” choice.
You see, the drawback to short rest periods is that they do not allow your muscles to recover before the next effort (working set) adequately. Jumping into your next set too soon, before your muscles have sufficiently recovered, makes them more tired, which isn't optimal for building pure strength (for hypertrophy, it can be OK). As such, you won't be able to perform as many reps or push as much weight as you could have you rested longer.
In other words, shorter rest periods are suitable for "fat loss" workouts (cardio, interval training, etc.) and endurance training but are less than ideal for pure strength building.
Moderate Rest Periods (1 to 2 minutes between sets)
Standard bodybuilding protocol has always subscribed to moderate rest periods to maximize the pump, force the muscle to perform as much work as possible in a limited amount of time, and take advantage of the spike in growth hormone that typically accompanies moderate rest periods.
For a long time, it's been the belief of many that reasonable rest periods allow just enough recovery to perform a quality set, yet not enough to where the muscle completely recovers from one set to the next.
This was believed to be the "sweet spot" for muscle building, the proverbial "Goldilocks" where the rest isn't too long (strength) or short (endurance); it's just suitable for building slabs of lean muscle mass.
The moderate rest approach has worked for many lifters over the years and can work for you too, but there might be some advantage to be gained from resting just a bit longer, as you'll see in a moment.
Long Rest Periods (3 to 5 minutes between sets)
Long rest periods of 3 to 5 minutes have been the de facto rest interval length for powerlifters and strongmen athletes looking to increase strength.
The primary advantage of long rest periods is that muscles can recover their strength and replenish ATP levels, meaning you can move near maximum weight in subsequent sets and tap into those fast-twitch muscle fibers (the ones that are better suited to growth).
The drawback to long rest periods is that most people don't have endless hours in a day to work out, so while long rest periods are good for increasing strength, they cannot get in enough volume to stimulate adequate hypertrophy.
Upon reading this, many of you might think:
"I hardly have enough time to work out when I'm already super-setting exercises. How can I possibly be expected to rest longer between sets?"
There are one of two possibilities:
- Do fewer sets and exercises using heavier weights and longer rest times.
- Use the more extended, three-minute rest intervals on your heavy compound lifts (presses, rows, squats, deadlifts, pull-ups, etc.) and use moderate rest intervals (60 to 90 seconds) between sets of isolation exercises (curls, kickbacks, tricep extensions, laterals, etc.)
Takeaway
In the end, as long as you are training hard, employing the principles of progressive overload, and eating right for your goals, you will get results.
Could your results be potentially better by "optimizing" your rest periods for your style of training...quite possibly. But, you also have to consider how much time you have each day to train and how much volume you need to complete each week to maximize results.
Rest assured, so long as you’re training your muscles to a high level of fatigue, adding reps/weight when possible, eating right, and getting enough sleep, you will get results!
