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The Science of Muscle Recovery (How Long to Rest Between Sets)

Intra-workout recovery is a hot topic these days, and most athletes want to know how long they should rest between sets based on their goals.

Let’s see what research has to say on the topic and what that means in a practical sense.

How Long Should You Rest Between Sets?

There isn’t a single answer to the question, “How long should I rest between sets?” 

Athletes differ in body composition, fitness level, and training experience, so there isn’t a single ideal recommendation. Inter-set rest periods shown in scientific articles are based on general recommendations for the average person.

The ideal recovery period can vary from one athlete to the next and will depend on various things, which we will explore below. Each athlete should be aware of their recoverability and strive to optimize their recovery periods instead of taking general recommendations and running with them.

Differences in the ideal recovery period vary even more among part-time athletes, who often have unique life situations, follow different schedules, and have unique limits for how long they can train each week.

For example, if one person has more free time to spend at the gym, their inter-set rest time can be longer to ensure the best possible performance and safety. In contrast, a person with less time for working out will have to shorten their rest periods, which the Strongineering framework can optimize.

There is another factor that isn’t discussed nearly as much as it should be. On top of generalized recommendations, how long a person chooses to rest between sets should depend on:

 

  • How challenging the exercise is
  • How much weight the trainee lifts (and what repetition range they use)

For instance, the seated dumbbell shoulder press and conventional deadlift are compound exercises. Therefore, a coach might provide a general recommendation of resting for two to three minutes between sets.

Unfortunately, that approach is too generalized. First, deadlifts are a full-body exercise that leads to much more fatigue than a seated shoulder press. Second, the load used during a set matters. People generally use more weight for deadlifts than shoulder presses and need longer rest periods to maintain good performance.

Paying attention to such details is particularly important when athletes do strength and peaking phases, where most sets are heavy and close to muscle failure. Longer rest periods would allow for better recovery and performance.

What Does Research Say About Rest Periods?

Research notes that rest periods are an essential training variable that affects short-term training performance, how a trainee’s body responds to an exercise bout, and the results they can achieve. 

In one review from 2009, researchers looked at 35 studies that examined the short-term response and chronic adaptations in relation to different inter-set recovery periods. The objective was to understand how rest periods affect specific adaptations (strength, endurance, hypertrophy, etc.).

One of the key findings related to the acute response to training. Longer rest periods (3 to 5 minutes) allowed for more reps when subjects in the studies lifted weights between 50 and 90 percent of their 1 RM. 

Additionally, longer rest periods were associated with better strength adaptations, which makes sense. Heavy weight training is necessary for creating mechanical tension and promoting neuromuscular adaptations. Unfortunately, heavy sets are pretty taxing and often leave trainees feeling weak and out of breath for several minutes.

Allowing athletes to rest longer between such disruptive sets would enable them to do more reps, maintain better technique, and cause a stronger training stimulus.

Similarly, training volume, the amount of work trainees do, is crucial for hypertrophy. Allowing athletes to recover longer would help them perform better, accumulate more volume, and grow more effectively.

A 2016 paper by Brad Schoenfeld and colleagues further suggests these effects to be true. In it, researchers compared shorter and longer rest periods and their impact on muscle adaptations in young, experienced lifters.

The participants were split into two groups, resting for 1 or 3 minutes between sets. All other training variables were held constant. The study lasted 8 weeks, and subjects performed three full-body workouts each week with 7 exercises per session.

Muscle thickness and strength were significantly greater in the group resting for three minutes between sets. Interestingly, short and long rest periods resulted in similar improvements in muscle endurance. Logic would suggest that shorter rest periods would impact cardiovascular capacity more, but that didn’t appear to be the case in this study.

Why You Should Rest More On Heavy Compound Lifts?

Most of us lead busy lives and cannot spend too much time at the gym, which is one reason why shorter rest periods are so appealing. But if you’ve read everything so far, you understand how important recovery is for your safety and long-term progression.

Every athlete should prioritize safety and carry the mindset of minimizing training risks, regardless of goals, fitness experience, or training preferences. Staying injury-free allows athletes to train more often, which provides more opportunities to cause a stimulus and see improvements.

Longer breaks between sets allow your body to recover, leading to better performance, good technique, and a lower risk of using compensatory tactics (e.g., momentum, swinging your body, etc.) to maintain your performance.

In addition, research suggests that longer rest periods lead to greater strength adaptations, which makes sense. Heavy training is necessary for strength development, and longer breaks allow trainees to maintain proper form and do more stimulative sets and reps.

Longer rest periods are particularly important for high-intensity sets, especially those where athletes train to an RPE of 9-10 or to muscle failure. Pushing yourself to your limit is quite taxing on the body and mind, and longer rest periods are crucial for good performance. 

Rushing the recovery process would often result in a significant reduction in performance or the use of compensatory tactics to complete the same number of reps as before.

What Research Says About Rest Periods For Accessory/Isolation Exercises?

So far, we’ve primarily examined the impact of training effort and intensity (percentage of 1RM) and the impact on recovery needs. But the exercise itself is another factor that influences how long you should rest.

Research suggests that longer rest periods are still superior to hypertrophy, even for accessory and isolation exercises. While the fatigue might not be as high, longer rest periods result in:

  • More repetitions per set
  • Better technique
  • Improved mind-muscle connection
  • More enjoyable workouts

For example, if a trainee rests longer between sets, they wouldn’t get as tired, allowing them to stay more motivated and push themselves hard. In addition, they would be able to maintain proper technique, target the correct muscles, and experience better results.

In one 2009 study, researchers took 12 untrained subjects and put them on a 10-week training program. One group rested for a minute between sets, whereas the other rested for 2.5 minutes. 

The participants did several isolation exercises (leg extensions, lateral raises, ab crunches, etc.) and took all their sets to failure or close to failure.

Once the experiment was over, researchers measured the arm and thigh cross-sectional area in the 12 subjects and noticed significantly greater improvements in the group resting for 2.5 minutes between sets.

The study implies that longer rest periods are necessary for optimizing training results.

Can Shorter Rest Periods Be Used In Some Cases?

The above sounds great, but what if you simply don’t have the time to rest for two or more minutes between every set? For example, if your average workout has 18 sets, that would mean resting for at least 36 minutes. Add a warm-up, the actual training, and a brief cooldown period, and you’re easily looking at a 70+ minute workout.

The good news is that athletes can afford to take shorter breaks on accessory and isolation exercises when facing time constraints. 

For instance, some research suggests that shorter rest periods (as little as 30 to 60 seconds) in combination with drop sets can cause greater temporary anabolic hormone increases. 

In one 2009 study, researchers examined three rest periods (60, 90, and 120 seconds) and their impact on growth hormone and testosterone levels. Blood was drawn before, immediately after, and 30 minutes after exercise.

The researchers noted significantly higher serum growth hormone concentrations in subjects resting for 60 seconds compared to 120 seconds. We still need research to fully understand the impact of anabolic hormone spikes on hypertrophy and strength outcomes, but these findings hint at the value of shorter rest periods.

We have another recent study to muddy the waters even further. Researchers put nine men in one of three groups:

  • 3 sets of failure with 80 percent of 1 RM – 3 minutes of rest
  • 3 sets of failure with 30 percent of 1 RM – 1.5 minutes of rest
  • Drop set condition where athletes take all sets to failure, going from 80 to 30 percent of 1 RM over 5 sets

All subjects did the single-arm dumbbell bicep curl two to three times per week for two months. 

Once the experiment was over, researchers measured bicep growth and concluded that the subjects across all three conditions saw similar growth. In other words, three minutes between sets didn’t result in more growth than 1.5 minutes. Perhaps more shocking is that not getting any rest (the drop set condition) resulted in the same hypertrophy.

One potential explanation is that athletes don’t need more than 1.5 minutes between rest on isolation exercises to maintain their performance. This would explain the similar results between the 3 and 1.5-minute groups.

As far as the drop set condition goes, the subjects didn’t get any rest but performed two more sets in every session. As we know, training volume is tightly related to muscle growth, so that could be the reason for the results.

The Strongineering Framework would reduce the inter-set rest periods if an athlete has less time to work out on a particular day. This is especially true for the accessory exercises. 

Why Athletes Need Flexible Resting Periods?

It would be great if cookie-cutter rest period recommendations worked equally well for everyone, but that isn’t the case. As you can see, numerous factors impact a person’s recovery needs, which means rest periods need to be individualized like everything else.

First, we must get clear on what proper recovery means. Rest periods allow athletes to dissipate some of the fatigue, maintain good performance, and perform each repetition with proper form. Doing so reduces the injury risk and allows athletes to experience the best possible training stimulus.

Rest periods should be customized based on RPE, heart rate, and self-athlete measure reports. 

In doing so, the Strongineering framework ensures that the athlete’s cardiovascular system has recovered adequately. With a normal heart rate, the athlete can focus on the technical execution of each exercise while keeping the risk of light-headedness or dizziness at bay.

In some cases, rest periods might vary between sessions under identical conditions because of external factors like sleep quality, life stress, nutrition, hydration, and more.

Final Words

Inter-set rest intervals are crucial in athletes’ ability to train hard and make optimal progress. Too many trainees shoot themselves in the foot by rushing through their workouts because they fall for outdated ideas or simply don’t have enough time to rest. 

In addition to improving the technical execution of movements and allowing trainees to do more quality reps and sets, we could also argue in favor of maximum recoverable volume (MRV).

We don’t have hard data to back the idea up, but it makes sense. Longer rest periods allow athletes to train harder, do more reps and sets, and maintain proper technique, which are all components of MRV. 

If an athlete rests longer, they will likely be able to do more sets, recover adequately, and see better results in the long run. Similarly, managing effort levels by training within an RPE of 7 to 9 can also positively impact MRV. The occasional set to failure can be helpful, but if athletes push themselves to their limits all the time, they can quickly run into overtraining issues.

Of course, there is a limit to how much productive work a person can do before they run into overtraining issues. The Strongineering framework can provide practical recommendations for optimizing your training volume based on goals, schedule, experience, and more.