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Why Sleep is Critical for Muscle Growth


calendar-iconApril 10, 2021

Build Muscle


Heads up! This article is connected to our Muscle Growth Journey page. For the complete picture on how to build muscle using our evidence-based system, check it out here!

Proper sleep is just as critical as training or nutrition when it comes to building muscle, perhaps even more critical!

In this article, we’ll tell you exactly what you need to do to get the most out of your sleep, and walk you through 5 reasons why sleep is critical for muscle growth, all supported by evidence based research. 

By the end of this article, it should be clear to you why you should prioritize your sleep schedule if you are serious about growing as much muscle as possible.

How to Get Optimal Sleep

First, we’ll cut to the chase and tell you exactly what makes up a perfect night’s rest. We break it all down in more detail in our Basics of Sleep article, but we’ll quickly summarize what you need to know here:

  • You’ll need about 8 hours of sleep a night. You may need a bit more or a bit less, but the goal should be to get enough sleep that you are able to wake up without an alarm and not feel drowsy at any point during the day.
  • Go to bed at the same time every night. Your sleep will be higher quality if you are asleep at a consistent time day in and day out.
  • Make sure your sleep is uninterrupted. Continuous sleep is the best kind of sleep, and ensures your body gets the most out of it’s time to recover.

If you follow those simple rules, you will provide your body with the exact amount and kind of sleep that will boost muscle growth. 

5 Ways that Sleep Boosts Muscle Growth

So, how exactly does sleep boost muscle growth? We’ll walk you through 5 ways in this next section, backed by evidence based research. 

Studies clearly show that optimizing sleep has multiple benefits when it comes to muscle growth!

Sleep prevents muscle breakdown

Folks that do not get enough sleep end up losing muscle. Sleep deprivation has been shown to increase the activity of biological pathways such as cortisol ("the stress hormone") that lead to muscle breakdown.

In other words, by sleeping more your muscles maintain their size and strength.

Your muscles grow during sleep

Studies have shown that certain stages of sleep promote the release of hormones, such as growth hormone; these are responsible for building muscle.

If you don't get a good night's sleep, your body does not hit every sleep cycle, and when that happens, then your muscles miss a valuable opportunity for growth.

Sleep helps your body perform athletically for longer periods

Sleep is critical for having enough energy to crush your workout. 

On the flip side, not getting enough sleep means that your body is not as efficient at converting food into energy, therefore you will get tired sooner. 

Multiple studies have shown that sleep deprivation in athletes reduces glucose metabolism (the conversion of sugars into fuel for muscles) by as much as 40%, causing exhaustion 20% sooner!

More sleep helps workouts feel easier

Every workout involves not only overcoming physical limits but mental limits as well. 

Believe it or not, sleep plays a big factor in your perception of how tired you are, or your rate of perceived exertion. 

In other words, not getting enough sleep will make you think your body is more tired than it actually is, and your workouts will pay the price! Of course, if your workout quality goes down, so will your rate of muscle growth.

Your muscles are stronger after a good night's rest

Research has also shown that sleeping a full night not only helps your muscles get stronger and grow bigger, but it also helps them be stronger during the day. 

If you were to lift weights 3 different days, one day after sleeping poorly, another day after getting a mediocre night of sleep, and lastly on a day after a very restful night, you will find that you can lift the most weight the day that you slept the most. Sleep deprivation actually prevents your muscles from operating at their best.


That wraps up our guide for why sleep is critical for muscle growth! We covered:

  • A consistent sleep schedule that provides around 8 hours of uninterrupted sleep is all you need to get all of sleep’s benefits concerning muscle growth.
  • Sleep is critical to the muscle growth process in multiple ways:
    • Sleep prevents muscle breakdown.
    • Your muscles grow while you sleep, so sleeping more leads to greater muscle growth.
    • Sleep is critical for peak athletic performance and efficiency.
    • Well rested people will find their workouts to be easier.
    • Your strength is boosted if you are caught up on sleep.

Knowing all of this, you should have plenty of reasons to prioritize getting a good night’s rest. If you want to reach your muscle growth as quickly and painlessly as possible, sleep is a critical component.

For the next step in your muscle growth journey, be sure to visit our Muscle Growth Journey page!

References and Useful Research

  1. Dattilo M, Antunes HK, Medeiros A, et al. Sleep and muscle recovery: endocrinological and molecular basis for a new and promising hypothesis. Med Hypotheses. 2011;77(2):220-2. Link
  2. Vanhelder T, Radomski MW. Sleep deprivation and the effect on exercise performance. Sports Med. 1989;7(4):235-47. Link
  3. Myles WS. Sleep deprivation, physical fatigue, and the perception of exercise intensity. Med Sci Sports Exerc. 1985;17(5):580-4. Link
  4. Chen Y, Cui Y, Chen S, Wu Z. Relationship between sleep and muscle strength among Chinese university students: a cross-sectional study. J Musculoskelet Neuronal Interact. 2017;17(4):327-333. Link
  5. Reilly T, Piercy M. The effect of partial sleep deprivation on weight-lifting performance. Ergonomics. 1994;37(1):107-15 Link
Date Created: April 10, 2021

Last Updated: July 12, 2021

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