The Relationship Between Rest and Muscle Growth

5th March 2020
Resting is fundamental for the recovery of your muscles. In this article we’ll look at the relationship between rest and muscle growth.

Physical exercise and sport generate adaptations of many parts of the body. The body adapts to a progressively more intense load through both hypertrophy and muscular growth. This is how it achieves the same or better performance while reducing the perception of the load over your muscles, joints, and bones, and this is how rest and muscle growth are related.

However, in order for hypertrophy to properly kick in, you need to make sure you’re eating a healthy diet and resting enough. Even though you never give rest the importance it deserves, we’ll talk today about why it’s so important.

Rest and Working Out

Rest is a period of inactivity in which the body is relaxed. It recovers the strength that you exerted during the workout session. Rest isn’t just about the time you’re asleep; it’s also any time that you’re not actively exercising.

Knowing how to do this is necessary so that your body can repair any damages done during your training session. Let’s look at some key points about the importance of resting correctly when you habitually exercise.

Long-lasting and quality sleep

Following an appropriate sleep routine is very important for recovering correctly from physical exercise. Depending on your age, your metabolism, and your cerebral physiology, you need either more or less sleep.

In spite of this, experts recommend never sleeping less than seven hours every 24-hour period. You should rest somewhere between 7 and 10 hours a night. Logically, if you do more exercise, you’ll need more downtime, too.

During sleep, the nervous system takes a break from your daily routine, and all that neuromuscular fatigue that you generated during your workout is compensated for. In addition to this, your body secretes important hormones such as testosterone and growth hormone, related to the repair and growth of muscles.

A woman resting in bed.

Discharge phase: rest and muscle growth

Most fitness experts and athletes, especially in strength training, probably know about this concept already. It’s that time when the body recognizes that it has to rest.

That moment in which your performance gradually declines and you feel more tired is the moment to go through a discharge phase. It consists of a period of time, usually between three and seven days in which you barely do any exercise or you do it with lighter intensity than usual.

By overcompensating, you’re able to make it so that the week after your muscles are rested and ready to take on even more challenges than they were before. This strategy is especially useful in anaerobic sports, such as strength training or track and field.

Active rest

This is another way to rest and go through a discharge phase. A period of active rest is when you do less than usual, but you don’t stop exercising.

You could also consider a time when you do some other type of activity as active rest. For example, if you normally do sprints, you can discharge your muscles by going out for a longer and slower run.

A woman running outside.

Rest and muscle growth

Rest, because of the mechanisms that we’ve explained here, makes your muscles grow. Actually, the idea that muscles grow during training is wrong. Really, it happens when you rest.

After your work out, the muscle fibers are damaged because of the exertion you gave. This can produce micro-ruptures in the muscle fibers which is what makes you feel sore. With a healthy diet, however, the body repairs those micro-injuries during the night.

And as we explained before, deep sleep is one of those stimulants that produce a higher secretion of growth hormones. Thanks to that hormone, your muscles will grow and repair themselves while you sleep.

  • Kitamura S, Katayose Y, Nakazaki K, Motomura Y, Oba K, Katsunuma R, et al. Estimating individual optimal sleep duration and potential sleep debt. Sci Rep [Internet]. 2016 [cited 2019 Sep 16];6:35812. Available from: http://www.ncbi.nlm.nih.gov/pubmed/27775095
  • Chaput J-P, Dutil C, Sampasa-Kanyinga H. Sleeping hours: what is the ideal number and how does age impact this? Nat Sci Sleep [Internet]. 2018 [cited 2019 Sep 16];10:421–30. Available from: http://www.ncbi.nlm.nih.gov/pubmed/30568521
  • Dolezal BA, Neufeld E V, Boland DM, Martin JL, Cooper CB. Interrelationship between Sleep and Exercise: A Systematic Review. Adv Prev Med [Internet]. 2017 [cited 2019 Sep 16];2017:1364387. Available from: http://www.ncbi.nlm.nih.gov/pubmed/28458924