We spend approximately ⅓ of our lives asleep — but what actually happens during sleep, and why is it needed for exercise recovery?

From a young age, we’re told the importance of a good night’s rest. And while most of us typically get anywhere from 7 to 9 hours of sleep each night, many of us don’t know just how important sleep is.

Chances are, you’ve had your fair share of nights where you just couldn’t sleep. The next day, you feel restless, struggle to concentrate, skip training, and reach for fast food instead of cooking a meal at home.

Sleep and exercise recovery go hand in hand — if you don’t get enough sleep, you’ll likely see a decline in training and recovery performance.

Whether you’re into endurance sports such as cycling, running, or ultrarunning, or you just enjoy lifting weights a few times a week, you need enough quality sleep each night. 

Why is sleep important?

According to the CDC, 1 in 3 adults do not get enough sleep.

But sleep is important for virtually all bodily functions — if you don’t get the recommended amount, you’ll soon begin to experience the side effects.

To better explain how sleep works, we need to break down the 4 sleep stages:

  1. Awake — time spent before falling asleep and time spent in bed.
  2. Light sleep — your muscles relax, heart rate decreases, and body temperature drops.
  3. Deep sleep — growth hormone is released, energy stores replenished, and memories are processed.
  4. Rapid eye movement (REM) sleep — known for its vivid dreams, REM sleep focuses on memory, learning, and problem-solving.

It takes approximately 90 minutes to complete a full sleep cycle — that includes stages 1 to 4. During the night, you’ll typically repeat the cycle 4 to 6 times.

Repeating these cycles is important for rest and recovery, including everything from processing memories to repairing muscle tissue.

The relationship between sleep and exercise recovery

All sleep stages play an important role in the body, but deep sleep is especially crucial for athletes. 

During deep sleep, growth hormone is released — this repairs damaged muscle tissue. Also, the body replenishes energy stores and sends oxygen and nutrients to the muscles and body to regenerate cells.

If you don’t get enough sleep, you’re more likely to feel fatigued and sore the day after a workout. 

Similarly, not sleeping enough may lead to cognitive decline. That could mean lapses in concentration and memory, losing your train of thought, or finding it hard to make decisions.

What happens if you don’t get enough sleep?

The big question: what happens if you don’t get enough shut-eye?
Research shows a short-term lack of sleep results in:

  • Stress
  • Pain
  • Depression and anxiety
  • Cognition and memory issues
  • Poor performance
  • Inadequate recovery between workouts

Long-term effects of disrupted sleep are typically more severe and include weight gain, metabolic syndrome, and others.

What are the best ways to improve sleep quality?

If you’re putting in plenty of miles on the bike and a few strength training sessions a week, you’ll know just how important sleep is.

Firstly, you may find yourself wanting to sleep more, perhaps feeling more lethargic than usual. Oh, and you’ve probably indulged in 1 or 2 midday naps — they’re great, right?

But to get the most out of your training, whether running, cycling, weight lifting, or any other workout, you need to get on top of your sleep — that means getting enough quality sleep as often as you can.

To help you get better quality shut-eye, we’ve prepared a few basic tips to help you below:

  1. Wake up and go to bed at the same time every day
  2. Increase light exposure in the early part of the day (and limit exposure in the evening)
  3. Avoid drinking caffeine too late in the day
  4. Set a bedtime routine 
  5. Do not use your smartphone in the bedroom


Can taking sports supplements or other products help me sleep better?

This is a tricky topic — there are sleep supplements, but it’s always recommended to improve your sleep hygiene before experimenting with supplements. If you do want to try sleep supplements, we’d always suggest consulting with a doctor beforehand. 

Does sleep help recover from exercise?

Yes! Growth hormone is released during sleep, which repairs the muscles and cells. Blood is also sent to the muscles, packed full of oxygen and essential nutrients to support recovery.

How does sleep relate to fitness?

Sleep allows the muscles and energy stores to replenish. This stimulates muscle and cell growth and allows you to improve your fitness.

''Research shows a short-term lack of sleep results in:''https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5449130/