how rest impacts exercise

How Sleep Affects Working Out – How Rest Impacts Exercise

You’ve probably noticed that a lack of sleep negatively impacts your strength and stamina during exercise. Something else you might have noticed is a lack of sleep impacts recovery, with your body taking longer to heal.

No, you aren’t going mad – the effects are real!

Even if you eat well and don’t overtrain, poor sleep can impact your performance at the gym and stunt your progress. But why?

How does sleep affect working out?

Sleep impacts exercise because sleep is the only time your brain and body recover from the previous day’s activities.

During sleep, your body produces human growth hormone (HGH), which is responsible for growing new tissue in the body. Sleep also releases protein-building amino acids responsible for muscle growth and recovery.

Also Read: How to Recover from an Ankle Injury

The big reason why a lack of sleep impacts working out is that sleep removes toxins from the central nervous system. Strength training is adversely impacted if these toxins are not removed during sleep.

Another way rest impacts exercise is motivation. You are more likely to work out harder and faster when your body is fully energised.


Poor quality sleep impacts exercise performance, and sleep is necessary to heal your muscles and refresh your central nervous system. If you don’t sleep well, you will notice a reduction in performance across all activities.

Cardio and stamina 


sleep deprived runners

Cardio and stamina suffer from a lack of sleep. In this study, sleep-deprived runners ran a lot slower and found it a lot harder than regular runners. A lack of sleep makes you feel tired earlier in exercise and makes it harder to keep going.

Rest and recovery 

A lack of sleep slows down recovery, reducing the number of days you can work out at a high intensity. Because recovery is slower, you are also at a higher risk of injury. Without sleep, your body can’t heal itself.


One of the side effects of poor sleep is a lack of motivation to work out, often because of tiredness and fatigue. Additionally, you are more likely to end sessions early, skip exercises and take additional recovery days.


A lack of sleep makes you more likely to reach for sugary quick-win snacks and drinks that give you lots of energy for a short burst. You are less likely to stick to your diet, reducing your performance during exercise.

How to sleep better to boost your workouts 

boost your workouts

Now you know how important sleep is to exercise, you’re probably wondering what you can do to sleep better. Here are some practical tips:

  • Avoid caffeine six hours before bedtime. This study found that caffeine consumed within six hours of sleep is highly disruptive.
  • Avoid sugary snacks at least two hours before bedtime. Sugary snacks spike blood sugar levels during sleep, which can wake you from a deep sleep.
  • Get a comfortable mattress. A mattress that supports your primary sleeping position (side, front, back) will stop you from tossing and turning.
  • Wind down. Have a bath, turn off the TV, meditate, read a book. Winding down will reduce your stress levels and slow your breathing.
  • Go to bed at the same time every night. This will help you get enough sleep and put you into a routine.
  • Wake up at the same time every morning. This is the best trick in the book to reset your body clock and create a healthy sleep cycle.

Aim for 7-9 hours of sleep per night 

Most adults need between seven and nine hours of sleep per night. Some adults can make do with six hours, but this end of the scale is thin. With 7, 8, or 9 hours of sleep, your body has all the time it needs to stay healthy.

Also Read: Is Indoor Running Good for Toning Legs?

A night of poor sleep will affect your workout the next day, but not in the long term. If you have a long-term sleeping problem, this will impact your health and fitness. Be sure to speak to your GP about any chronic sleep problems.