How Sleep Can Affect Your Fitness Performance

We all know the many physical and health benefits sleep can have on the body, but how about its effects on fitness? Where does sleep tie in there?

As standard we should all aim for 7.5 to 9 hours sleep per/night. However for some that just isn’t possible.

Athletes or those that are more active will need more sleep than normal, the same way you would need more calories when exercising. You’re burning more, therefore you replace more.

During your sleep you are repairing and recovering from any damage caused by stress and exertion built up throughout the day.

The Affects of Sleep Deprivation on Fitness Performance

Reduced energy levels:

If your sleep is suffering then so will your energy levels, which will only increase or worsen if you don’t allow your body the rest it needs.
But why does our energy suffer? One word, glycogen!
Glycogen being glucose from food that is stored in animals and converted to energy when needed goes hand-in-hand with sleep. Therefore not enough sleep will result in less glycogen therefore less energy!.


Sleep deprivation will lead to the release of cortisol on the body, a stress hormone. The increase in cortisol will lead to lower growth hormone levels affecting repair and recovery in the body making you more prone to injury.


All sports require a form of alertness, a lack of sleep will have a play on effect with your ability to make accurate split-second decisions, which can have a serious impact on performance!
Just like your body, your brain needs re-charging also. Don’t run yourself down!

Tips to Improve Quality of Sleep & Fitness Performance

So how can I improve the quality of my sleep!?

A few tips I have learnt and adapted is using an app called F.lux on my Mac. This adjusts the colour of your display according to your location and time of day, replicating the room you’re in. F.lux prevents blue light on your screen which has been shown to have a negative affect on sleep.

Having a warm shower / bath an hour before going to bed. This helps relax the muscles and puts you into a comfortable state, making it easier to sleep and drift off.

Also turning off all screens or devices 30 minutes – 1 hour before sleep and keeping the room dark. Similar to F.lux this will help prevent blue light absorbed helping you to relax.