How can alcohol affect exercise?

I am sure that we have all had those times when our good intentions of completing an exercise session have been slightly derailed by getting invited to go for a drink on the day before.

Of course, one drink turns into two and it would be rude not to have one more, so before you know it you are climbing on your bike or setting off for a run feeling a little worse for wear.

Whilst many of us will find the iron will to power through, we definitely will not perform at the peak of our ability.

So, what is it that alcohol is actually doing to our body that makes exercising feel so difficult?


Alcohol is a diuretic, meaning that it causes our kidneys to produce more urine. When the amount of water in our body drops, so does the volume of our blood. This means that there is simply less blood to carry oxygen, energy, and nutrients to our working muscles.


Alcohol is treated by your body as a toxin, so after you have had a few drinks, your liver goes into overdrive to clear out what it deems as harmful. When the liver is clearing out alcohol, all other functions are slowed down, including glucose production. This means that the energy supply to your muscles is also slowed down.


If your liver is still clearing out the toxins from alcohol, it is slower to break down the lactic acid released through exercise, making you more likely to suffer from muscle cramps.

Nervous system 

Alcohol suppresses the activity of the central nervous system. This means that the signals which are sent to your muscles to contract are simply not as strong.Which make it feel like you are working harder to do the same exercise.

Heart function

Alcohol is known to increase the risk of heart arrhythmias, unusual heart patterns, up to two days after heavy drinking.

Drinking after exercise:

Sleep patterns

Alcohol is known to disrupt sleep patterns, an important time for our body to recover and produce many hormones. Heavy drinking after exercise is therefore thought to reduce the muscle’s ability to grow and repair.


Drinking alcohol stops you from absorbing the precious water that your body needs to recover.

So, when it comes to drinking and exercise, the results are not good.

Of course, a few drinks in moderation is not the end of the world.

But it might be a good idea to avoid any heavy drinking the day before an exercise session, otherwise you will be making life more difficult for yourself and your body will most definitely feel the effects.

Hope this sheds a little light on this area for you!