Alcohol and Running: How Does a Glass of Wine or Beer Affect Your Training?

What does alcohol do in your body after exercise?

Alcohol is a toxin that your body prioritizes over all other processes. As soon as you drink, your liver focuses on breaking down alcohol. Everything that normally runs simultaneously (fat metabolism, protein build-up, glycogen replenishment) slows down.

For runners, these are three processes that you would rather not slow down after training.

Muscle recovery

Alcohol inhibits protein synthesis: the process by which your muscles repair damaged tissue and become stronger. A study published in PLOS ONE showed that alcohol intake after exercise can reduce muscle protein synthesis by up to 37%, even if proteins were consumed at the same time.

That effect is strongest in the first 8 hours after an intensive training. Anyone who drinks heavy amounts immediately after heavy interval training or a long endurance run undermines the recovery process.

Glycogen fill

Alcohol disrupts glycogen synthesis: the replenishment of carbohydrate reserves in your muscles. Anyone who drinks after an exhausting workout instead of taking carbohydrate-rich recovery food will start the next workout with poorer fuel supplies.

Moisture balance

Alcohol suppresses the antidiuretic hormone (ADH), causing your kidneys to produce more urine than normal. You pee more than you drink. After a workout where you have already lost fluid, alcohol further increases dehydration. You can read more about hydration on the hydration page.

The effect on sleep

This is perhaps the most underestimated effect of alcohol on sports performance. Alcohol does indeed help you fall asleep faster, but it significantly disrupts sleep quality:

• REM sleep (the recovery phase for cognitive functions) is suppressed
• Deep sleep (phase 3, where growth hormone is secreted for muscle repair) is disturbed in the second half of the night
• You sleep more restlessly and wake up more often

Growth hormone is essential for muscle recovery and is largely secreted during deep sleep. Anyone who drinks sleeps worse and therefore recovers less efficiently, even if he or she has been in bed for enough hours.

The effect on sleep already occurs with moderate use: even 1 à 2 glasses can measurably disrupt sleep architecture.

What is the impact on your running performance?

With moderate use (1à 2 glasses, not the night before a race), the direct effect on your running performance is limited. Your VO2max, running economy and lactate threshold are not significantly affected by social alcohol consumption.

The problem lies rather in the indirect effects:

• Poor sleep the night before a training or match
• Dehydration at the start
• Reduced recovery from the previous training
• Slight increase in heart rate with equal exertion (the day after drinking)

With larger amounts, the effects are more immediate: coordination, reaction time and thermal regulation are affected, all relevant while walking.

The day after a party: what can you expect?

A hangover is essentially a combination of dehydration, electrolyte loss, lack of sleep and the effects of acetaldehyde (the breakdown substance of alcohol) in your blood. While walking, that translates to:

• A higher heart rate at the same pace
• Fatigue faster
• Reduced coordination and concentration
• A higher perceived exertion

Running with a hangover is not dangerous for healthy athletes, but it is a tough workout. Whether you do that is up to you. A gentle recovery run of 30 minutes can even support the recovery process through increased blood flow, but intensive sessions are of little use the day after heavy drinking.

Practical: when is it less serious?

Not all moments are equal. When alcohol has less impact:

Not immediately after an intensive training: the first 4 à 8 hours after a hard session are the most critical recovery window. Avoid drinking during that period if you have quality training the next day.

On the weekend, not for a weekly training: runners who start on Monday with an interval or tempo run pay for the weekend. Those who take it easier during the week and leave more room at the weekend will experience less impact.

Not the night before a race: this sounds obvious, but one or two drinks the night before a race also disrupts sleep and starts the morning of the race with mild dehydration.

Frequently asked questions

In summary

Alcohol slows muscle recovery, disrupts sleep, increases dehydration and reduces glycogen refill. Moderate use at the right times (not immediately after intensive training, not the evening before quality sessions or competitions) has limited influence on your long-term running performance. But if you want to recover optimally, choose water and food over alcohol after heavy training.

→ You can read everything about recovery nutrition after running on the page nutrition after running.
→ Back to the nutrition overview for runners.