Studies show that there's nothing wrong with moderate alcohol consumption, at least from a health standpoint. In fact, certain types of alcoholic beverages have been shown to have health benefits when enjoyed in moderation, such as a glass of red wine that contains heart-healthy resveratrol, or a dark beer that contains cancer-fighting polyphenols.
That said, alcohol, even in moderation, may not be terribly beneficial to runners when it comes to their performance on the track, so to speak. Alcohol and exercise have never been a great combination for a number of reasons. Because running already puts so much strain on the body, the additional stresses of liquor on the system could be exacerbated.
There are certainly runners, and successful competitors at that, who claim that a little alcohol the night before a big race is beneficial because it calms the nerves and aids in slumber (as opposed to a night of restless sleep brought on by anxiety over the impending challenge). Others like to knock back a few celebratory cocktails following a particularly stressful race.
In both cases, the effects of alcohol could actually be detrimental to both health and performance. Here are just a few ways in which alcohol consumption can affect a runner's performance.
Drinking Prior to Running
Anyone who has tied one on while out with friends knows that the next day is going to be a doozy, complete with fatigue and perhaps a headache or nausea - the classic signs of a hangover. Even though alcohol is a depressant, it tends to impair sleep function, resulting in reduced restfulness and poor performance.
Of course, most runners aren't doing keg stands the night before a race. That said, even a couple of drinks meant to relax you could be enough to leave you suffering from grogginess and reduced energy the following day. In other words, there are probably better ways to reduce your anxiety and get a good night's sleep before a race.
As a runner it is important to properly hydrate before, during, and after a race. Dehydration can cause headaches, nausea, cramping, fatigue, and even more serious issues for athletes. As you may or may not know, alcohol is a diuretic, meaning it causes your body to purge fluids. This ultimately leaves you uncomfortable and unable to perform at your peak.
Not only does alcohol bring on hypoglycemia that can leave you feeling fatigued, but it can also deplete necessary minerals like calcium and magnesium (thanks to its diuretic effects). Calcium primarily contributes to bone health, but magnesium has a secondary, yet no less essential function.
Magnesium is involved in the process of producing adenosine triphosphate (ATP), which is ostensibly how our bodies create energy. A lack of magnesium needed to facilitate ATP production could result in fatigue and muscle cramps. Over time, you could experience even more severe symptoms like heart arrhythmia, just for example.
Metabolism is a series of chemical reactions that break down molecules to obtain energy and then allow the body to synthesize new substances that are used to sustain life. It's a fairly involved process, but most people understand it to include providing the body with nutrients that are going to produce energy and repair the body.
Alcohol inhibits metabolism in a number of ways. The main problem is that it impedes the body from absorbing and breaking down key nutrients like certain vitamins and minerals. This happens because alcohol affects the liver, which is responsible for certain aspects of metabolizing food and storing nutrients.
What does this mean for runners? It can lead to reduced energy in the short-term and issues like malnutrition in the long term. Because alcohol has so many calories, it could also result in weight gain over time for those who drink in excess.
Drinking after Running
You now have a pretty good idea of how drinking before running can impair performance, but what will happen when you decide to have a few glasses of champagne or a couple of beers in celebration following a race? As noted above, alcohol causes dehydration and impedes the uptake of nutrients the body needs to recover.
The result will be slower healing time, including soreness, stiffness, muscle aches, and fatigue for one or more days. In fact, consuming alcohol after running could mean it takes twice as long to recover, according to some studies.
Alcohol is also a blood vessel dilator, which means slower blood flow to muscles in need of repair following the stresses of a race. This could exacerbate or even lead to injury, or at least slow the healing process.