Alcohol (ethanol) is a small molecule that diffuses into the body very quickly, before being transformed (90%) in our liver. This gives him time to act on all organs (brain and heart in particular), tissues and muscles.
Among the causes of muscle cramps, we will retain the metabolic origin: the overproduction of lactic acid, and following the loss of water (dehydration), the loss of metabolites such as sodium or potassium.
The practice of a sports activity can cause cramps because muscle fibers will be destroyed during exercise and lactic acid will be produced in excess. Indeed, the succession of muscle contractions limits blood circulation and the supply of oxygen to the muscles. These continue to use sugar (glucose) to function, through a process of lactic fermentation. This transformation frees up a little energy, without the need for oxygen; but the accumulation of lactic acid induces muscle fatigue which limits the duration of such efforts.
Sweating helps regulate body temperature during physical or sports activity and maintains a constant temperature. Sweat contains water, but also mineral salts like sodium and potassium. These losses are also the cause of muscle cramps.
The effects of acute alcoholism
Alcohol acts on a hormone, the antidiuretic hormone or vasopressin, blocking the reabsorption of water in the kidneys. Thus, alcohol accelerates diuresis, the elimination of urine: the urine is abundant and clear (with beer, for example). You probably have in mind the Munich Oktober Fest, where the beer flows freely and there are more than 900 meters of urinals.
Drinking alcohol does not allow you to hydrate, quite the contrary! This leads to dehydration, a feeling of dry mouth and headache, and can be accompanied by a loss of sodium (especially in heavy beer drinkers), potassium and magnesium. All the ingredients to have muscle cramps. The advice is, therefore, to hydrate yourself well during the evenings when you drink alcohol, alternate consumption of alcohol and soft drinks (water, fruit juice, for example).
In addition, in athletes (endurance sports in particular), alcohol decreases the ability of muscles to use glucose and amino acids, both essential for building new muscle fibers and blood vessels. You will expose yourself to a greatly increased risk of muscle injury. It is therefore advisable not to consume alcohol after training and recovery phases.
It is, therefore, necessary to drink well, but water, not alcohol like beer for example. And attention to energy drinks ( energy drinks ) as Red Bull, which must not be confused with sports drinks ( sports drinks ): their association with alcohol will mask the effects: less fatigue, less feeling dry mouth and less perception of motor coordination disorders.
In addition, avoid energy drinks without sugar during or after an effort: the absence of sugar (glucose) will worsen lactic acidosis and promote the appearance of muscle cramps.
The effects of chronic alcoholism
Regular alcohol consumption can be the cause of the appearance of night cramps: a case-control study conducted by Chloé Delacour and his team with 140 seniors (average age: 68 years) shows that alcohol consumption at least once a week multiplies by 6.5 the risk of having night cramps in the legs.
Ethanol acts on the nerve fibers, at the level of the myelin sheath (fat forming the sheath of nerve cells), and can lead to damage to several nerves, polyneuropathy or polyneuritis, which will affect the 2 lower limbs. This is manifested classically when consumption exceeds 21 glasses of alcohol per week in men, 14 glasses per week in women. These pains are aggravated by cold and humidity and improved by heat.
A deficiency in thiamine (Vitamin B1), a vitamin necessary to transform glucose into energy (in the brain in particular) is often found. This is explained by the nutritional deficiencies observed in the alcohol-dependent person, with a poor diet which leads to a lack of vitamins.
The progressive appearance of muscle cramps that start at the extremities (feeling of having cold feet) and then go up to the calves is classic. Stopping alcohol consumption associated with taking vitamin B1 can gradually reduce this nerve damage.
In conclusion, alcohol can, therefore, be responsible for muscle cramps, or even worsen them, during acute or chronic alcoholizations. Rehydrating yourself well with non-alcoholic drinks (still water, sparkling water) will prevent muscle cramps from occurring.