By Daniel G. Graetzer, Ph.D.
Faculty Member, School of Health Sciences
New Year resolutions for exercising more often and consuming less alcohol are common. Exercising more is the most common New Year’s resolution, with about 50% of Americans initially making this commitment. Unfortunately, relatively few people continue regular exercise more than a few months.
Drinking less alcohol is another common New Year’s resolution. Mild to moderate alcohol consumption has been touted by some individuals as a way to reduce the risk of heart disease, stroke and diabetes. However, medical science shows that alcohol has a definite impact on athletic performance.
The Pros and Cons of Imbibing Alcohol Prior to Athletic Competitions
Some psychological studies have indicated that the moderate consumption of alcohol before an athletic competition may reduce anxiety and enhance relaxation and self-confidence during competition. Larger doses of alcohol may also decrease an athlete’s sensitivity to pain and reduce external visual and auditory distractions.
However, an alcohol-inhibited central nervous system impairs an athlete’s reaction time, hand-eye coordination, accuracy, balance and rhythmic muscular movements. Athletic performance is affected most seriously in those sports that require rapid reactions to changing stimuli, such as soccer, football, basketball, baseball and hockey.
Also, carbohydrate metabolism involving the conversion rate of glycogen stored in the muscles into usable energy is critical during prolonged exercise, and it can be severely inhibited by a high blood alcohol level.
In addition, the hangover after a bout of drinking reduces an athlete’s concentration and mental acuity. The athlete may experience mild withdrawal symptoms, a release of histamines and headaches caused by allergic-type reactions.
More histamine in the body increases blood capillary permeability to white blood cells and some proteins natural from cells in an infected area of the body, enabling them to fight pathogens. When histamine causes blood vessels in the brain to dilate, the pressure increases, which can eventually lead to inflammation and head pain.
The Effect of Alcohol on the Body’s Systems and Athletic Performance
Alcohol is a diuretic that increases urine output and dehydrates the body. For instance, consuming 12 ounces of beer will stimulate your body’s excretory system to urinate and produce about 15 ounces of fluid.
The diuretic effect of alcohol will in turn stimulate thirst after a drinking bout and lead to dehydration. In fact, many alcoholics end up dying from dehydration before alcohol’s other negative effects get to them.
In addition, pre-exercise dehydration as the result of drinking alcohol, combined with the dehydrating effects of sweating during exercise, can critically compromise cardiovascular and respiratory function.
A high blood alcohol level causes the peripheral blood vessels to dilate, resulting in the loss of body heat and a drop in body temperature. Ever wonder why intoxicated spectators in a cold football stadium are always shivering and often do not even notice the cold until mild frostbite sets in? Excess vasodilation disrupts the body’s normal temperature regulation during exercise, which may impair an athlete’s endurance and performance because controlled heat increases are needed to speed up chemical reactions in the muscles.
Chronic, excessive alcohol consumption may also cause a substantial increase in body weight. Ethanol yields slightly over seven raw calories per gram (about one calorie per proof per ounce). Thus, one ounce of 100-proof distilled spirits yields approximately 100 calories, while one 12-ounce beer contains about 135 calories.
The calories from alcohol are considered “empty” calories by nutritionists because they yield nothing more than raw energy and contain no vitamins, minerals, or protein. Since ethanol cannot be stored in body tissues, the body uses these calories for energy before other substrates.
Excess calories such as those calories found in alcohol are converted to fat for storage, causing the beer bellies often seen in weekend athletes. An excess accumulation of body fat diminishes athletic performance because the body must work harder to carry around the additional weight. By restricting how quickly and efficiently the body’s weight can be moved, extra weight decreases an athlete’s running speed, jumping ability, body heat dissipation, and endurance capacity.
Distilled and brewed beverages require no digestion and are quickly absorbed from the stomach and small intestine into the bloodstream. Ethyl alcohol – unlike carbohydrate, fat and protein – is absorbed almost immediately because an ethanol molecule is so small that it does not have to be broken down further to cross over into the circulatory system. Ethanol cannot be stored directly in body tissues and is thus metabolized by the liver.
However, even those most dedicated to “ethanol-conditioning” their livers can only break down a few grams of ethanol per hour, which in turn causes alcohol to accumulate in the blood when it’s consumed at a faster rate than the liver can process it. In addition, consuming alcohol in a high-altitude area, such as in the mountains of Colorado, causes deceptively higher blood alcohol concentrations than at sea level. The lower partial pressure of oxygen at high altitudes reduces the oxygen supply the liver needs for metabolism.
The human body requires a continuous supply of oxygen to maintain its metabolism (the use of substrate to create energy for maintaining life-sustaining biological processes). This oxygen enters the body through the lungs, where it binds with hemoglobin in the bloodstream for transport to the tissues.
A reduced partial pressure of oxygen, however, impairs the oxygenation of blood flowing through the lungs. A bloodstream with a reduced oxygen saturation will consequently deliver a diminished supply of oxygen to body tissues, which in turn affects one’s athletic performance.
Related link: How Nurses Can Cope with the Stress of COVID-19
The Effect of Alcohol on the Brain and Nervous System
The legal intoxication limit varies between U.S. states, but it is most often near 0.08% or 800 milligrams of ethanol per liter of blood. Much of this intoxication affects the highly vascular region of the head, where the drinker’s state of consciousness is altered by depression of the central nervous system through selective receptor sites in the brain.
Ethanol depresses neurotransmitters in the control center of the cerebrum with larger doses spreading back into the cerebellum. The cerebrum is responsible for reasoning, perception, and complicated thought processes, while the cerebellum controls muscle coordination and balance.
Relaxation, blurred vision and impaired neuromuscular coordination result when neurons cannot effectively transmit impulses between the brain and body. Alcohol affects individuals differently due to factors such as:
- Body size
- Alcohol tolerance level
- The drinker’s state of dehydration
- The amount of food in the drinker’s stomach
Alcohol Manufacturers Are Targeting Young Sports Fans
Now, the alcohol industry is targeting young sports enthusiasts. Due to alcohol-fueled incidents in crowd behavior during sports competitions, many athletic governing bodies and professional teams are beginning to curtail the alcohol consumption of their fans. In fact, many major league baseball parks are no longer selling alcohol after the 7th inning.
Ideally, both physical exercise and alcohol consumption should be done in moderation to avoid physical problems. The new year is rapidly approaching with many making initial commitments to health, diet and fitness resolutions.
Success is most often greatest when resolutions are reasonable and done with accountability to others. Best wishes for maintaining your New Year’s resolutions in 2022!