Stella Lucia Volpe, Ph.D., R.D., L.D.N., FACSM, is a faculty member in the Division of Biobehavioral and Health Sciences at the University of Pennsylvania, Philadelphia. Her degrees are in both Nutrition and Exercise Physiology; she also is ACSM Exercise Specialist® certified and a registered dietitian. Dr. Volpe's research focuses on obesity and diabetes prevention using traditional interventions, mineral supplementation, and more recently, by altering the environment to result in greater physical activity and healthy eating. Dr. Volpe is an associate editor of ACSM's Health & Fitness Journal®.
Alcohol seems to be a taboo subject to discuss when it comes to athletic performance. Alcohol and athletes have been associated for hundreds of years, and alcohol-associated problems are more widespread in the athletic population because of a perceived adventuresome mind-set among athletes (6). Alcohol use and abuse result in negative effects on health and athletic performance (6,7). This Nutritionist's View column focuses on how alcohol consumption can impair athletic performance.
DEFINITION OF ALCOHOL
According to Wikipedia, ethanol (also called ethyl alcohol, pure alcohol, grain alcohol, or drinking alcohol is a "volatile, flammable, colorless liquid." It is one of the oldest recreational drugs and is considered a potent psychoactive drug. The molecular formula of ethanol is C2H5OH (http://en.wikipedia.org/wiki/Ethanol).
ACUTE AND CHRONIC EFFECTS OF ALCOHOL CONSUMPTION
Although it has been well established that, for example, red wine has strong antioxidant effects that can help prevent cardiovascular disease when consumed in moderation, chronic heavy alcohol use is related to a number of physiological and social negative outcomes. Alcohol abuse has been estimated to cause 100,000 deaths per year in the United States (2-4,8); http://www.uhs.uga.edu/aod/athletic-performance.html).
The acute effects of alcohol consumption will lead to impairments in motor skills and physical performance, which will most certainly lead to a diminished athletic performance. Table 1 provides a more comprehensive list of acute effects of alcohol on athletic performance.
The long-term effects of alcohol abuse can lead to muscle damage and muscle weakness, which also would directly lead to impaired athletic performance.
Although Shirreffs and Maughan (7) reported that strength is modestly affected by alcohol use, they also stated that performance impairments depend on the dose and habituation to alcohol intake, exercise duration, environmental circumstances, and other issues. Chronic alcohol consumption also has been associated with exercise-induced anaphylaxis and asthma (2-4,8); http://www.uhs.uga.edu/aod/athletic-performance.html).
Alcohol affects each organ in the body and is related to a number of diseases. Heavy chronic alcohol consumption can impair athletic performance by a number of mechanisms, which include: 1) altering the cardiovascular, metabolic, thermoregulatory and neuromuscular response to exercise; 2) causing nutritional deficiencies caused by either decreased nutritional intake or as a result of alterations to digestion, absorption, metabolism, and excretion of nutrients; 3) myopathy (disease of the muscle [skeletal and heart], resulting in wasting and weakness); 4) decreasing testosterone production in men, leading to decreased ability to increase muscle mass and strength; and 5) impairing the central nervous system, resulting in negative effects in cognitive function and motor skill. In addition to these chronic effects of alcohol, women who overconsume alcohol have particular concerns. For example, women's muscular strength is negatively associated with her lifetime total dose of alcohol consumption. In addition, women may be more sensitive to the toxic effects of alcohol on the heart compared with men (2-4,6,8); http://www.uhs.uga.edu/aod/athletic-performance.html).
Another point to stress is that athletes are not protected from the possible severe negative consequences of chronic alcohol abuse that occur later in life, such as liver disease (cirrhosis), endocrine dysfunction, decreased serum testosterone concentrations, seizures, changes in lipid metabolism (leading to elevated lipid levels), ulcers, cardiovascular disease, diabetes mellitus, and bone disorders (http://www.uhs.uga.edu/aod/athletic-performance.html).
ALCOHOL AND SPORTS-RELATED INJURIES
Alcohol use can cause sports-related injuries because of the reduction in cognitive function, balance, and motor control. Alcohol consumption resulted in an injury incidence of 54.8% in athletes who consumed alcohol compared with 23.5% in athletes who were nondrinkers (P < 0.005) (6). Injuries could be related to the hangover effect. Hangovers have been reported to decrease athletic performance by 11.4% (6). It also has been reported that regular alcohol consumption will depress immune function, slowing down the rate of healing from sports-related injuries (2-4,8).
ALCOHOL CONSUMPTION AMONG COLLEGE ATHLETES
Alcohol consumption among athletes tends to be higher than among nonathletes, and this is especially prevalent among the college population. Nelson and Wechsler (5) evaluated college athletes' drinking habits via a nationally representative sample of 4-year colleges in the United States. They found that athletes reported more binge drinking, heavier alcohol use, and a greater number of drinking-related harms than college students who were not athletes. They also reported that athletes demonstrated stronger social ties related to binge drinking than their nonathlete counterparts. Nelson and Wechsler (5) concluded that college athletes are at high risk for binge drinking and alcohol-related injuries. Despite the fact that many colleges and universities have programs that educate college athletes about the negative effects of drinking on health and performance, future prevention programs for athletes need to focus on the social and environmental influences that are exclusive to college athletes. "Programs also should take advantage of motives of athletes for self-limiting alcohol intake. Colleges, athletic departments, coaches, and sports medicine professionals are urged to act to help reduce athletes' risk of alcohol-related harms" (5). If athletes and coaches are made aware of the negative effects alcohol has on sports-related injuries and suboptimal athletic performance (7), prevention programs may be more effective. Shirreffs and Maughan (7) recommend "that alcohol should be avoided by the serious athlete."Table 2 provides a list of things to consider about alcohol and excercise performance
TABLE 2Some Things t...Image Tools
CONSEQUENCES OF EXERCISING WITH A HANGOVER
Individuals get hangovers primarily from dehydration and alcohol toxicity. When people experience hangovers, they are typically depressed, have a headache, and may be overly sensitive to external stimuli such as noise and light. The length of time for hangovers depends on the amount of alcohol consumed but also varies among individuals. Thus, the long-lasting effects of alcohol consumption, such as hangovers, will lead to decreased athletic performance. If an athlete drinks alcohol the night before or day of an athletic event (whether it be practice or a competition), his/her physical conditioning progress will be decreased. Furthermore, exercising with a hangover decreases aerobic capacity by about 11%; therefore, those who do not consume alcohol will have an edge over those who do (2-4,8).
IS ALCOHOL CONSUMPTION POSTEXERCISE BENEFICIAL?
There are some athletes who like to think that having a beer postexercise will help as a recovery drink; however, that is not the case! Although alcohol provides 7 Kcal/g and although some nutrients may be present in alcohol (e.g., beer has some nutrients), alcohol (beer included) is not an effective recovery drink postexercise.
Alcohol can actually result in greater dehydration because of its diuretic effect. Although some athletes believe that beer will provide carbohydrates postexercise, the energy provided by beer (or other alcoholic beverages) does not provide carbohydrate. Drinking alcohol postexercise may actually decrease muscle glycogen synthesis and storage at rest (which would impair future exercise bouts), may negatively impact gluconeogenesis (making new glucose), which would impair exercise performance, and may result in hypoglycemia (low blood glucose) during exercise, again, impairing exercise performance (2).
ACSM POSITION STATEMENT ON ALCOHOL AND ATHLETIC PERFORMANCE
The American College of Sports Medicine states that there is no benefit from alcohol consumption for sports performance. In fact, they emphasize that the use of alcohol can be detrimental to athletic performance. ACSM recommends that alcohol be avoided for at least 48 hours before an event. Postexercise, an athlete should first rehydrate properly with water and/or sports beverages before any alcohol consumption (1).
Alcohol is a recreational drug that physiologically and cognitively impairs athletic performance. Alcohol consumption has been shown to increase sports-related injuries.
Athletes need to consider the amount and timing of alcohol consumption to assess its impact on their health, athletic performance, and life.