Nutrition for Young Athletes: Fueling Up Before the Game August 6, 2007
"We have a significant problem in the United States with lack of knowledge of proper nutrition for athletes," believes Round Rock area family physician Norma E. Anderson, MD. "For example, it is surprisingly common for them to use unhealthy methods to gain or lose weight. Not only can these choices be dangerous to health and growth, but they are counterproductive to maximal sports performance."
This week in the second part of her discussion of healthy nutrition for young athletes, Dr. Anderson, provides information on how to choose a healthy, balanced diet drawn from all food groups plus special concerns that players and families should know about. She cites details on healthy weight control from the American Academy of Pediatrics Policy Statement on Promotion of Healthy Weight-Control Practices in Young Athletes. The information regarding basic nutrients and competition events is taken largely from The Journal of School Nursing.
The American Academy of Pediatrics Policy Statement says: 'There is no substitute for a healthy diet consisting of a variety of foods from all food groups with enough energy (calories) to support growth, daily physical activities, and sports activities.'
"That means most athletes need to consume at least 2,000 calories per day," says Dr. Anderson. "Some will need more; the amount needed depends on the rate of growth (more is needed during growth spurts), the amount of exercise engaged in, and the height and weight of the individual. It may be helpful to know that 1 gram (g) of carbohydrate supplies 4.5 calories. The same is true of protein, 4.5 calories per g; fat supplies 9 calories per g."
Dr. Anderson's recommendations include:
Carbohydrates: Athletes need at least 50% of their total calories from carbohydrates, the main energy source for physical activity. Carbohydrates fuel the muscles.
Protein: Ten to 15 percent of total calories should come from protein. Athletes need slightly more protein than those who are less active.
Most athletes need 1.2-2.0 grams of protein per kilogram of body weight per day. (To figure ones weight in kg, divide weight in pounds by 2.21.)
The upper end of this range (1.6-1.7 g of protein per kg of body weight per day) is sufficient for strength-trained athletes, such as weight-lifters and football players.
Endurance athletes need 1.2-1.4 g of protein per kg of body weight per day.
Many people do not realize that there is a limit to the amount of protein the body can use each day; eating more than this limit does not help in increasing muscle mass or performance and can even be detrimental to health, leading to calcium loss and other problems.
Protein needs can be supplied easily by the typical American diet, which contains two to three times the amount necessary so protein supplements are not recommended. Vegetarians should learn more about how to consume adequate protein from plant sources, but this also should be accomplished with foods rather than supplements. The topic of vegetarian diets is beyond the scope of this summary, but information is available at www.healthierus.gov/guidelines.
Fats: Athletes need 20 to 25 percent of total calories from fat. Fats are important for allowing the body to absorb fat-soluble vitamins. Some types of fat are 'essential' in and of themselves, meaning that the body cannot produce these types of required fatty acids.
Other nutrients: Most athletes eating a balanced, varied diet with proper choices from all the food groups will meet their needs for vitamins and minerals without taking supplements. However, some athletes, in particular those who try to lose weight inappropriately, may be at risk of deficiencies, especially of calcium and iron. This is especially true in girls. Also, some endurance athletes have been found to have iron deficiency.
"An excellent guide to nutrition for the general population, including children, is the Dietary Guidelines for Americans from the U.S. Department of Health and Human Services & U.S. Department of Agriculture, 2005. These guidelines, along with a more user-friendly brochure for laypersons, are available online at www.healthierus.gov/dietaryguidelines," adds Dr. Anderson.
Eating Before, During and After Competition Events
Dr. Anderson recommends the following:
Before: Best eaten at least three or four hours before competition, the pre-event meal should be high in complex carbohydrates (starch) and fluid, moderate in protein, and low in fat, fiber, and caffeine. Note that in general the athlete should eat a high-fiber diet, but the pre-event meal is an exception; fiber in large quantities before an event may lead to gas and discomfort during the event.
During: Especially during long endurance events, it is helpful to consume 30-60 g/hr of carbohydrate; this can be done with sports drinks.
After: A mixed carbohydrate and protein snack or meal should follow the event; carbohydrate to replenish glycogen (muscle energy stores), and moderate protein for muscle repair. (And dont forget to drink extra fluids to replace losses, as discussed in the first part of Nutrition For Young Athletes: Consuming Fluids. An example of a good post-exercise snack is milk or yogurt with a cereal bar. Add a banana or fruit juice if more energy is needed, such as for male athletes or those with greater calorie expenditure. Alternatively, a sports drink (24 oz, or up to 32 oz for males or greater calorie expenditure) will at least supply some carbohydrate to get the refueling process started, though protein would be lacking.
Issues in Weight Control for Athletes
For some sports, such as football, rugby, basketball, and power lifting, athletes are motivated to weigh more, or bulk up. For other sports, such as gymnastics, figure skating, and wrestling, athletes often desire to lose weight. In other circumstances, athletes who are truly overweight or underweight may need to lose or gain weight for optimal health.
"There are real risks to incorrect approaches to losing or gaining weight," reports Dr. Anderson. "Under-nutrition or less than optimal nutrition can lead to fatigue, poor recovery, illness, loss of muscle mass, and risk of weakened bones prone to fractures (osteoporosis). A commonly recognized and risky syndrome in girls and women is the female athlete triad, consisting of disordered eating, loss of monthly menstrual cycles, and osteoporosis."
"Often young female athletes purge with or without binging, over-exercise in an attempt to lose weight, and purposefully consume too few calories to sustain their needs. Also, girls who try to lose weight are at special risk of iron and calcium deficiency. On the other hand, overeating inappropriately in an attempt to gain weight leads to excess body fat, which can impair speed, endurance, agility, and the ability to acclimatize to heat. Also, the overweight athlete will be at risk later in life for high cholesterol, heart disease, high blood pressure, diabetes, and gallstones. Frequently, athletes use supplements, which do not have proven benefits and may be harmful, or anabolic steroids, which are known to be harmful to health, rather than learning the basics of sound nutrition and taking a look at their real nutritional needs and training program."
Coaches Can Help
"Coaches should be careful in what they say to athletes about weight," believes Dr. Anderson. Research has shown that when a coach recommends weight loss or weight gain to an athlete, frequently the athlete will employ unhealthy and ineffective methods to lose or gain weight, rather than consulting with professionals knowledgeable in nutrition. A good coach can help young athletes by advising them to consult their physician for information and referral to a registered dietitian.
The following are useful recommendations:
In sports for which weigh-ins are required, weight and body composition (percentage fat) should be measured one or two times per year, to determine minimal allowable weight when the athlete is well hydrated.
Weigh-ins for competition should be performed immediately before competition, to prevent athletes from intentionally dehydrating themselves to lose weight, then re-hydrating for the competition.
Males need at least seven percent body fat; even this level may be too low for some individuals.
Females need to consume enough calories to meet their energy expenditures and have normal monthly menstrual periods; there are no body fat percentage recommendations for female athletes.
Healthy approaches to weight gain or loss
"The following are some highlights from the American Academy of Pediatrics Policy Statement that can provide guidelines for young athletes regarding weight loss or gain," continues Dr. Anderson.
Cautions: First of all, athletes should consult their physician to determine if indeed weight gain or loss is appropriate, and to plan how the weight change needs to occur; a registered dietitian may be consulted. Weight loss for sports purposes never should be started before the 9th grade. Any program for losing or gaining weight should be started early, before the athletic season, to allow a gradual weight gain or loss over a realistic time frame. No more than 1.5 percent of the body weight should be gained or lost per week. This gradual approach will allow weight gain to be muscle mass, and weight loss to be fat loss, when done with an appropriate training program consisting of both strength training and conditioning. It is important to maintain the desired weight once it is reached, avoiding great fluctuations. Ergogenic aids and non-therapeutic supplements should be prohibited.
Healthy weight gain: To build 1 lb of muscle in 1 week, one must (1) consume 2000-2500 calories more than one expends (over the course of the week), (2) consume 1.5 to 1.75 g of protein per kg of body weight per day, and (3) participate in strength training.
Healthy weight loss: Again, caution should be exercised, first discussing with the physician and ideally with a registered dietitian, regarding the need for weight loss and a sound plan. Weight loss should be gradual and should not exceed 1.5% of the total body weight, or 1-2 lb, each week. Weight loss beyond these guidelines results in the breakdown of muscle, making an athlete weaker. The ideal way (to lose 1 lb of fat in 1 week) is to consume 1750 calories fewer during the week and to burn 1750 calories more during the week by exercising. Even when trying to lose weight, most athletes still need at least 2000 calories per day; the actual number of calories needed depends on many factors and must provide for growth, daily living, building and repairing muscles, and fueling sports activities. Equally important, the diet should remain balanced, following the food pyramid to include all food groups.
Special issues for girls (recap): The female athlete triad is a combination of disordered eating (not eating enough to sustain the bodys needs for activity and growth) to the point that the monthly menstrual cycles stop occurring; the decreased estrogen level that results from this scenario can lead to osteoporosis, or bone thinning, with risk of fractures. In addition to these health risks, girls should be reminded that when energy (calorie) intake is limited, the body breaks down muscle as well as its fat stores for energy; this results in loss of strength and impaired performance. Also important to note, girls who under-eat are especially at risk for deficiencies of calcium and iron.
"It is important for athletes and their families to understand how to plan a healthy diet. While much of the knowledge needed is the same as that for the general population, there are some special issues for young athletes, including proper hydration, consuming enough calories to fuel daily living and growing in addition to sports, and a healthy approach to weight control for those seeking to gain or lose weight for athletic or general health reasons," says Dr. Anderson.
She encourages young athletes to seek professional advice and counseling from their physician and a registered dietitian regarding these issues. There are many other influences that young athletes face frequently, from supplement labels claiming various (unproven) benefits to personal acquaintances and other figures in the athletic world; athletes and their families should be careful to make informed and healthy choices.
Committee on Sports Medicine and Fitness, American Academy of Pediatrics. Promotion of Healthy Weight-Control Practices in Young Athletes, Pediatrics, 2005; 116; 1557-1564.
Cotugna, N, Vickerey, C., and McBee, S. Sports Nutrition for Young Athletes, The Journal of School Nursing, 2005; 6; 323-328.
Ray, T. and Fowler, R. Current Issues in Sports Nutrition in Athletes, Southern Medical Journal, 2004; 97; 863-866.
Norma E. Anderson, MD
Sundance Family Health Center
Dr. Anderson is a family physician, board-certified by the
American Board of Family Medicine. She completed her Family
Medicine residency in 1995 in Santa Rosa, California, at
Community Hospital (later named Sutter Medical Center),
affiliated with the University of California at San Francisco.
She practiced in Cedar Rapids, Iowa until 1997, Rich Square and
Roanoke Rapids, North Carolina until 1999, then in Mission,
Texas until 2006.
Dr. Anderson enjoys the personal connection she makes with her patients and values the opportunity to take care of a great diversity of people, including all ages from newborns through senior citizens. She is interested in women's health issues and preventive health care.