August 4, 2010
A lot of attention has focused on the problem of childhood obesity and inactivity, but there’s been little mention of the growing number of highly active kids engaged in competitive sports. These youth athletes push themselves physically and mentally to achieve impressive levels of athletic performance. The high training loads create unique nutritional demands. Kids are not just “little adults” and the rules of adult sports nutrition do not necessarily apply.
A highly active youth athlete requires first and foremost an adequate number of calories to fuel not only the strenuous exercise regimen but also optimal growth and development. Athletes involved in endurance sports, aesthetic sports like gymnastics and cheerleading, and weight-class sports are at highest risk of not consuming adequate calories. Athletes can get a general idea of how many calories they need per day based on their age, weight, height, and activity level at MyPyramid.gov. The website also provides users with an individualized eating plan which can help athletes consume an optimally healthy diet including all of the essential nutrients they need like iron and calcium, which are deficient in a lot of preteens and teens. This individualized plan will work for most kids, though athletes should be sure to let hunger be their guide and choose nutrient-dense meals and snacks to fuel their activity.
While adults are advised to consume a carbohydrate-rich food within 30 minutes of finishing exercise for optimal recovery and then to have an overall increased protein intake to help rebuild muscles, nutrient recommendations for kids are a little less clear. The Recommended Dietary Allowance of carbohydrate for most kids is 130grams per day. Ideally athletes will get this from a diet rich in whole grains like cereals, rice, and pasta; fruits and vegetables; and limited in simple sugars. This recommended amount is based on the body's needs to provide glucose for brain development and doesn't include the needs for active children to replenish glucose stores. But kids metabolize sugars differently than adults and it is not entirely clear if and how much more carbohydrate youth athletes need for optimal performance. Likewise, it is not clear if kids involved in long-distance endurance events benefit from carbohydrate loading the same way adults do. Generally, most youth athletes will do well eating a healthy, nutrient-dense diet that contains at least 50% of calories from carbohydrate. As far as protein intake goes, most athletes will meet their protein needs with the standard recommendation of 0.8-1.2grams of protein/kg/day. Some athletes may have higher needs, but most will spontaneously increase their caloric and protein intake. Any protein consumed in excess of what the body needs will likely be used as energy or stored as fat.
In addition to healthful eating habits, staying hydrated is extremely important for young athletes. It is well known that kids have a more difficult time regulating body temperature, especially in extreme environments like a hot and humid summer day. In general, kids should aim to drink as much in fluids as they lose in body weight during an exercise sessions. That is, ideally they would weigh themselves pre- and post-exercise and make up the difference with fluid intake. Even a 1% decrease in body weight from sweating decreases endurance in kids. Or more simply, kids should be reminded and encouraged to stay adequately hydrated while exercising, and let thirst be their guide. About 7 million adolescents in the U.S. consume sports drinks. The limited amount of research that's been done suggests that while athletes feel like the drinks are helping them, there seems to be little effect on performance except in cases of athletes exercising for prolonged periods in hot temperatures.
So how should you put all of this into action? Check out a sample meal plan for your athlete at MyPyramid.gov. Then, divide the recommended types of food into a daily plan based on the athlete’s exercise schedule. Pregame meals should be eaten about 1.5 to 3 hours before the event. Go for easily-digestible high-carbohydrate with moderate protein like some pasta with ground turkey. Your child athlete might do well with a glass of low-fat chocolate milk or a granola bar with an orange shortly after a moderately-strenuous practice or game. Or if an all-day tournament is underway, snacks like these which contain about 200-300 calories spaced throughout the day will help sustain energy. Fluids should be emphasized throughout the game or practice and sports drinks might be a good idea for events in warm temperatures lasting longer than about an hour. A post-game dinner of pizza loaded with veggies on a whole grain crust would give an athlete a decent number of calories and nutrients to get her ready for the next day.
Ultimately, when it comes to youth sports nutrition, the goal is for your youth athlete to consume enough calories and fluids to fuel the exercise and enough nutrients to meet the body’s demands for growth and strength.
By Natalie Digate Muth
Natalie Digate Muth, MD, MPH, RD, FAAPNatalie Digate Muth, MD, MPH, RD, FAAP is the Healthcare Solutions Director for the American Council on Exercise, a board-certified pediatrician and Fellow of the American Academy of Pediatrics, a Diplomat of the American Board of Obesity Medicine, registered dietitian and board-certified specialist in sports dietetics, and ACE-certified health coach. She is the author of "Eat Your Vegetables" and Other Mistakes Parents Make: Redefining How to Raise Healthy Eaters" and the upcoming textbook "Sports Nutrition for Health Professionals". She has been ACE certified since 1998.