DEAR DR. DONOHUE: When and what should someone eat before he or she plays a major game or has a long practice? I have three children, two boys and one girl. All are on athletic teams, and all play different sports. Their games and practices are never at the same time of day. I have no idea what to serve them before a game or practice, or when to serve it. What is best? – R.F.

ANSWER: Try to have your children eat four hours before a big game or a long practice. It takes that long for food to completely leave the stomach. If four hours is impossible, then cut down the size of the meal.

Sports nutritionists recommend that the pregame meal emphasizes carbohydrates. Muscles used stored carbohydrates as their chief source of energy. Glycogen is the form of carbohydrates stored in muscle. After eight to 12 hours of not eating (a night’s sleep), the muscles’ glycogen reserves are on the low side. Replenishing those reserves prevents an athlete from tiring out quickly. If an athletic competition is held early in the morning, this presents a problem.

Examples of carbohydrates are pastas – macaroni, spaghetti, ravioli, pancakes, cereals – and fruits and vegetables like baked potatoes, sweet potatoes, peas and carrots. If a cereal is the main dish, it should be a low-fiber cereal so it doesn’t lead to production of intestinal gas and bloating.

Fats and fried foods, including gravies, aren’t good pregame or pre-exercise foods. They stay in the stomach too long.

Proteins are fine. They help rebuild muscles, but protein doesn’t have to be emphasized. Meat is an example of protein food.

Hydration is also important. Your children ought to drink two or three full glasses of water with the meal and drink another glass 20 minutes before the game or the exercise.

Another point worth mentioning is eating after a long game or a hard practice. Eating something within half an hour of strenuous exertion restores muscle glycogen rapidly. A milkshake is a good choice.

DEAR DR. DONOHUE: Is it better to lose weight by exercising or by dieting? I know you’re supposed to do both, but I wonder which one provides a faster weight loss. – D.D.

ANSWER: If you look at calorie-burning charts, charts that specify how much exercise burns how many calories, you’re in for a surprise. It takes a lot of vigorous work to burn only a few calories. The message is that taming the appetite is a must for anyone wanting to lose weight. Dieting is the faster way to lose weight.

However, dieting causes a person to lose protein calories as well as fat calories. Losing protein (substitute muscle) isn’t desirable. Exercising makes a person lose relatively more fat calories than protein calories — a more desirable weight loss. The message is do both: Exercise and restrict calories.

DEAR DR. DONOHUE: Should runners strength train? If the answer is yes, how do you go about it? Specifically, what kinds of leg exercises are done? I am a long-distance runner, but there’s no formal weight-training program for us at our school. – M.L.

ANSWER: Runners need strong legs for endurance, power and prevention of injuries. Weightlifting exercise is the best way to achieve those goals. As an aside, don’t neglect upper-body weight training. You might not need it for your sport, but you need it for a well-balanced body. Squats are good exercises. Rest a barbell behind your neck and on your shoulders. Bend the knees until the thighs are parallel with the floor. Don’t squat until your buttocks touch your heels; that kind of extreme squat can hurt your knees. Choose a weight that allows you to do eight consecutive squats, then rest and do two more sets. When you can squat 12 times, increase the weight by about five pounds. Rise on toes with a barbell in the same position as you had it for squats is an exercise for your calves. If you have a sturdy platform, let your heels project over its edge so you can lower the heels before rising on your toes.

Dr. Donohue regrets that he is unable to answer individual letters, but he will incorporate them in his column whenever possible. Readers may write him or request an order form of available health newsletters at P.O. Box 536475, Orlando, FL 32853-6475. Readers may also order health newsletters from www.rbmamall.com.