DEAR DR. DONOHUE: Are athletes wasting time in developing muscles they might not need? Could they spend their time better by engaging in their sports? Would DiMaggio, Williams, Mays, Laver and Jordan have been better athletes had they lifted weights? – R.G.

ANSWER: No one disputes that strength and endurance improve athletic performance – running, jumping, hitting, throwing, whatever. Weight-lifting – resistance exercise – is one of the best ways to build muscle power. If this weren’t true, professional teams would not spend money on strength coaches. I can’t say if DiMaggio and the rest would have been better athletes if they had lifted weights. Maybe they would have been. Maybe they did.

An athlete cannot concentrate on building muscle power only in those muscles that appear to be the ones most involved in carrying out the motions of his or her sport. A pitcher who exercises only the arm and shoulder muscles of the throwing arm misses an important element true for most athletic motions. The speed of a ball comes not just from the upper body muscles. It takes leg, hip, back and abdominal muscles to impart force to throw a ball.

Nothing, however, supplants practicing the skills of any sport. A strong person is not necessarily a strong batter. It takes practice to coordinate eye, arm and hand movements to meet the ball at precisely the right time, and that skill is obtained only by swinging a bat at a ball many, many times.

You do have a valid point. Transferring gains in strength that come from lifting weights to gains in a particular athletic skill is not automatic. Muscles have to be exercised in the same way they’re used in a particular sport to improve the motions of that sport. If batters, for example, want to build muscles that impart more power to their batting swing, they have to exercise with weights in exactly the same manner that they swing a bat. That is called sport-specific exercise, and it takes a little imagination to devise resistance exercises that mimic the particular athletic moves of any given sport.

DEAR DR. DONOHUE: I am on a low-carb diet to lose weight. I am also training to be a distance runner. I know that distance runners needs lots of carbs. Does that mean my diet is defeating my running goal? – R.N.

ANSWER: If you intend to be a dedicated distance runner, it’s safe to say you don’t have to worry too much about limiting calories – carbohydrate, fat or protein calories. Have you ever seen an overweight distance runner?

A low-carbohydrate diet is not a good diet for an endurance athlete. Muscle endurance depends on a good supply of muscle glycogen – stored muscle sugar. Without enough glycogen, a runner tires quickly.

Before any very long race, distance runners should increase the amount of carbohydrates they eat. They need at least 3 grams a day of carbohydrate for every pound of body weight. A person weighing 170 pounds would need 510 grams of carbohydrate each day in the three to five days before running any long-distance event. Let me give you some examples of high-carbohydrate foods: 1 cup of cooked spaghetti has 40 grams of carbohydrates; 1 ounce of whole-wheat bread, 13; 1 cup of sweetened applesauce, 50; one banana, 27; half a cup of baked beans, 32.

DEAR DR. DONOHUE: What do you think of running on sand? I live near a beach, and I like to run on sand. I am trying to get in shape for football season. Someone told me this is not good for you. Why not? – G.P.

ANSWER: It’s OK to run on sand. In fact, it takes more energy to run on sand. However, soft sand is unstable, so it’s easy to twist an ankle while running on it. Go at this slowly to get experience on how to maintain balance while running on sand.

DEAR DR. DONOHUE: What can you tell me about hypertrophic cardiomyopathy? My 18-year-old niece died of it. She was on her school’s volleyball team, and she died while playing in a game. An autopsy provided the diagnosis. She had been in excellent health and quite athletic all her life. She has two other sisters and a younger brother. Could they have it also? – M.C.

ANSWER: Many things cause heart-muscle trouble – clogged heart arteries, high blood pressure and heart-valve malfunctions. Cardiomyopathy, however, is heart-muscle trouble that arises directly from the heart muscle without outside influence. “Hypertrophy” indicates that the problem is one of muscle overgrowth, with muscle fibers not lined up as they should be.

The problem runs in families, so, yes, your other nieces and your nephew should be examined. The heart of a person who has the condition enlarges throughout childhood, adolescence and young adult life and then tends to stabilize in adulthood.

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.

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