DEAR DR. DONOHUE: I am 75 and have been athletic all my life. I have had to stop all sports because I have no balance. I have seen many doctors, including neurologists and ear, nose and throat doctors. I have had many tests and gone through many scans, but no one can tell me what’s wrong or how to right it. Can you? – R.J.

ANSWER: You took the right steps. You sought the opinions of experts and submitted to many tests to find a physical cause for balance loss. For some people, a search into medicines can sometimes identify one that is upsetting equilibrium. Where do you go from here? I can make a few suggestions.

Aging decreases muscle strength, and that is a remediable factor in maintaining balance. Strengthening exercises abound, as do books on how to perform them. I leave that to you.

Aging also delays the relay of information to the brain from nerves, spinal cord and radar stations in muscles, joints and tendons that tell it where the body happens to be at any given moment. The brain immediately makes the necessary position adjustments to keep us from toppling over.

The following exercises help re-train the brain and the body’s radar stations to react more quickly. All of them must be done with another person in attendance. That person can grab hold if you are on the verge of falling.

(1) Holding onto the back of a chair, rise on tiptoes eight to 12 times, rest and repeat. (2) Walk with the heel of the forward foot contacting the toes of the back foot. (3) Walk on heels only. Then walk on toes. (4) Stand on one leg for 30 to 60 seconds; you can hold onto a chair to steady yourself. Switch legs and repeat five times. (5) Rise from a chair and then sit down again. Repeat this drill for three minutes or as long as you can do so comfortably. When you have gained confidence, do the exercise with arms folded across the chest.

Don’t do any of the above if it makes you unsteady, and don’t do any of them without a capable spotter at your side and at the ready to rescue you from a fall.

DEAR DR. DONOHUE: Is bowling considered to be an exercise? I love to bowl, and it is the only kind of exercise I get. – F.J.

ANSWER: A 175-pound bowler burns about 100 calories in 25 minutes of bowling. So, yes, it is a form of exercise. It is not the most taxing exercise, and it would be a good idea to fit jogging, swimming or bike riding into your schedule.

DEAR DR. DONOHUE: My son will be 9 soon. He is 4 feet 10 inches tall and weighs 57 pounds. His stepfather has knowledge of weightlifting. Can he safely start weightlifting? How should he start? – T.C.

DEAR DR. DONOHUE: Is 12 too young to begin bodybuilding? My son plays baseball and football and would like to increase his strength. -J.C.

ANSWER: Children as young as 6 can lift weights if they are supervised, don’t try to lift heavy weights, perform the lifts strictly by the book and take at least one day off between days given to lifting.

Formerly, the party line taught that weightlifting before the surge of hormones at puberty was a waste of time. Hormones do influence muscle size and strength, but it has been shown that prepubertal children can increase muscle strength with a weightlifting program. Muscle size, however, does not increase as much as it does when puberty sets in.

The party line also taught that weightlifting would stunt younger children’s growth by injuring their growth plates. Growth plates are sections of bones that have not yet become bone. They permit elongation of bones. Sensibly done weightlifting does not injure growth plates.

The child should use a weight that he or she can lift 10 times in a row. When the child can lift that weight 15 times comfortably, then it is safe to increase the weight 5 percent to 10 percent.

DEAR DR. DONOHUE: I am a healthy 56-year-old woman who happens to be 25 pounds overweight. My blood pressure has always been good. My problem is my pulse. It usually runs from 98 to 110 when I am resting. My husband’s pulse is always in the range of 64 to 70. My doctor has never mentioned doing anything for the pulse. Does this high pulse pose a problem? – T.C.

ANSWER: The upper limit for a normal pulse is 100 beats a minute. The pulse rate and the heartbeat are one and the same. You are not too far from the 100 mark.

Heart failure, infection, anemia, an imbalance of potassium and sodium, an overactive thyroid gland, caffeine and stress – both physical and mental – can speed up the pulse. You have been under a doctor’s care, and none of these illnesses has surfaced.

You might, then, represent a normal variation. How do you feel? If you feel fine, then the best advice I can give you is to stop taking your pulse.

In all probability, you have no grounds for concern.

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.