DEAR DR. DONOHUE: You wrote that exercise lowers cholesterol. That presents a dilemma for me. I have severe back problems and am overweight. I can walk only 100 yards before back pain makes me sit down. Thirty seconds of sitting permits me to go another 100 yards. Any suggestions on how I might get more exercise to help lose weight? – B.D.

I don’t know what your back problem is, so you must get a go-ahead from your doctor before doing any exercises.

How about biking? You don’t have to pedal with the profound waist bend professional cyclists adopt. You can adjust the seat and the handlebars to your comfort zone.

How about swimming? Most people with painful backs can manage to swim without increasing back pain.

Or how about a pool-based exercise program? Many YMCAs, for example, sponsor water aerobics. Water buoyancy takes stress off your joints and your back.

If there is no water-exercise program near you, I’ll give you an outline of two exercises you can do by yourself in a pool – if your doctor gives you an OK.

You’ll need a flotation belt to keep your body vertical while you are in chest-deep water. Most sporting-goods stores have them in stock. Two brand names are AquaJogger and Wave Belt.

With the flotation device on, run just as you would run on land. You can do this in chest-deep water, so your feet strike the pool bottom, or in deeper water where your feet don’t touch the pool bottom.

Another exercise is knee bends. With your back against the side of the pool, bend your knees to 90 degrees and hold the position for one minute. Do this exercise in waist-deep water. Repeat the exercise as many times as you can without pain.

DEAR DR. DONOHUE: I am a 77-year-old man who is in good health and exercises regularly. I run and do weightlifting exercises. I have always had a flat stomach – until the past few months. Now my stomach protrudes. My doctor says age makes stomach muscles weaker. I would like your opinion. – J.M.

If you doctor is sure your protruding abdomen is not the result of fluid in the abdominal cavity or some process other than fat accumulation, you can regain your flat stomach.

Lie on the floor and cup your ears lightly with your hands. Bend your knees until your lower legs make a 45-degree angle with your thighs. Then start pumping your legs just as you would when riding a bike. Keep pedaling and touch your right elbow to your left knee, return to the neutral position, and then touch your left elbow to your right knee. This is a vigorous exercise, and you have to have a heart that can safely support exercise of this intensity. Make sure about that before trying it.

Another abdominal exercise is to lie on the floor and raise your knees upward toward your chest. At the same time, lift your shoulders and upper back off the floor so the shoulder blades clear the floor. Hold the raised position for as long as you can, return to the starting position and repeat the exercise.

How many repetitions of this exercise you do depends on what shape you are in. If, at first, you can do only one, that’s fine. In a week, you ought to manage three upward lifts. Keep increasing the number so long as you remain pain-free.

DEAR DR. DONOHUE: My kids bought me inline skates. I have mastered them, but they give me painful heels. I have had to retire the skates. Is this a common occurrence? – E.C.

Somewhat common. Skate wheels cause a vibration that affects many people’s feet. Some complain of numbness, while others develop pain. Occasionally, inline skating throws a person off balance after a skating session.

Reduce the amount of time you skate. Take many breaks while you skate. Put a cushioning pad inside the skates. The pain ought to go away in a short time.

DEAR DR. DONOHUE: My husband was and is an alcoholic. He used to drink two quarts or more of beer a day. His doctor noted that he has an anemia and took extensive tests. He called to say that my husband should quit drinking.

My question: Why the anemia? How is it related to alcohol? – H.H.

Excessive amounts of alcohol can deplete the body of folic acid (a B-vitamin) and iron. Depletion of either can lead to anemia.

Alcohol is a stomach irritant that can cause bleeding. The blood loss can be so small that a person does not recognize it. In time, an anemia results. Furthermore, an alcoholic’s red blood cells can have a short life span, dying before they should. That produces a red blood cell deficiency, and that is the definition of anemia.

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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