DEAR DR. DONOHUE: I know you have written about heel pain in the past, but I didn’t have it then; I do now. I’d like to know its cause and treatment. Mine is so bad that I can hardly hobble around. I used to be a dedicated jogger. – W.H.

ANSWER: There are some 27 causes of heel pain. Out of those 27, I’ll pick two of the most common causes, but you must check with your doctor for a specific diagnosis and a specific treatment.

Achilles tendonitis is pain in the back of the heel, around the spot where the topmost part of the back of the shoe reaches. The tendon suffers from microscopic tears. People don’t give it enough time to heal, so the tears multiply and the pain intensifies. Achilles tendonitis also makes the heel quite stiff in the early morning, when you get out of bed.

Rest is a must until the pain goes away. Anti-inflammatory drugs – Advil, Aleve, Motrin, etc. – relieve pain and suppress inflammation. A cortisone injection into the painful area often brings quick relief. The injection is not into the tendon. Injecting cortisone into a tendon weakens it. Once the pain leaves, stretch the tendon by standing with the toes on the edge of the first step in a staircase. Rise up on your toes and lower yourself to the point where the heels are below the level of the step. Repeat 10 times.

Plantar fasciitis is another frequent cause of heel pain. The plantar fascia is a dense sheet of tissue that attaches to the front part of the bottom of the heel. Plantar fasciitis pain is felt in the center of the bottom of the heel. Rest, anti-inflammatory drugs and a cortisone injection work for this too. A heel pad or cup takes pressure off the fascia. Splinting the foot at night, so that the toes point up when lying on the back, hastens healing. When free of pain, stretch the fascia by crossing one leg or the other. Grab the toes of the crossed-over leg and pull them toward the shin. Hold that position for 10 or 15 seconds and repeat 10 times or more. Do this three times a day.

DEAR DR. DONOHUE: I have been wondering what the value of one-minute rest between sets is if you do three sets of 10 exercises. I understand that the muscles need rest. Is the value of the exercise less if a person does two sets of 15 exercises and takes a rest of only one minute between sets? – V.S.

ANSWER: The generation of muscle fuel dictates the amount of time to be taken between sets of exercise. (A set is a certain number of repeated lifts – repetitions or reps – done consecutively, with no pause between lifts.) With a 5-minute rest, the muscle can regenerate 99.9 percent of the energy needed to sustain brief but strenuous exercise. In 2.5 minutes, 95 percent returns. With 1 minute of rest, 75 percent is available. One to two minutes is a good rest period between sets.

You can do 8, 12, 15 or 20 reps in a set and rest one to two minutes between sets. The general rule is to lift a weight you can lift eight consecutive times and work toward 12 consecutive lifts. When you make it to 12, you can add more weight and reduce the number of lifts to eight again.

DEAR DR. DONOHUE: My teenage granddaughter is staying with us for two months this summer. We live on a lake, and she’s an accomplished swimmer. She swims for hours every day and has quite a tan. She also has white spots on her shoulders and neck, and I think they’re spreading. They don’t bother her. What is this? – C.S.

ANSWER: Your description points to tinea versicolor, a fungal infection. It causes pigment-making cells to shrivel. Selenium sulfide is a lotion applied to the skin, left on for 10 minutes and then washed off. It works, and it’s cheap. You apply it for seven days and thereafter once a month to prevent a return. The white spots don’t immediately tan again. It takes time for the pigment cells to recover.

DEAR DR. DONOHUE: My next-door neighbor has just been told he has Lou Gehrig’s disease. He depends on us for everything, since he has no relatives that we know of. We don’t know much about this illness. What can we expect will happen to him? – D.K.

ANSWER: Muscles move because nerve cells in the brain and spinal cord tell them to. In Lou Gehrig’s disease (amyotrophic lateral sclerosis – ALS), those commander nerve cells die. There follows a progressive weakness of muscles that reaches the point where ALS patients are bound to a wheelchair or their beds. Speech can be garbled, and swallowing becomes a challenge.

Breathing muscles can be so impaired that artificial ventilation is needed to stay alive. Sensation remains intact, and thinking stays clear.

Ritulek is a medicine that can extend a patient’s life for a while, but it is not a cure drug.

Physical therapists keep muscles limber, and occupational therapists provide appliances that ease a patient’s life.

For example, finger-extension splints, provided by the occupational therapist, permit ALS patients to hold on to objects with a firmer grip. Lou Gehrig, one of baseball’s greatest players, died of ALS in 1941.

You would do a big service to your neighbor by getting him in touch with the ALS Association. Its toll-free number is 1-800-782-4747, and its Web site is:

You can read a very touching account of an ALS patient in the book “Tuesdays With Morrie,” by Mitch Albom.

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

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