DEAR DR. DONOHUE: I am a 66-year-old woman and have never exercised in my life. I have done lots of hard work, like shoveling snow, mowing the lawn, planting a half-acre garden and doing all the daily household chores. I want to start a formal exercise program. What is the minimum and maximum time for exercise? How often does a person have to do it? How hard should a person exercise? Please don’t use words like “brisk.” I don’t know what that means. – M.L.

ANSWER: No one is too old to start an exercise program. However, it is wise for an older person to see the doctor before beginning any exercise routine. People can and do sometimes have silent heart disease, and the first they learn of it is when they have a heart attack. I don’t want exercise to be the occasion of that.

The minimum amount of exercise is 30 minutes a day. You might have read that recently a new limit of one hour a day has been advised. Half an hour will give you more than enough exercise to benefit your heart and lower your blood pressure. An hour a day gives you a bit more benefit, and it takes an hour of exercise a day to lose weight without going on a diet. A half-hour will do for weight loss if you both diet and exercise.

You don’t have to do the entire 30 (or 60) minutes in one stretch. You can break it down into two 15-minute sessions or three 10-minute ones. Less than five minutes does not give the heart a decent workout.

If your doctor clears you for exercise and puts no limit on it, you can exercise for as long as you want. There is no maximum. Your muscles and your lungs will tell you how long you can keep going.

How often? As many days a week as you can. If you can manage only three days, that is better than no days.

How hard? Let me use walking to give you an idea of the intensity. Walking a mile in 15 to 20 minutes is the pace that brings results. If you can’t walk that fast, then don’t. Let your body set the intensity level for your exercise.

DEAR DR. DONOHUE: My left heel began to hurt so much that I could barely walk. I finally saw my doctor, who told me I have plantar fasciitis. He has me soaking the foot three times a day in warm water and taking Aleve. Is there something else I could do to get myself over this more quickly? – V.B.

ANSWER: The planter fascia is a band of tough tissue that runs from the bottom of the heel to the front of the foot. It supports foot bones and stabilizes the foot’s arch. Inflammation of the fascia is a common cause of heel pain. The pain is felt on the bottom of the foot at the front of the heel bone.

Try this. Sit. Cross the leg with the painful heel over the good leg. Reach down and put your right hand under the front of your left foot with fingertips at the bottom of the toes. Pull the foot upward until you feel a stretch in your arch. Hold it there for 10 seconds. Let go of the foot and give it a brief rest. Then repeat the stretch for a total of 10 times. Do this procedure three times a day.

You might want to try splinting the foot during sleep. A friend can help you put the splint on. All you need is a piece of wood as wide and as long as your foot. Put the board under your foot, and your friend can attach it by running adhesive tape from one side of your ankle, under the board and then across to the other side so your foot is in a propped-up position all night long.

If the exercise bit works, you can thank Dr. Benedict di Giovanni, who described it in a sports medicine journal.

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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