DEAR DR. DONOHUE: I am a high-school pitcher. Last year I got a sore shoulder toward the end of the season and had to sit out for four weeks. I don’t want that to happen this year. What kind of exercises should I do to prevent another sore shoulder? – A.G.

ANSWER: Close to half the velocity of a thrown ball comes from the pitcher’s stride and body rotation as he or she throws the ball. So you have to devote a good portion of your exercise time to developing your leg, hip and torso muscles.

Strengthening exercises for the arm and shoulder are, of course, important. I don’t want to name a particular book for muscle strengthening, because there are so many. You can make a trip to the library and find shelves of such books. Be sure not to concentrate only on your throwing arm, or you will end up with unbalanced muscle development.

I can suggest an exercise program that might not be familiar to you. It’s sport-specific muscle strengthening. Sport-specific exercise is the kind of muscle-building exercise that a person performs by enlisting the muscles used in his or her sport in a way that closely imitates the way they are used in performing the motions of that sport. For a pitcher, the motions would be throwing motions.

Find yourself a 2.5-pound ball (or any round object that roughly approximates a ball). With your right hand, lift the ball slightly above your head. Next, bring the ball to your left shoulder. Then swing the ball-holding hand quickly upward and to the right and release the ball.

A second exercise is done in a half-kneeling position, with your right knee on the ground and left knee bent. Hold the ball behind your head and then toss it to a friend who is standing.

Work up to a point where you can perform three sets of 10 repetitions of these exercises, with a 30-second rest between throws. I’ve described them for a right-hander. Lefties have to make the appropriate changes.

DEAR DR. DONOHUE: I am an active, 71-year-old male. I have been remiss in my aerobic and strengthening workouts for the past year but intend to get back to a routine.

I have heard and read that aerobic exercise and strengthening workouts should be done on alternate days of the week. I would like to combine the two each day for five days a week. Is that OK? – C.D.

ANSWER: For readers unfamiliar with exercise talk, aerobic exercise is the kind of exercise that gets the heart beating fast for a prolonged time period. Jogging, walking, swimming and biking are examples of aerobic exercise. It’s the exercise designed to keep the heart healthy.

Guidelines for aerobic exercise recommend that people perform them on most, if not all, days of the week. Those guidelines are universally accepted. If they are followed, that would leave no days for strengthening exercise if it were unhealthy to do both on the same day.

It’s perfectly healthy to engage in both aerobic exercise and weightlifting exercise on the same day.

It is not perfectly healthy to exercise the same muscles on two consecutive days in weightlifting. Muscles need a rest for recuperation and growth.

DEAR DR. DONOHUE: What can you tell me about Curves gyms? They have equipment set up in a circle where you do certain exercises for 30 seconds and then move to the next exercise machine until you have gone around all 10 machines, three times each, for a total workout of 30 minutes. It still takes 3,500 calories to lose a pound of fat, correct? – C.C.

ANSWER: I have never heard of Curves, but the program sounds exactly like circuit weight training. The exerciser moves quickly from one exercise machine to the next without taking any rest between machines. This kind of workout is an amalgamation of aerobic and weight-training exercise. It kills two birds with one stone. It’s a good way of fitting both kinds of exercises into a tight schedule.

Correct: Burning 3,500 calories is still required to lose a pound of fat.

DEAR DR. DONOHUE: What’s the difference between a hysterectomy and a total hysterectomy? When they speak of a total hysterectomy, does it mean that the ovaries were taken too? – P.G.

ANSWER: A hysterectomy is removal only of the uterus. A total hysterectomy is removal of the uterus and the cervix. The cervix is the necklike extension of the uterus that juts into the vagina. It’s the site of a common female cancer.

Removal of the uterus, cervix, ovaries and tubes is a total hysterectomy with bilateral (“both sides”) salpingo-oophorectomy (“tubes,” “ovary”).

Knowing what was removed is more than of academic interest. Removal of the cervix removes the necessity for a regular Pap smear.

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.