DEAR DR. DONOHUE: I am a good tennis player – in practice. During a match, my game falls to pieces. I move unnaturally and miss shots that I make during practice sessions. I think it’s because I choke. What can I do? – K.L.

Choking, or anxiety, happens to every performer. It happens to musicians when they play solo but not when they play with an orchestra. It happens to seasoned actors when they appear on the live stage. And it happens to many athletes, professionals included.

In a state of heightened anxiety, performance suffers. The heart is beating rapidly, but the rapid beat is not a help in execution of sport abilities. The heart races due to an outpouring of stress chemicals and hormones. Those hormones gear the body to flee a danger, but they destroy coordination. Muscles tense, and movements become robotic. Fine muscle control goes out the window. Concentration is shot. Things do fall apart.

You have to practice mental skills as hard as you practice physical ones.

Never, in practice or a game, make negative statements to yourself. Don’t say to yourself such things as “I’m losing because I’m no good.” Say upbeat things. “I’ve been playing really well this past week, and I can win this match easily.”

In the break between points, picture how you are going to serve or hit the ball. In your mind, see yourself throwing the ball upward to serve or swinging a backhand to win a point. This is mental imaging, and it distracts you from fixating on losing. It’s a habit that can be learned only through daily repetition.

Another trick is to exhale very slowly when you’re not running.

DEAR DR. DONOHUE: I am unhappy. Five months ago I decided to get more exercise. After I got started, I really got quite limber. I lost 10 pounds, my blood pressure went down, and I realized I have a body. However, three weeks ago, I pulled my hamstring muscles going up a steep hill. How long does it take hamstrings to heal? Will I be out of condition? – R.E.

Hamstring muscles are the ones on the backs of the thighs. Strains of the hamstrings are quite common in all sports.

It can take anywhere from two to 10 weeks for hamstrings to heal.

Rest is an essential ingredient in healing. You can still exercise your upper body. A rowing machine, for example, will keep your heart in condition. Your leg muscles will get out of condition. It will take as long to get them back in condition as it takes the strained hamstrings to heal.

When they heal, warm up before you walk or jog by running in place for a few minutes. Also adopt a stretching program. The impact of stretching on injury prevention is not known, but many experts are believers. This is due to their personal observations.

A good hamstring stretch is done while sitting on the floor with the legs straight out in front of you. Grab the ends of a towel with both hands. Flip the towel so the middle of it is lassoed around your feet. Pull yourself forward and downward so your chest and head come close to your legs. When you feel the stretch, hold it there for 10 to 15 seconds. Relax and repeat as many times as you can in comfort.

If things are not improving, you must see your doctor. Many conditions other than muscle strains cause the backs of the thighs to hurt.

DEAR DR. DONOHUE: The uppermost part of my left leg has gotten terribly sore. I play basketball. It hurts so much that I have not been able to play. My coach says it’s a groin strain. What is that? – O.B.

The groin is the area where the upper leg joins the abdomen. Pain is felt there when leg muscles that draw the legs together are pulled. It happens in sports where there is a lot of pivoting and accelerating. Don’t play until the pain resolves, and that usually happens in a matter of weeks.

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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