DEAR DR. DONOHUE: I am trying out for my high-school hockey team. What’s the best way for me to get in shape? Would running be as good a way as skating? Hurry. I don’t have a lot of time. – K.O.

ANSWER: I’m hurrying, but you didn’t give me much time.

Hockey is one of the most energy-demanding sports, as well as one requiring a multitude of unique athletic skills. Hockey players have to propel themselves forward, backward and side to side. They have to have endurance and speed. They must be strong and exceptionally agile.

About one-fifth of the time a hockey player is on the ice, he or she is engaged in high-intensity activity, skating at breakneck speed. The rest of the ice time is spent moving about but at a less-exhaustive pace. Hockey players, therefore, have to train aerobically – endurance training – and anaerobically – sprint training. You can do both off the ice, but there is no better way to gain the skill of a sport than by participating in the exact action that takes place while playing that sport. So, skating for hockey players is the better, but not the only, way to train. To attain sprinting ability, skate (or run) as fast as you can for 200 meters. Do at least six sprints. Between sprints, take a rest that is four times as long as the time it took you to skate the sprint. With each practice, make it your goal to cut the time it takes to skate the 200 meters – a little faster each time will make all the difference in the world by the time you reach hockey season.

You can vary the above by skating 100-meter distances and taking a rest of three times the time it took to skate that distance.

Endurance skating is exactly what the name says it is – skating for long periods of time. Skate for 15 minutes or more. If you can’t last 15 minutes, then skate for as long as you can. Each session, try to increase the time by 15 or more seconds.

Strength training and skill training I leave to your coach.

DEAR DR. DONOHUE: I notice that the tips of my big toes’ nails are flaking and have black streaks in them. Is this a fungus? If not, what could it be? – W.S.

ANSWER: That’s not a description that fits a fungal infection. What sports do you play? If you play any in which there are lots of quick stops and starts, you might be slamming your toes into the fronts of your shoes. It happens frequently to basketball and tennis players.

The solution is to wear shoes with cushioning in the front and with enough room to stop your toes from jamming the fronts of the shoes.

DEAR DR. DONOHUE: I am almost 84 and swim nonstop one or two miles every day without an ache or a pain. On land, I cannot walk 20 yards because of severe pain in my lower legs. Why the tremendous difference between water and land environments? – S.M.

ANSWER: Water buoys body weight. In water, your legs are not forced to support body weight like they are on land. That explains most of the difference, and that’s normal.

However, it is not normal to have leg pain after walking only 20 yards. Such pain is often a sign of circulatory problems – a block in blood flow through the leg arteries. If you feel the pain in your calves, that makes artery blockage an even greater probability. That’s called claudication. It’s pain that comes on with activity and leaves with rest. People can almost predict to the foot when the pain will arise.

Don’t delay in seeing a doctor about this.

DEAR DR. DONOHUE: I am only 32 and have had a kidney transplant. Can I exercise? – W.B.

ANSWER: Your doctor is the only one who can answer that question. Most transplant patients not only can exercise but are encouraged to do so. As proof of that, every two years the National Kidney Foundation sponsors the U.S. Transplant Games.

DEAR DR. DONOHUE: Will you be kind enough to write on a condition called edema? Both of my wife’s legs are swollen with fluid. We would like to find a cure for it. – J.S.

DEAR DR. DONOHUE: Does one get swelling of the ankles if there is kidney trouble? What other ailments would cause swelling? – M.J.

ANSWER: “Edema” is the Greek word for swelling, so it’s simply a fancy way of saying that. The cure for swelling hinges on finding its cause.

All body tissues and cells are bathed with fluid as though they were living in seawater. The fluid oozes out from blood vessels to nourish and hydrate body cells. Swelling, a fluid excess, happens when too much fluid leaks from the circulation.

This tissue fluid flows into vessels called lymphatics, which act like suction hoses to bring the fluid back into the circulation, where it can be refreshed and cleansed. Blockage of lymphatics can also cause swelling. Lymphatic-caused swelling can happen after some cancer surgery, for example, when lymphatics are removed along with the cancer. This kind of swelling is something I’ll have to discuss separately, since it is a vast topic.

Heart failure is high on the list of causes for swelling. A failing heart is such a poor pump that blood backs up in vessels and fluid leaks out. Treatment of that entails getting the heart to beat more strongly, usually with medicines.

Kidney failure definitely causes ankle swelling, because failing kidneys cannot keep protein in circulation. Circulating protein keeps too much fluid from escaping from blood vessels. These are only two examples of many. J.S., your wife’s doctor has to find the underlying cause. She can help matters by elevating her legs as much as she can for as long as she can, wearing compression stockings and limiting the amount of salt she uses.

The edema booklet details all edema causes and their treatment. Readers can obtain a copy by writing: Dr. Donohue – No. 106, Box 536475, Orlando, FL 32853-6475. Enclose a check or money order (no cash) for $4.50 U.S./$6.50 Can. with the recipient’s printed name and address. Please allow four weeks for delivery.

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.