DEAR DR. DONOHUE: My daughter is a diver. I cannot stand heights, and I wouldn’t even think of climbing up the steps to the high-dive platform. I have to close my eyes when she dives.

What are the risks to divers when hitting the water with such force? Do they develop neck arthritis later in life? – G.O.

Serious injuries from regulated diving programs and contests are few and far between. The impact of a diver striking the water from great heights is pretty much dissipated by the hands and arms striking the water before the head and neck.

There is no evidence that shows divers have more neck arthritis in later life than do nondivers.

The sight of a diver’s head hitting the diving platform is something that sends shivers down the spines of all spectators. Surprisingly, serious injuries from such a mishap are few.

I would like to take the opportunity of mentioning the catastrophe that can occur when people, especially young people, dive into water whose depth they do not know. It takes 10 to 12 feet of water to prevent a serious head or neck injury occurring from striking the bottom of a pool or lake. In water less deep, the impact of a diver’s head on the bottom of the pool or lake can result in an injury that causes paralysis or death. I used to live near a river that was not deep. Every year, one or two divers sustained a paralyzing neck injury from jumping into the river from a height that imparted great force to the diver’s body.

DEAR DR. DONOHUE: Every time I think I am doing something good for myself, I find out I should probably be doing it differently or not at all.

I am a 58-year-old female. I walk a fast three miles at least five times a week. Several years ago I also started upper-body exercises with a 3-pound weight in each hand. I do approximately 20 to 25 repetitions of a number of exercises using these weights.

You wrote that “overload, a constant increase in the amount of weight lifted, is necessary to encourage bone and muscle growth.”

Have I not been producing desired effects by not increasing the weights, or did I misunderstand? – E.K.

You didn’t misunderstand. I could have been clearer in explaining overload.

Overload is something that bodybuilders and weightlifting athletes need to follow. You are getting a great deal of benefit from sticking with your program of 3-pound weights. You are not aiming to win the next Ms. America bodybuilding contest. You are, however, putting a stress on your muscles and bones, and that keeps them strong. Most importantly, it prevents osteoporosis.

Stick with your program as it is. I take my hat off to you.

DEAR DR. DONOHUE: I have twin boys, and both have epilepsy. They are on medicine for it and have not had a seizure in the past three years. They want to swim, but I have been afraid to let them do so. I worry about them having a seizure in deep water. Are my worries well-founded? – R.A.

Swimming and other water sports are fine for people who have good seizure control if some common-sense precautions are taken. Your boys should swim only when there is adequate supervision of swimmers – places where there are lifeguards. They shouldn’t swim in water that is opaque. The clear water of a swimming pool is a safe place. So are lakes and rivers if the water isn’t murky.

A wise step is to have them swim wearing a life preserver or some other flotation device.

DEAR DR. DONOHUE: Is it necessary to wait two full hours after eating before going swimming? – W.L.

If you are planning a long swim, then you should wait an hour or two for the stomach to at least partially empty before going in the water. Exercising muscles divert blood from the stomach, so food does not digest and you come down with cramps or diarrhea. If you want to cool off, a leisurely dip after a meal is safe.

DEAR DR. DONOHUE: When speaking of cancer, what do people mean when they say “metastasis”? Does it make the cancer diagnosis worse than usual? – A.M.

One attribute of cancer cells is their ability to break away from the original site of cancer and find their way to distant body sites. That is metastasis (muh-TASS-tuh-suss). Breast cancer, for example, can spread to bone. Metastasis is a sign of poor cancer control.

The cancer cells are carried to those distant sites either by way of the blood or by way of lymph fluid. Lymph fluid is the fluid that bathes all cells and brings them nutrition. It returns to the circulation through channels called lymphatics. Those channels pass through lymph nodes, and that is the reason lymph nodes are so frequently involved in cancer spread.

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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