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Q. Are Salt Pills Needed?

I am a 53-year-old slow, beginner runner doing about 15 miles a week at a run/wall pace. I also bicycle two hours a week on hilly terrain and practice Yoga daily.

For years I took salt pills during the summer when I was exercising to avoid too much fluid and sodium loss. Everything published today seems to make salt into the enemy We are urged to limit our intake. However, the amount of salt I lose through perspiration must be enormous, especially during hot weather. Doesn't it make more sense to supplement sodium rather than limit consumption? Are we being hoodwinked into yet another fad that could have negative consequences because the information was dumbed-down to include everyone when it was oaly relevant to a few? I can barely practice Yoga without a foot or leg cramp. Should warnings about salt be modified for people who exercise heavily enough to sweat for an hour or more a day?

Jan Gleason

Bainbridge Island, WA

A. First, readers should take what is printed in the media with a grain of salt--no pun intended. Often reporters will take one bit of information and blow it out of proportion to make the story fit what they think the readers want to hear. Research results are often printed in scientific journals as preliminary, and are speculative, raising more questions for investigators. Reporters take the information as the final word, and run with it. Researchers are often dismayed at how the media will take their work and report it to meet their needs. It is usually not the research, but how the reports are presented to the public that causes problems. It is no wonder that consumers are confused.

It may seem that you are losing a lot of sodium in your sweat, but you are losing far less than your body has stored. Your sweat also contains other minerals, such as potassium, that give it a salty taste. When you exercise, the amount of sodium in your blood increases as you lose water. Salt tablets should not be a consideration as they tend to draw water out of your cells and into your gut, making the situation worse, not better. Your body's electrolyte balance and ability to cool itself can then become impaired.

The athletes who must be most concerned about sodium losses are those who exercise for more than four hours in extreme heat. Triathletes competing at the Iron Man level and marathoners whose times are in the four to six hour range are examples of athletes who may need to be cautious. One reason these individuals are at risk is because they tend to over-compensate for fluid losses with plain water, which can cause metabolic imbalances.

Athletes who eat a lower salt diet actually have less sodium in their sweat. If you are noticing excessive saltiness in yours, it may be that you are consuming more sodium than you need. The kidneys and sweat glands conserve salt when it is in short supply, protecting you from becoming salt depleted. Only when water intake becomes excessive is inadequate sodium a potential problem with athletes. You will also tend to have a saltier sweat at the beginning of the summer when the weather first heats up. When your body becomes acclimated to the warmer temperatures, the amount of salt in your sweat decreases.

The average American diet contains as much as three times the amount of sodium that a healthy person needs. Some reports state that we consume as much as six times our need. People who tend to eat processed foods and eat out a lot tend to have the highest consumption. Believe it or not, most people do not use the salt shaker any longer, but still get too much sodium because they eat boxed, bagged and packaged foods that are preserved and flavored with large amounts of sodium.

If you are concerned about your sodium intake, consuming four to six ounces of a sports drink such as Gatorade every 10 to 20 minutes is enough to replenish your need for sodium. All things considered, your muscle cramping is likely to be caused by muscle fatigue rather than salt depletion and you should be advised against taking salt tables.

Sarab Harding Laidlaw, M.S., R.d

Glade Park, CO

Q. Sleepy Feet: Disturbance or Disability

I am training for my third marathon this year. In an effort to finish it in four hours, I've increased my weekly distance and my speed work. For the past two months, my right foot will occasionally fall asleep around the fourth mile in tempo runs. By changing my gait or slowing down, I can "wake it up" in a few miles. Or, if it is a shorter run, simply finish at mile six. I am concerned that I might be doing permanent damage, and at the least, it's disturbing. It seems to happen when I'm running well with an above average pace.

I had a similar problem a few years ago, but in both feet. Someone suggested I loosen my shoelaces and that helped. This time around, if I loosen my laces any more my shoes will fly off.

Edward R. H. McDowell, Jr.

Bellaire, TX

A. Damage or compression to the nerves or blood vessels can cause numbness in the foot or part of the foot. Unless there is compression from laces, constricting socks, or pressure points from the shoe, the numbness is probably not from the blood vessels, but from the nerves. This could be pressure on the local area such as numbness between the third and fourth toes from a Morton's neuroma. Numbness can occur at different parts of the foot depending on the source of the pressure such as along the arch and inside of the ankle from tarsal tunnel syndrome. If the whole foot goes numb there could be compression on the nerves of the back, such as a compressed disc, sciatic nerve impingement, or pressure over the nerve behind the knee.

If the numbness goes away with a tingling sensation returning, it is nerve related. If the numbness goes away with a throbbing feeling, it is vascular. In either case, once you find the source of the problem it can be corrected. Remember that the feet swell with sustained running, so make sure your shoes are wide enough. Consider elastic shoelaces and different lacing patterns.

Jack Daniels, Ph.D.

Cortland, NY

A. Other possibilities include vascular blockage of the femoral artery or its smaller branches causing loss of nerve function. Also, foot or leg compartment syndrome with internal swelling can cause nerve pressure and loss of function. There are systemic diseases like diabetes that are associated with peripheral neurological loss. It would be reasonable to get a thorough check up to rule out more serious problems. Assuming you are healthy, a sports medicine professional can help locate the source of the irritation and correct it.

Marvin Bloom, M.D.

Burlingame, CA

Q. Coumadin Effect on Running

I am 59-year-old and a very active runner. Over the past 20 years I have run 147 marathons, 139 triathlons, four Iron Mans, and five ultra-marathons. During 1988 I won eight out of 20 triathlons in my age division. I really love competition and long-distance running. About nine months ago I was diagnosed with atrial fibrillation and now use Coumadin. Fortunately, I have continued to run and race. Can you give me more information about Coumadin use, atrial fibrillation, and their effect on running performance?

Terry Lee Ives

San Clemente, CA

A. Atrial fibrillation is an irregular beating of the heart. It occurs when the upper two cardiac chambers, instead of beating synchronously with the lower chambers, fibrillate. Fibrillation is chaotic electrical activity and does not allow normal synchronized contraction of the upper (atrial) heart chambers. This can occur in an otherwise normal heart, in which case the diagnosis is called lone atrial fibrillation, and in that setting, patients do not need to be put on an anticoagulant such as Coumadin, because they do not have an increased risk of stroke.

Patients, however, who have atrial fibrillation in the setting of hypertension, an overactive thyroid, valvular heart disease or coronary artery disease, do require anticoagulation to prevent the occurrence of a stroke. A stroke occurs in atrial fibrillation because blood can pool in the upper chambers and form clots. These can occasionally break free and go to the other parts of the body. When they go to the brain, the result is a stroke. The annual incidence of stroke in atrial fibrillation is about 5%. When patients are treated with Coumadin, this risk is reduced to 1%.

The main worry with anticoagulation is the potential for bleeding, but this is an acceptable risk, since without treatment you have a one in four chance of having a stroke in five years. When a patient is on Coumadin therapy, his anticoagulation status is carefully monitored with a blood test called a protime or INR. The test checks to make sure you are anti-coagulated in the correct therapeutic range to prevent strokes. If the blood is too thin, then there is an increased risk of bleeding. If the blood is not thin enough, then there is the risk of forming a blood clot and suffering a stroke.

The other problem with atrial fibrillation is a heart rate, which is often too rapid. However, patients such as yourself who are fit usually have increased vagal tone and may not require drugs to slow the heart. Sometimes treatment is given to try to convert the heart rhythm to normal with medications or electrical shock, or other newer types of therapy. Treatment may or may not be successful for a variety of reasons. You should be evaluated thoroughly by a sports-oriented cardiologist if you haven't already done so, but an internist can monitor your care once a treatment plan is in place. The good news is that your treatment should not interfere with your running.

Bernard Gitler, M.D.

New Rochelle, NY

A. Coumadin has side effects with potential bleeding complications and can be somewhat hazardous given some of your past activities such as Iron Mans or ultra-marathons, especially where difficult terrain is encountered. Your risk of injury increases with rugged terrain and access to emergency medical aid could be restricted in remote areas. You should be extremely aware of the potential for excessive bleeding when taking an anticoagulant like Coumadin. Running per se is not necessarily a problem, but the risk of bleeding as the result of an injury is potentially serious.

Anthony P. Goldman, M.D.

Tampa, FL

A. Deciding on medical treatment is often a matter of balancing risk factors. This is true in the case of Coumadin for use in reducing the risk of stroke. Research shows that there is a group of patients who are at relatively low risk of stroke and these patients can probably be treated with aspirin rather than Coumadin, to avoid the risk of bleeding associated with that drug. On the other hand patients with prior transient ischemic attack or stroke, hypertension, congestive heart failure, reduced left ventricular function, and women over the age of 75 are at higher risk of stroke. Generally they should be treated with Coumadin since their risk of stroke exceeds any risk of taking Coumadin. The risk of major bleeding with Coumadin use averages about 2% per year. If your risk of stroke is not higher than that, then aspirin might be an adequate treatment. Your cardiologist will take all relevant factors into consideration in determining whether the risks associated with Coumadin are justified in your case.

Todd D. Miller, M.D.

Rochester, MN

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