Immune System Protection for Athletes

Since the late '70s, numerous studies involving competitive athletes from different sports have documented that heavy athletic training can increase the risk of catching colds and flu.

Meanwhile, studies have also found that moderate exercise decreases the risk of upper respiratory tract infections and shortens the duration and severity of symptoms should the exerciser catch a cold or flu.

What's an athlete to do? Moderate intensity training will not get them the gold medal. They have to train hard to make it to first place.

How much training pushes an athlete over the edge depends on the athlete's current state of health, nutrition, stress and sleep patterns.

A study titled "Exercise, Immunity and Susceptibility to Infection" that was published in the 1999 Physician and Sports Medicine Journal (PSMJ) also pointed out that athletes face situations not usually experienced by regular exercisers, which makes them more vulnerable to infections.

Since they compete in many different local and international competitions, athletes are exposed to a greater range of infected persons and unfamiliar microorganisms.

They also have to contend with environmental stressors that adversely affect the immune system like extreme cold or heat, pollution, high altitudes, travel fatigue, jet lag and sleep deprivation (especially during long and demanding events like the Tour de France).

Not only do athletes have to deal with the psychological pressure of competition but just being in a strange environment can also trigger mental and emotional stress, which in turn can affect the immune system.

Clearly, athletes have to take extraordinary measures to protect their health. Here are recommendations based on the PSMJ study and other research.

Minimize Exposure
Avoid close contact with people who have a cold before, during and after competition. Wash hands carefully before meals and avoid rubbing the eyes or nose with unwashed hands.

Warning signs of Overtraining
Classic symptoms are sleeplessness, excessive fatigue, chronic muscle soreness, declining performance levels, moodiness, increased resting heart rate, irritability, inability to concentrate, constant colds and flu.

Keep a Training Log
Keeping a detailed record of training volume and intensity as well as documenting any physical and psychological symptoms will help athletes and their coaches walk the tightrope between training hard and overtraining.

Athletes need to realize that life-related stressors like marital problems and job anxieties coupled with intense training schedules can make them more prone to infections.

During prolonged periods of mental and emotional stress, training intensity may need to be lowered. Having a mentor or close friend to talk to can help reduce stress levels even if the situation causing the stress is still there. Athletes can be so focused on their goals that they don't make time for close social contact.

Consider Immunotherapy
The scientists behind the PSMJ study recommend that athletes with a low level of serum immunoglobulins be given monthly injections of human immunoglobulins to reduce the severity of any contracted disease.

They also suggest that all athletes competing internationally should be inoculated against whatever virus is prevalent in that area.

Another suggestion from a different study is that athletes should consider getting the flu vaccine, which will protect them from 90 different types of flu for 12 months. Take note that this will not protect an athlete from SARS but will at least prevent unnecessary downtime from catching ordinary flu.

Avoid Very Low-Fat Diets
A University of Buffalo study presented at the 1999 International Society for Exercise and Immunology Symposium reported that low-fat diets (17 percent fat) weakened the immune system of runners compared to medium-and high-fat diets (32 percent and 41 percent, respectively).

The study was done on male and female competitive runners who trained 40 miles a week. They followed their normal diets for one month, and then did one month each of the low, moderate, and high-fat diets. In all cases, protein was kept to 15 percent and carbohydrates made up the difference.

The study found that levels of natural killer cells were more than double when the athletes were on higher-fat diets compared to low-fat diets. A previous study by the same university found that runners had better endurance and performance with higher fat percentages in their diet.

Eat Properly
Common nutritional deficiencies that have been reported include essential fatty acids, folic acid, Vitamins B6, C, and E.

A multivitamin containing the minerals zinc and selenium are a relatively cheap form of insurance for the immune system but athletes (and everyone else for that matter) should aim to get the bulk of their vitamins, minerals, and phytochemicals from real food the way nature intended.

Ideally, an athlete's diet should be under the supervision of an experienced sports nutrition dietician.

Athletes can be just as tempted to go on a crash diet as regular exercisers especially after the off-season when lack of exercise and a relaxation of dietary discipline can lead to weight gain.

The American Council on Exercise says low-calorie diets, long-term fasting, and rapid weight loss have been shown to impair immune function. The ACE further adds that losing weight while training heavily is not good for the immune system.

I know of a female competitive body builder who was constantly coming down with colds and flu because she was training hard and dieting drastically.

Eventually, she came down with pneumonia. Her immune system was so worn-out that it took several months for her to fully recover. Ironically, she was strong on the outside but weak on the inside.

Know When to Stop Training
Athletes and coaches should learn to distinguish between above-the-neck and below-the-neck symptoms of colds and flu.

An athlete can still train with a stuffy nose by lowering training intensity and taking a non-drowsy decongestant during the day and an antihistamine at night.

However, if the athlete has a cough, fever, chills, joint and muscle aches, swollen lymph nodes, vomiting or diarrhea, training should be stopped until the symptoms have disappeared. Some experts recommend waiting for two weeks before training is continued.

Training with systemic or below-the-neck symptoms can cause serious medical problems and a rare but possible danger is dying from a cardiac arrest during exercise due to viral myocarditis (viral inflammation of the heart muscle).

Getting enough rest and sleep are extremely important to an athlete's immune system as well as his or her quality of performance. Infection-fighting cells are markedly affected by even one night of lack of sleep.

The body needs time to recover from the intensity of hard training. The harder you train, the more sleep and rest you need to recover. Alternate between light and heavy days of training. Have at least one full rest day a week.

Don't burn the candle on both ends by training hard during the day and then partying the night away. Teenage athletes, especially, are prone to thinking they are invincible because of the seemingly boundless energy their youth has bestowed upon them.

Consider Changing Time of Training
A study published this year in the British Journal of Sports Medicine found that early morning might not be the best time for athletes to do heavy training if they have just recovered from an illness or injury or they are feeling rundown.

Researchers found that cortisol levels are naturally at their highest in the morning while immunoglobulin A (IgA) levels are at their lowest. Cortisol is a stress hormone that is known to be an immune system suppressor while IgA, a chemical found in saliva and mucus, destroys airborne viruses and bacteria.

Under the circumstances mentioned above, heavy early morning workouts can make athletes more vulnerable to infectious diseases.

The study findings should not be applied to the average exerciser who works out in the early morning because other studies have found that moderate exercise increases or has no effect on IgA levels.

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