Scientists in the U.S. say an athlete's ability to sweat may do more than keep the body cool but might also prevent the development of exercise-induced asthma (EIA).
EIA is a common respiratory condition among trained athletes and according to the researchers athletes with EIA produce less sweat, tears, and saliva than those who do not have breathing problems.
Lead study author Dr. Warren Lockette says it is unclear why so many elite athletes have exercise-induced asthma.
Dr. Lockette who is an advisor to the University of Michigan's NCAA Division I women's swimming team and has worked with many Olympians and future professional athletes with EIA, suggests it is possible that sufferers manifest symptoms of exercise-induced asthma simply because their levels of exertion and breathing rate are so high compared with the average, competitive sportsman.
Dr. Lockette, head of clinical research at San Diego Naval Medical Center and a former medical officer with the U.S. Navy, says a diagnosis of asthma would preclude many young sailors from becoming divers or special warfare operators.
He and a team of investigators wanted to understand the mechanisms by which asthma attacks are precipitated during exercise in otherwise healthy individuals.
Lockette and his colleagues analysed the relationship between fluid secretion rates, sweat, saliva and tears, in 56 athletic subjects suspected of having EIA. They measured the air movement through the lungs in the otherwise healthy volunteers before and after the administration of methacholine, a drug that can cause airways to constrict in patients with EIA.The researchers then measured responses to the application of pilocarpine, an agent used to induce sweating and saliva production.