Canadian swimmer Catherine Garceau won a Bronze medal for synchronized swimming in 2000, but in her forthcoming memoir "Heart of Bronze," she describes why she's currently out of the pool--she attributes a number of health problems, including chronic bronchitis and frequent migraines, to her continuous exposure to the high levels of chlorine found in indoor swimming pools.
Dr. Alfred Bernard is a professor of toxicology at the Catholic University of Louvain in Brussels and one of the world's leading researchers on aquatic environments. He has published a series of studies documenting the effects of chlorine and its byproducts in swimming pools.
In June, Bernard published a study in the International Journal of Andrology linking chlorine with testicular damage. Swimming in indoor, chlorinated pools during childhood was shown to reduce levels of serum inhibin B and total testosterone, both indicators of sperm count and mobility. Bernard notes in the study summary that the "highly permeable scrotum" allows chlorine to be absorbed into the body.
Bernard has also substantiated previous studies' claims of a link between swimming in indoor chlorinated pools and the development of asthma and recurrent bronchitis in children. His 2007 study showed airway and lung permeability changes in children who had participated in an infant swimming group.
Reading these studies, it's easy to forget that swimming itself is a great aerobic exercise that puts less stress on your joints than activities like running. In fact, it's a sport often recommended for children with asthma because the humid, moist environment makes it easier for athletes to inhale and the breathing techniques can improve lung function.
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