For generations, parents have cautioned their children against swimming for an hour after eating – the common explanation being that the stomach is unable to cope with digesting food and the exertion of swimming at the same time, leading to stomach cramps that can cause the child to struggle in the water and drown. It sounds vaguely plausible, and back in the 1960s the American Red Cross advised against swimming straight after eating. Yet even at the time, there were suspicions it was nonsense.
In the late 1960s, several scientific studies took place in which swimmers were given meals at different times before going for a dip. They found no evidence of cramps. A few reported nausea and regurgitation, but nothing likely to prove life-threatening.
In 2005, researchers in Australia found evidence that swimmers may increase their risk of experiencing a stitch if exercising fewer than two hours after a big meal, but there was no evidence of a major threat to health.
In 2011, a review by an advisory panel of the American Red Cross of all the scientific evidence found that there is nothing to suggest that eating before swimming constitutes a risk of drowning, and concluded that the link “can be dismissed as a myth”.
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