Physical activity is now considered one of the “big four” lifestyle factors (along with smoking, nutrition and drug abuse) that have major effects on health. In 2015, the Academy of Medical Royal Colleges put out a report summarizing the benefits of exercise, calling it both a “miracle cure” and a “wonder drug.” The report observes that regular exercise can prevent dementia, type 2 diabetes, some cancers, depression, heart disease and other common serious conditions — reducing the risk of each by at least 30%. This is better than many drugs.
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