But it must be understood, that unless designed otherwise, i.e. unless the Units of Analysis are chosen from all people, most studies are generalizable only for a much narrower population of the people w/in a nation, region, city, etc.
exercising - the activity of exerting your muscles in various ways to keep fit; the doctor recommended regular exercise; he did some exercising; the physical exertion required by his work kept him fit. exercise, physical exercise, physical exertion, workout.
Swimmers usually refer to taper and shave, which is a strategy used in the days immediately preceding a big competition. Tapering refers to rest from training, and coaches still disagree about how effective this is. And although shaving is more or less scientifically proven to be effective, it isn't without controversy.