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.
exert. 1  to put forth or use energetically; put into action or use: to exert strength, influence, etc. 2  to apply (oneself) with great energy or straining effort.