Bodybuilding is the use of progressive resistance exercise to build, control, and develop one's muscles via hypertrophy. An individual who engages in this activity is referred to as a bodybuilder. It is primarily undertaken for aesthetic purposes over functional ones, distinguishing it from similar activities such as powerlifting, which focuses solely on gaining physical strength.
In professional bodybuilding, competitors appear onstage in line-ups and perform specified poses (and later individual posing routines) for a panel of judges who rank them based on conditioning, muscularity, posing, size, stage presentation, and symmetry. Bodybuilders prepare for competitions by eliminating non-essential body fat, which is enhanced at the final stage by a combination of carbohydrate loading and dehydration to achieve maximum muscle definition and vascularity; they also get heavily tanned and shave their bodies to accentuate the contrast of their skin against the stage lights.