Body building is the use of progressive resistance exercise to control and develop one's musculature for aesthetic purposes. An individual who engages in this activity is referred to as a body builder. In competitive body building, body builders appear in lineups and perform specified poses (and later individual posing routines) for a panel of judges who rank the competitors based on criteria such as symmetry, muscularity, and conditioning. Body builders prepare for competitions through the elimination of nonessential body fat, enhanced at the last stage by a combination of extracellular dehydration and carbohydrate loading, to achieve maximum muscular definition and vascularity, as well as tanning to accentuate the contrast of the skin under the spotlights. Body builders may use anabolic steroids and other performance-enhancing drugs to build muscles.
The winner of the annual IFBB Mr. Olympia contest is generally recognized as the world's top male professional body builder. Since 1950, the NABBA Universe Championships have been considered the top amateur body building contests, with notable winners such as Reg Park, Lee Priest, Steve Reeves, and Arnold Schwarzenegger. Winners generally go on to become professional athletes.