In the last week leading up to a contest, bodybuilders usually decrease their consumption of water, sodium, and carbohydrates, the former two to alter how water is retained by the body and the latter to reduce glycogen in the muscle. The day before the show, water is removed from the diet, and diuretics may be introduced, while carbohydrate loading is undertaken to increase the size of the muscles through replenishment of their glycogen. The goal is to maximize leanness and increase the visibility of veins, or "vascularity". The muscular definition and vascularity are further enhanced immediately before appearing on stage by darkening the skin through tanning products and applying oils to the skin to increase shine. Some competitors will eat sugar-rich foods to increase the visibility of their veins. A final step, called "pumping", consists in performing exercises with light weights or other kinds of low resistance (for instance two athletes can "pump" each other by holding a towel and pulling in turn), just before the contest, to fill the muscles with blood and further increase their size and density.
Weight training aims to build muscle by prompting two different types of hypertrophy: sarcoplasmic and myofibrillar. Sarcoplasmic hypertrophy leads to larger muscles and so is favored by bodybuilders more than myofibrillar hypertrophy, which builds athletic strength. Sarcoplasmic hypertrophy is triggered by increasing repetitions, whereas myofibrillar hypertrophy is triggered by lifting heavier weight. In either case, there is an increase in both size and strength of the muscles (compared to what happens if that same individual does not lift weights at all), however, the emphasis is different.
The general strategy adopted by most present-day competitive bodybuilders is to make muscle gains for most of the year (known as the "off-season") and, approximately 12–14 weeks from competition, lose a maximum of body fat (referred to as "cutting") while preserving as much muscular mass as possible. The bulking phase entails remaining in a net positive energy balance (calorie surplus). The amount of a surplus in which a person remains is based on the person's goals, as a bigger surplus and longer bulking phase will create more fat tissue. The surplus of calories relative to one's energy balance will ensure that muscles remain in a state of anabolism.
Comer has an athletic build that comes from years of martial arts and marathon training, not to mention amateur competitive bodybuilding, activities that have taken a toll on her now bandaged 40-something-year-old knees. — Quanta Magazine, "The Art of Teaching Math and Science," 16 June 2019 Teresa Giudice, who's best known as a personality on Bravo's Real Housewives of New Jersey, competed in her first bodybuilding contest Saturday. — Carly Mallenbaum, USA TODAY, "'Real Housewives' star Teresa Giudice shows off new muscles at bodybuilding competition," 10 June 2018 His first wife, Sitora Yusufiy, suggested in an interview with Time magazine, with little evidence other than his penchant for bodybuilding and mirror-gazing, that Omar Mateen could have been gay. — Tim Fitzsimons /, NBC News, "What really happened that night at Pulse," 12 June 2018 The physique competition will be held at McGlohon Theater and includes the following categories: bodybuilding, fitness, men’s physique, figure, bikini, classic physique and women’s physique. — Courtney Devores, charlotteobserver, "Your 5-minute guide to the best things to do in Charlotte | June 22-28," 21 June 2018 Fans who have been following Giudice closely on social media have watched the reality star workout in videos, but Giudice hasn't posted publicly about her first bodybuilding competition. — Carly Mallenbaum, USA TODAY, "'Real Housewives' star Teresa Giudice shows off new muscles at bodybuilding competition," 10 June 2018 Carolyn Marvin, who served as the graduate adviser for both Prosper and Nirenberg, pointed to his thesis, an autoethnography about the subculture of bodybuilding. — Josh Baugh, San Antonio Express-News, "Nirenberg knew immediately that he’d eventually marry Erika Prosper," 17 Mar. 2018 The bodybuilding competition is one of two hosted produced each year in Louisville by Kentucky Muscle promoter Brent L. Jones. — Matt Stone, The Courier-Journal, "Bodybuilders, fitness athletes go flex at 2018 KDF Derby Championships," 29 Apr. 2018 Father John Brown is basically a bodybuilding legend, having won two Mr. Universe titles and three Mr. World crowns. — Jr Radcliffe, Milwaukee Journal Sentinel, "Facts you may have missed about each Packers draft choice in 2018," 4 May 2018
Some bodybuilders use drugs such as anabolic steroids and precursor substances such as prohormones to increase muscle hypertrophy. Anabolic steroids cause hypertrophy of both types (I and II) of muscle fibers, likely caused by an increased synthesis of muscle proteins. They also provoke undesired side effects including hepatotoxicity, gynecomastia, acne, the early onset of male pattern baldness and a decline in the body's own testosterone production, which can cause testicular atrophy. Other performance-enhancing substances used by competitive bodybuilders include human growth hormone (HGH), which can cause acromegaly.
Although muscle stimulation occurs in the gym (or home gym) when lifting weights, muscle growth occurs afterward during rest periods. Without adequate rest and sleep (6 to 8 hours), muscles do not have an opportunity to recover and grow. Additionally, many athletes find that a daytime nap further increases their body's ability to recover from training and build muscles. Some bodybuilders add a massage at the end of each workout to their routine as a method of recovering.
Bodybuilding became more popular in the 1950s and 1960s with the emergence of strength and gymnastics champions, and the simultaneous popularization of bodybuilding magazines, training principles, nutrition for bulking up and cutting down, the use of protein and other food supplements, and the opportunity to enter physique contests. The number of bodybuilding organizations grew, and most notably the International Federation of Bodybuilders (IFBB) was founded in 1946 by Canadian brothers Joe and Ben Weider. Other bodybuilding organizations included the Amateur Athletic Union (AAU), National Amateur Bodybuilding Association (NABBA), and the World Bodybuilding Guild (WBBG). Consequently, the male-dominated contests grew both in number and in size. Besides the many "Mr. XXX" (insert town, city, state, or region) championships, the most prestigious titles[according to whom?] were Mr. America, Mr. World, Mr. Universe, Mr. Galaxy, and ultimately Mr. Olympia, which was started in 1965 by the IFBB and is now considered the most important bodybuilding competition in the world.