Muscle growth is more difficult to achieve in older adults than younger adults because of biological aging, which leads to many metabolic changes detrimental to muscle growth; for instance, by diminishing growth hormone and testosterone levels. Some recent clinical studies have shown that low-dose HGH treatment for adults with HGH deficiency changes the body composition by increasing muscle mass, decreasing fat mass, increasing bone density and muscle strength, improves cardiovascular parameters, and affects the quality of life without significant side effects.[unreliable medical source?]
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.
In the 1970s, bodybuilding had major publicity thanks to the appearance of Arnold Schwarzenegger, Franco Columbu, Lou Ferrigno, and others in the 1977 docudrama Pumping Iron. By this time, the IFBB dominated the competitive bodybuilding landscape and the Amateur Athletic Union (AAU) took a back seat. The National Physique Committee (NPC) was formed in 1981 by Jim Manion, who had just stepped down as chairman of the AAU Physique Committee. The NPC has gone on to become the most successful bodybuilding organization in America and is the amateur division of the IFBB. The late 1980s and early 1990s saw the decline of AAU-sponsored bodybuilding contests. In 1999, the AAU voted to discontinue its bodybuilding events.
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.
Carbohydrates play an important role for bodybuilders. They give the body energy to deal with the rigors of training and recovery. Carbohydrates also promote secretion of insulin, a hormone enabling cells to get the glucose they need. Insulin also carries amino acids into cells and promotes protein synthesis. Insulin has steroid-like effects in terms of muscle gains. It is impossible to promote protein synthesis without the existence of insulin, which means that without ingesting carbohydrates or protein—which also induces the release of insulin—it is impossible to add muscle mass. Bodybuilders seek out low-glycemic polysaccharides and other slowly digesting carbohydrates, which release energy in a more stable fashion than high-glycemic sugars and starches. This is important as high-glycemic carbohydrates cause a sharp insulin response, which places the body in a state where it is likely to store additional food energy as fat. However, bodybuilders frequently do ingest some quickly digesting sugars (often in form of pure dextrose or maltodextrin) just before, during, and/or just after a workout. This may help to replenish glycogen stored within the muscle, and to stimulate muscle protein synthesis.
In natural contests, the testing protocol ranges among organizations from lie detectors to urinalysis. Penalties also range from organization to organization from suspensions to strict bans from competition. It is also important to note that natural organizations also have their own list of banned substances and it is important to refer to each organization's website for more information about which substances are banned from competition. There are many natural bodybuilding organizations; some of the larger ones include: MuscleMania, Ultimate Fitness Events (UFE), INBF/WNBF, and INBA/PNBA. These organizations either have an American or worldwide presence and are not limited to the country in which they are headquartered.
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 The winner of the annual IFBB Mr. Olympia contest is generally recognized as the world's top male professional bodybuilder. Since 1950, the NABBA Universe Championships have been considered the top amateur bodybuilding contests, with notable winners such as Reg Park, Lee Priest, Steve Reeves, and Arnold Schwarzenegger. Winners generally go on to become professional athletes.