To combat steroid use and in the hopes of becoming a member of the IOC, the IFBB introduced doping tests for both steroids and other banned substances. Although doping tests occurred, the majority of professional bodybuilders still used anabolic steroids for competition. During the 1970s, the use of anabolic steroids was openly discussed, partly due to the fact they were legal. In the Anabolic Steroid Control Act of 1990, U.S. Congress placed anabolic steroids into Schedule III of the Controlled Substances Act (CSA). In Canada, steroids are listed under Schedule IV of the Controlled Drugs and Substances Act, enacted by the federal Parliament in 1996.
The high levels of muscle growth and repair achieved by bodybuilders require a specialized diet. Generally speaking, bodybuilders require more calories than the average person of the same weight to provide the protein and energy requirements needed to support their training and increase muscle mass. In preparation of a contest, a sub-maintenance level of food energy is combined with cardiovascular exercise to lose body fat. Proteins, carbohydrates and fats are the three major macronutrients that the human body needs in order to build muscle. The ratios of calories from carbohydrates, proteins, and fats vary depending on the goals of the bodybuilder.
Site enhancement oil, often called "santol" or "synthol" (no relation to the Synthol mouthwash brand), refers to oils injected into muscles to increase the size or change the shape. Some bodybuilders, particularly at the professional level, inject their muscles with such mixtures to mimic the appearance of developed muscle where it may otherwise be disproportionate or lacking. This is known as "fluffing". Synthol is 85% oil, 7.5% lidocaine, and 7.5% alcohol. It is not restricted, and many brands are available on the Internet. The use of injected oil to enhance muscle appearance is common among bodybuilders, despite the fact that synthol can cause pulmonary embolisms, nerve damage, infections, sclerosing lipogranuloma, stroke, and the formation of oil-filled granulomas, cysts or ulcers in the muscle. Rare cases might require surgical intervention to avoid further damage to the muscle and/or to prevent loss of life.
The important role of nutrition in building muscle and losing fat means bodybuilders may consume a wide variety of dietary supplements. Various products are used in an attempt to augment muscle size, increase the rate of fat loss, improve joint health, increase natural testosterone production, enhance training performance and prevent potential nutrient deficiencies.
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.
The bulking and cutting strategy is effective because there is a well-established link between muscle hypertrophy and being in a state of positive energy balance. A sustained period of caloric surplus will allow the athlete to gain more fat-free mass than they could otherwise gain under eucaloric conditions. Some gain in fat mass is expected, which athletes seek to oxidize in a cutting period while maintaining as much lean mass as possible.
An article by Muscle & Fitness magazine, "Overtrain for Big Gains", claimed that overtraining for a brief period can be beneficial. Overtraining can be used advantageously, as when a bodybuilder is purposely overtrained for a brief period of time to super compensate during a regeneration phase. These are known as "shock micro-cycles" and were a key training technique used by Soviet athletes.
Bodybuilding developed in the late 19th century, promoted in England by German Eugen Sandow, now considered as the "Father of Bodybuilding". He allowed audiences to enjoy viewing his physique in "muscle display performances". Although audiences were thrilled to see a well-developed physique, the men simply displayed their bodies as part of strength demonstrations or wrestling matches. Sandow had a stage show built around these displays through his manager, Florenz Ziegfeld. The Oscar-winning 1936 musical film The Great Ziegfeld depicts the beginning of modern bodybuilding, when Sandow began to display his body for carnivals.