The motor proteins actin and myosin generate the forces exerted by contracting muscles. Current recommendations suggest that bodybuilders should consume 25–30% of protein per total calorie intake to further their goal of maintaining and improving their body composition. This is a widely debated topic, with many arguing that 1 gram of protein per pound of body weight per day is ideal, some suggesting that less is sufficient, while others recommending 1.5, 2, or more. It is believed that protein needs to be consumed frequently throughout the day, especially during/after a workout, and before sleep. There is also some debate concerning the best type of protein to take. Chicken, turkey, beef, pork, fish, eggs and dairy foods are high in protein, as are some nuts, seeds, beans, and lentils. Casein or whey are often used to supplement the diet with additional protein. Whey protein is the type of protein contained in many popular brands of protein supplements and is preferred by many bodybuilders because of its high Biological Value (BV) and quick absorption rates. Whey protein also has a bigger effect than casein on insulin levels, triggering about double the amount of insulin release. That effect is somewhat overcome by combining casein and whey. Bodybuilders are usually thought to require protein with a higher BV than that of soy, which is additionally avoided due to its claimed estrogenic properties. Still, some nutrition experts believe that soy, flax seeds and many other plants that contain the weak estrogen-like compounds or phytoestrogens, can be used beneficially, as phytoestrogens compete with estrogens for receptor sites in the male body and can block its actions. This can also include some inhibition of pituitary functions while stimulating the P450 system (the system that eliminates hormones, drugs and metabolic waste product from the body) in the liver to more actively process and excrete excess estrogen. Cortisol decreases amino acid uptake by muscle, and inhibits 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.
In the modern bodybuilding industry, the term "professional" generally means a bodybuilder who has won qualifying competitions as an amateur and has earned a "pro card" from their respective organization. Professionals earn the right to compete in competitions that include monetary prizes. A pro card also prohibits the athlete from competing in federations other than the one from which they have received the pro card. Depending on the level of success, these bodybuilders may receive monetary compensation from sponsors, much like athletes in other sports.
During the 1950s, the most successful and most famous competing bodybuilders[according to whom?] were Bill Pearl, Reg Park, Leroy Colbert, and Clarence Ross. Certain bodybuilders rose to fame thanks to the relatively new medium of television, as well as cinema. The most notable[according to whom?] were Jack LaLanne, Steve Reeves, Reg Park, and Mickey Hargitay. While there were well-known gyms throughout the country during the 1950s (such as Vince's Gym in North Hollywood, California and Vic Tanny's chain gyms), there were still segments of the United States that had no "hardcore" bodybuilding gyms until the advent of Gold's Gym in the mid-1960s. Finally, the famed Muscle Beach in Santa Monica continued its popularity as the place to be for witnessing acrobatic acts, feats of strength, and the like. The movement grew more in the 1960s with increased TV and movie exposure, as bodybuilders were typecast in popular shows and movies.
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.
Some Bodybuilders often split their food intake into 5 to 7 meals of equal nutritional content and eat at regular intervals (e.g. every 2 to 3 hours). This approach serves two purposes: to limit overindulging in the cutting phase, and to allow for the consumption of large volumes of food during the bulking phase. Eating more frequently does not increase basal metabolic rate when compared to 3 meals a day. While food does have a metabolic cost to digest, absorb, and store, called the thermic effect of food, it depends on the quantity and type of food, not how the food is spread across the meals of the day. Well-controlled studies using whole-body calorimetry and doubly labeled water have demonstrated that there is no metabolic advantage to eating more frequently.
Sandow was so successful at flexing and posing his physique that he later created several businesses around his fame, and was among the first to market products branded with his name. He was credited with inventing and selling the first exercise equipment for the masses: machined dumbbells, spring pulleys, and tension bands. Even his image was sold by the thousands in "cabinet cards" and other prints. Sandow was a perfect "Gracilian", a standard of ideal body proportions close to those of ancient Greek and Roman statues. Men's physiques were then judged by how closely they matched these proportions.