The US FDA reports 50,000 health problems a year due to dietary supplements  and these often involve bodybuilding supplements. For example, the "natural" best-seller Craze, 2012's "New Supplement of the Year" by bodybuilding.com, widely sold in stores such as Walmart and Amazon, was found to contain N,alpha-Diethylphenylethylamine, a methamphetamine analog. Other products by Matt Cahill have contained dangerous substances causing blindness or liver damage, and experts say that Cahill is emblematic for the whole industry.
In males, testosterone is required for the development of male sex organs such as increased penis and testes size. The hormone also promotes the development of sexual male characteristics during puberty such as voice deepening and the growth of armpit, chest and pubic hair. Testosterone plays an important role in maintaining sex drive, sperm production, muscle strength and bone mass. A healthy level of testosterone is also protective against bone disorders such as osteoporosis.
After the ingestion of 5g creatine in otherwise healthy humans, serum levels of creatine were elevated from fasting levels (50-100µM) to 600-800µM within one hour after consumption. The receptor follows Michaelis-Menten kinetics with a Vmax obtained at concentrations higher than 0.3-0.4mmol/L, with prolonged serum concentrations above this amount exerting most of its saturation within two days.
Studies with animal and cellular models demonstrated positive effect of creatine ingestion on neurodegenerative diseases. These effects have been attributed to improved overall cellular bioenergetics due to an expansion of the phosphocreatine pool . Creatine deficiency syndromes, due to deficiency of glycine amidinotransferase and guanidinoacetate methyltransferase, can cause decreases or complete absence of creatine in the central nervous system. Syndromes of this nature have the possibility to be improved by supplementing orally with creatine. Brain creatine deficiency resulting from ineffective crea T1 has been shown not to be effectively treated with oral creatine supplementation . Additionally, oral creatine administration in patients with myopathies has shown conflicting results depending on the type of myopathy and creatine transport systems disorders .
It’s true—your genes can play a role when it comes to building muscle. In general, there are two types of muscle fibers: Type I, which are slow twitch, and Type II, which are fast twitch. Depending on which you have more of, you may have an easier or harder time gaining muscle. “Fast twitch muscle fibers are two times as thick as slow twitch muscle fibers, lending to the overall thickness of the muscle without any activity,” explains Lovitt. “Those people with a genetic predisposition of a high percentage of these fibers can increase muscle size very easily while the people with a higher percentage of slow twitch muscle fibers have to work really hard to put on mass.” It’s the reason why a world-class sprinter genetically has more fast twitch muscle fibers than a world-class marathoner—it comes down to what we’re born with.
Most people require around 20 calories per pound (or 44 kcal / kg) of bodyweight to gain muscle mass. Using a 180-pound (82kg) male as an example, the required daily calorie intake is 3600 calories (20 kcal x 180 lb = 3600 kcal). When it comes to gaining weight, it is likely that you may put on a few pounds of fat along the way, but if you do find your body fat increasing, either increase the amount of aerobic exercise (moderate intensity) you are doing or slightly reduce the total number of calories you are consuming. Remember you can’t force feed muscle gain!
Heath has 1.8 million Instagram followers, 300,000 Twitter followers, a global fan base and a growing portfolio of muscle magazine covers. He competes in just one competition a year, Mr. Olympia, for which he won the $400,000 first prize this year. He spends the rest of the year staying in shape and flying hundreds of thousands of miles for appearances, conferences and meetings. He has five sponsors, led by Ultimate Nutrition, a supplement company. All told, he earns more than $1 million a year, his agent said.
Testosterone is necessary for normal sperm development. It activates genes in Sertoli cells, which promote differentiation of spermatogonia. It regulates acute HPA (hypothalamic–pituitary–adrenal axis) response under dominance challenge. Androgen including testosterone enhances muscle growth. Testosterone also regulates the population of thromboxane A2 receptors on megakaryocytes and platelets and hence platelet aggregation in humans.
Recently, studies are coming out that show a general decline in testosterone levels of men in the United States and around the world. The trend is across the board and doesn’t appear to be caused simply by a decline in health, aging or an increase in obesity rates. It could be caused because of chemicals or environmental factors. In any case, low levels of testosterone can affect many areas of your health, including your ability to build muscle. If you suspect that you have low testosterone levels, you can ask your doctor to test you for it. In addition to traditional hormone therapies, there are also many natural ways to boost your levels including through supplements, some of which will be discussed later in this article.
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.