Bodybuilding Supplement - Testosterone Boosters

Testosterone Boosters

There are several naturally occurring plants and vitamins as well as synthetic chemicals that supplement companies claim may produce an increase in testosterone levels. However, the effectiveness of many of these products is questionable due to a lack of valid scientific testing. Some commonly taken supplements of this type are ZMA and Tribulus terrestris.

In a placebo-controlled study, published in the British Journal of Sports Medicine, a statistically significant increase in strength and arm circumference was achieved with an extract of Eurycoma longifolia. In another study on male rats, Eurycoma longifolia extract at the highest administered dosage resulted in an increase in size of a muscle (the levator ani) of about 20 percent over controls. A 2008 study concluded that Eurycoma longifolia is capable of suppressing estrogens which are potent inhibitors of testosterone production.