This type of supplement appeals to a variety of people seeking to increase their strength. The supplement taken by the home-run king is a precursor for testosterone. Moreover, virtually no research has been done on their effects, although most experts believe that since the substances are anabolic steroid precursors, they present similar risks. That doesn't make taking it safe. Supplements that serve as precursors to testosterone pose particular risks in women and adolescents.
Women are likely to be more sensitive to the substances' virilizing effects.
Since teens are still developing, steroids can also cause premature closure of the growth plates, which would keep an adolescent fixed at his or her height. Finally, he says, these products are unregulated and don't necessarily contain what's on the label. We often see people trying to do excessive exercise immediately, and that can lead to injury. Two increasingly popular sports, biking and rollerblading, are shifting the types of injuries Dr. Grossman sees. The risk in both activities comes more from the environment than the exercise itself.