There is some national research that shows kids and human growth hormone are a bad mix. Some major sports stars like Roger Clemens, Barry Bonds and Miguel Tejada have been linked to HGH, but a new study shows the substance does almost nothing to help build your athletic stamina, in fact it may do just the opposite.

Most wellness directors say the only proven way to increase muscle strength is a good old-fashion workout and according to Stanford's Dr. Hau Liu Research, athletes who risk their careers by taking the banner human growth hormone might be better off it they didn't use it.

They found actually no evidence to support the motion the hormones improves athletic performance, if anything, they found there was a hint that HGH may actually worsen your exercise capacity.

The study's authors say it's almost impossible to conduct a study using the HGH doses that professional athletes may be taking because of ethical issues.