What if Roger Clemens did use HGH? Well, it may not have helped him, anyway. Why? The hormone shots, which are used by some athletes to enhance performance, increase lean body mass and may not improve strength, according to a study in The Annals of Internal Medicine, which added that HGH may actually worsen exercise capacity and increase adverse events.

The study analyzed 44 previous studies in which 303 healthy people between 13 and 45 years old who took human growth hormone gained about 4.6 pounds, but that didn’t translate to either stronger biceps or quadriceps in the two longest studies that were examined. Yet, they were more likely to develop joint pain and carpal tunnel syndrome. Their ability to complete a bicycle race may have worsened and they had higher rates of fatigue. (Please see the discussion section in the study).

However, the analysis isn’t conclusive. The patients who were studied took lower HGH doses that many athletes, and the longest anyone was studied was 84 days. It’s also worth noting that many professional athletes mix HGH with anabolic steroids, which weren’t studied.

“We’re trying to paint a broad picture of outcomes,” Hau Liu, who led the team of researchers at Stanford University and Santa Clara Valley Medical Center in California, tells Bloomberg News. “If we ultimately want to answer questions about whether growth hormone or combinations of drugs help baseball players hit that home run, then we need to do more studies that closely mimic what athletes are doing.”