Effects of Performance-Enhancing Drugs May Last for Decades

Doping has tarnished the image of many sports in recent years, from track and field to baseball and cycling. With every revelation that another athlete was caught using performance-enhancing drugs, years-long bans are issued and officials vow to crack down harder next time. But according to recent research, the only way to ensure a level playing field may be decades-long bans.

Physiologists from the University of Oslo in Norway have been studying the effects of anabolic steroids in mice, and their findings suggest that the boost the substances give to muscles could last for decades. The substances appear to give muscles a sort of memory that allows them to bulk up rapidly when stressed even long after they’ve been withdrawn.

Clay Hensley
Pitcher Clay Hensley was suspended for 15 games in 2005 for steroid use while in the minor leagues.

In a study, researchers gave female mice an anabolic steroid, testosterone propionate, for 14 days. In that time, the mice’s muscles bulked up significantly, adding 77% more girth and 66% more myonuclei. After the steroids were withdrawn for three months (about 10% of the mouse’s lifespan), the mice’s muscles lost bulk but not myonuclei. The researchers then started the mice on an intensive exercise regimen for six days, though this time without any steroids. Non-doped mice didn’t see their muscles grow significantly in that time, but the formerly ’roided mice added 31% more cross-sectional muscle area.

That anabolic steroids can affect muscle building long after their use suggests that two- to four-year doping bans are too short to be effective, said Kristian Gundersen, one of the study’s authors, in an interview with BBC Sport. He said the relevant studies still need to be performed in humans, but he’s confident in the applicability of his findings.

Tom Fordyce, reporting for BBC Sport:

[Gundersen] is convinced both that the same mechanism is at work in human muscles and that other performance-enhancing drugs would have similar long-term benefits.

He said: “I would be very surprised if there were any major differences between humans and mice in this context.

“The fundamental biology of muscle growth is similar in humans and in mice, and in principle any drug that builds muscle mass could trigger this mechanism.”

Whether this triggers a change in doping-bans remains to be seen. In the meantime, the research offers some advice for non-athletes: Strength training while young can pay dividends as we age, according to Gundersen and his team. As we age, our ability to generate new myonuclei wanes, so building up a healthy stock early in life could help us remain strong well into retirement.