Petersenâ€™s donor was a fellow elite cyclist, and after analyzing the sample and those of other riders, she discovered an unusually high prevalence of the bacterium Prevotella, which helps synthesize amino acids that help in muscle recovery.
â€œWithin two months I was a new person,â€ Petersen says. â€œI had no more fatigue. I could ride my bike hard three days in a row, no problem.â€ She started racing four months after her fecal transplant, and was winning races at the pro level soon after that. â€œEverything changed,â€ Petersen says.
â€œThe more a person trains, the more likely they are to have Prevotella,â€ says Petersen. â€œIn my sampling, only half of cyclists have Prevotella, but top racers always have it... itâ€™s not even in 10% of non-athletes.