Taking a weekly 6 mg dose of the drug sirolimus doesn't help older adults get extra benefits from exercise — and might even cancel out some of the gains they'd normally see.

Older adults who take a weekly 6 mg dose of sirolimus while exercising might see slightly less improvement in hand strength and walking ability compared to those taking a fake pill — suggesting the drug could be limiting some of the usual benefits of exercise.

Taking a drug called sirolimus once a week might help older adults get stronger when combined with weight training, by giving muscles a break to clean out damaged parts between workouts — but we’re not sure yet if this actually works in people.

Older adults taking a weekly 6 mg dose of sirolimus while exercising for 13 weeks may have more side effects overall than those taking a fake pill, including a serious lung infection like pneumonia, even though about the same number of people had side effects in both groups.

In older adults who don't move much, taking a weekly rapamycin pill might slightly weaken the benefits of a 13-week home exercise program on leg strength and mobility, according to some detailed number crunching—even though the main results weren't clear-cut.

Taking 6 mg of sirolimus once a week might help reduce signs of aging and inflammation in older people, but we’re not sure yet and need bigger studies to confirm it.