Ive tried the yogurts Activia and another brand in pill form. I didn't notice a difference in digestion but perhaps you need to take them for a long time. My son took them for a long time (years). They were an expensive brand which his doctor recommended. They didn't help or hurt him. The doctor eventually said to stop, because she didn't see it helping. Do some research. I'm not sure how they would work for athletic uses. Ya never know.