I am a distance runner, and I ran 25mg/ed winny alone for 5 weeks. I definitely got faster, and I wasn't as tired on my longer runs. I guess that's doe to the extra red blood cells. After I came off, I was basically back to the fitness level I was at ehen I started the cycle. My knees and shoulders definiely got stiff and achy, though. If you take Triflex, that shoudl help. I personally don't think you will need more than 30mg/day. I bumped to 50mg/day my last 3-4 days and the only difference was more joint pain and a little acne. I lost a few hars too (but I have plenty to spare).