I have a knee issue that I thought was imminent knee failure, but I bought these and 7 more pairs, and they are life savers. No pain. I work out every night, save Friday, 2.5-3 hours, and I wear them in the gym on th tread mill stairs. And now that I'm using my toes to spring off, the strength in my calves is amazing, hard as a rock
also i have the big toe on my right foot that crosses over the next toe, i put in a spacer, and now, because of the wide tow box, that toe is slowly training itself...