I suffer from bad knees, at least i thought i did until these shoes. My problem i was running around in a pair of Adidas Climacool and they had nowhere near the support i need, so i did the research and decided on these, i have the crimson ones and they are excellent, put about 20 miles on them so far, been out 4 times with them and i have no more knee pain. i'm a big guy 220lbs 6,2, I'm losing weight fast and these are perfect for my weight and knees, they will only get better, even when I'm at my goal weight of 180lbs. Great shoe with amazing spring and support.