I found some old ankle weights in my closet and decided to try them out. The box said they were 10 pounds each but I think they were closer to 5 or 6. Anyways, I put them on and me and my friends were joking around with them. We raced my 8 year old brother and tried to do leglifts and pullups. I thought they were kind of dumb... until I took them off and felt GREAT. I felt like the fastest kid in the world. I felt like I had Henry-like quickness. The next day I planned to go out and just do some running and other warm-up stuff like kariokes, highknees and other kinds of stuff. I got bored of that quickly and ended up trying to chip a basketball across the yard or do triple scisors. When I took them off I again felt great. I felt like I could shoot harder, run faster, kcik a ball like it was a baloon, do moves quicker, and do it without using any effort at all. I decided to warm up for a game with them on. I know that baseball players use bats with weights on them to warm with so I thought that it would be okay. My coach called me a dork but I definitly noticed a huge difference during the game. I had thought that warming up with them on might tire me out too fast but I had more energy left at the end of the game than I ussually do. My teammates noticed and were all asking to use them after the game. I've been using them for a couple months now and I love them. I have become a very fast player and everyone else just seems to get a little "heavier" every week. Anyone else ever use ankle weights before? Any injuries they are know to cause? I'm only 17, but I have back problems sometimes. If they are safe to use I would recomend them to everyone.