I dove 3-meter springboard and 10-meter platform for years in high school and while at UM. Actually got hurt worse on the 3-meter but that's another story. Off the 10-meter platform you hit the water at around 28 mph. May not sound that bad but if you don't hit somewhat vertical you'll feel it. Can't ever say I had any issues where knees or ankles were hurt or seriously affected. Biggest issue tended to be the back. Tore a muscle once and spent 3 of the most painful days of my life flat on my back on a hard couch. But the most painful shot, including hitting pretty flat a few times, is when you go in feet first leaning slightly forward and wind up with your nuts for a bow tie. Now that is painful!