Pains
I used to get leg pains
Cramp is caused by a build up of lactic acid. To prevent it, eats lots of green vegtables and warm up before playing.
You might need to build up more muscle
6 months of solid woodland in the winter will do the trick, thighs like bricks
Wear knee supports under knee pads. I tore carterlidge because I didn't, now I need surgery to correct it. York body builder ones get my seal of approval, you can get them from Argos from like £25 each.
Good luck bro