When you use your heel on a horse, you have to slightly curl your leg up so it's not stretched down.. that's probably why you're losing your stirrup. Try to use just your leg.. if he isn't responding then maybe think about a crop. You don't want to compromise your position in any discipline.. because then you start losing stirrups and losing balance and whatnot.
Which part of you hurts when you are focusing on keeping your heels down? Do you push them down? What helps me is let that weight down is to think more about stretching my leg than pushing my heel/foot.
If it's your knee, then it could be stirrup length if it's not you pushing your heel/foot down.
Now, if your foot is sliding in.. that usually happens to me when I curl up for a bit, the stirrup naturally travels back and then I realize, put my weight back down (this all happens in about .5 seconds) and thus the stirrup has crept too far back. Then you try to adjust it and it keeps going further back till it's at your heel.
It could also be stirrup width. If the stirrup is too wide for your foot, then it's more prone to sliding back. It can't be too narrow else your foot wouldn't be able to go deeper into the stirrup.
I think, though, if you focus on putting that weight down into your seat the down your legs by stretching (instead of pushing) your leg, it may solve many if not all of those issues.
Breathe :) We'll help you figure it out
"Strength is the ability to use a muscle without tension"
Last edited by Skyseternalangel; 01-19-2012 at 12:23 AM.