at a canter

I ride a Percheron cross, very smooth guy for being so huge but-i notice at a canter I have trouble keeping my left foot in the stirrup. My right stays planted with heel down and the left is wobbling about-i checked stirrup lenghth already- Why am I pulling only one leg up and not both? Any idea would help-i don't have anyone to take pics He has a huge rolling canter that is so comfortable, and it is only at a canter never a trot. I am concentrating on correct posture but am obviously doing something wrong here. Thanks for any input

I know you said that you've checked your stirrup length, but many people have on leg shorter than the other--I do. So your stirrups don't always have to be the same length.

I would just suggest working on making sure you are holding your horse with your legs and thighs and not just relying on your feet in your stirrups. I remember I had this same problem when I would ride a cantering horse and one of my legs would come up. I don't remember what the problem was, but I don't do it anymore. I think you could just try strengthening your legs.

Make sure you keep your heels down! I know it sounds obvious but sometimes this is the answer to problems with feet slipping out of stirrups. Alternatively, you could canter him without stirrups and see what happens.

Or perhaps you aren't sitting straight? Can you have someone stand behind you and let you know?

There is rarely anyone there but me-strange since the weather is so nice! I usually ride 4 days a week. My instructor moved 35 miles away and we all know gas prices so I am pretty much on my own now. I will measure the leathers and my legs and will also try the no stirrup thing. Very hard to keep legs down and back as he is so round. Thanks alot!!!

Sit slightly to the side of whichever leg slips up, to anchor your weight back down. Work the muscles in that leg more, and make sure your EVENLY pushing through your hips, and legs down to your heels, practise on the ground and take note of which leg is easier and which leg stretches furthr, may give you some clue about what your looking to actually fix

Its funny that I read this this morning after having 3 students in a row yesterday who all had a similar problem. Every time the source of the problem was their heels. If you don't anchor your heel your leg is more likely to slip back, heels up which will make it so much easier to drop your stirrup. It also often sends your upper body forward a little which doesnt help.

I wouldnt recommend leaning to that side to compensate for that. If you are going to lean then you will end up off centre therefore off balance and this doesnt help you at all. Work on keeping your heels down. A good way to do this is by 2 point seat in walk and trot. Your hips, knees and ankles should be like springs driving the pressure down the back of your leg to your heels. Be careful not to overdo it and push them down too far though :)

Having said all that, some people do have different length legs so I would check that. It might be good to get some pics or videos when you are riding and then it might be easier to tell.

Thank you for the tips, it was so mcuh easier on the Paint I leased prior to sonny as he was thin-sonny is so big around the barrell!!!
I will consentrate on heels down-my legs are ok it must be my posture and heels. Practice practice eh??/ thank you all again

You're not balanced in the tack. Instead of putting weight in your heal, you are gripping with your knee or leg.

Relax your leg and sink weight into both heals.

Does this happen with both leads? You could be compensating for balance.

Don't assume that because they are big, that their canter is hard to sit ;) it's usually the other way around