Chair seat, but only on one side??

[EchoInterrupted]

As per title - after reviewing some videos of my trot and canter in both directions, my right leg seems fine, but my left goes into a chair seat position. Just started riding again over the winter after 8 years off. I don't remember having any issues with this when I rode when I was younger. I've checked stirrup length, they seem even. I tried lengthening my stirrups a hole at someone's suggestions and even just watching my legs in walk, my right thigh stayed in even contact with the saddle while my left seemed to come off the saddle a lot more. Has anyone had this before? What did you do to fix it? Going to mention it to my instructor next week, but was just really shocked at how obvious it was once I started paying close attention to it!

 

[Rowreach]

Is this on one particular horse and one particular saddle, or any horse?

 

[stormox]

I would think possibly you aren't sitting evenly on both seatbones and/or are collapsing at the hip.
Can you get someone to watch you from behind and check your position?
Do you still feel uneven with no stirrups? Get this checked by an observer too.

 

[EchoInterrupted]

Is this on one particular horse and one particular saddle, or any horse?

Unfortunately I'm not sure - I have a part-loan at the moment and have only ridden him recently. I did ride one other horse back in October, and will try to take a look at some video. A lot of people on the dressage fb group where I shared the videos I mentioned on my current loan said the saddle did not fit me (I'm 5'10 so let's be real, that's no surprise), but I keep thinking surely it should "not fit" evenly? Unless it's unevenly flocked? I know the horse is stronger to the right though... not sure if that makes a difference?

 

[EchoInterrupted]

I would think possibly you aren't sitting evenly on both seatbones and/or are collapsing at the hip.
Can you get someone to watch you from behind and check your position?
Do you still feel uneven with no stirrups? Get this checked by an observer too.

Tried a bit of stirrupless on Wednesday and I felt way more balanced riding a trot circle in one direction than the other, but off the top of my head I can't remember which direction (I think it was more balanced to the right). He is a 18h bouncy monster, so it was a bit of a mess both ways tbh haha

 

[Rowreach]

Lots of factors at play here - as stormox says, you may not be sitting evenly on your pelvic triangle, but if the horse is unevenly muscled or the flocking is compressed on one side, that will put you in a wonky position before you start.

One thing I will say (pet hate of mine!) is that your stirrups looking like they are the "same" length is irrelevant it's not the starting point. Check the horse, check the saddle fits the horse and is evenly flocked, (it won't help if it doesn't fit you either), and then sit on the horse with no stirrups and check yourself (with someone there to comment/take photos) that you are sitting evenly over your seat bones and not collapsing at the hip.

A really good exercise is to sit on a table with your feet dangling, and feel your seat bones. Then try putting more/less weight into each, try tipping forward and backwards, and pushing each hip forward and backwards. It gives you a very good feel of how upright you should be when in the horse.

 

[thefarsideofthefield]

You may be sitting to the right and/or twisting to the left , so putting more weight in your right leg and/or collapsing through your left hip , which will cause your left leg/knee to come upwards/forwards to compensate . It can be difficult to feel if you are sitting ' straight ' with an equal amount of weight on each seat bone , so you may find it easier to think , instead , of keeping the weight in your left stirrup and pushing your left hip forward at every stride when you are sitting in walk/trot/canter or as you rise in the trot . Whenever you feel your left knee is coming up or you are turning onto the back of your leg , leg coming away , leg slipping forward etc - push your left hip forward to correct it ( and keep it forward ! ) .
An easy way to check for straightness is to wear a close fitting top and stick a piece of parcel tape ( or similar ) down the centre of your back ( spine ) from neck to tail bone and another piece horizontally around hip height , and get some one to film you riding from behind .

 

[CanteringCarrot]

I do this, sort of, with my right leg. My horse is a bit too wide for my body shape/hips. I have been really focusing on stretches out of the saddle and relaxing all muscles in the saddle. It has helped. Along with a change in saddle.

 

[EchoInterrupted]

Lots of factors at play here - as stormox says, you may not be sitting evenly on your pelvic triangle, but if the horse is unevenly muscled or the flocking is compressed on one side, that will put you in a wonky position before you start.

One thing I will say (pet hate of mine!) is that your stirrups looking like they are the "same" length is irrelevant it's not the starting point. Check the horse, check the saddle fits the horse and is evenly flocked, (it won't help if it doesn't fit you either), and then sit on the horse with no stirrups and check yourself (with someone there to comment/take photos) that you are sitting evenly over your seat bones and not collapsing at the hip.

A really good exercise is to sit on a table with your feet dangling, and feel your seat bones. Then try putting more/less weight into each, try tipping forward and backwards, and pushing each hip forward and backwards. It gives you a very good feel of how upright you should be when in the horse.

Ooh these are great suggestions, thank you! The parcel tape suggestion from @thefarsideofthefield is also great, thank you!

 

[ycbm]

All the checks suggested so far are sensible, but if you try them and still can't find an answer, you might consider whether the horse is just too wide for you. I sit with my weight to the right on any horse that is too wide for my hips.
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