When your seat lands back into the tack while in the rising trot, you could be effecting your horses back.
To explain what I mean by my previous post, this answer is fine but it does NOT explain just what it effects and how.
So my question her is ...HOW ?
The purpose of the rising trot is to free your horses back, so when you land back into it for that breif moment, that could be effecting his/her movement.
Again...explain in what way.
Your heels are meant to take your bodies weight, to secure your seat and your lower body
How are you securing your seat and lower back by your heels?
I do not ride with my upper thigh, and my knees are always open *not gripping the saddle*
Agreed but open can mean so much to different people.
I ride with my heels taking my weight and my inner calf around my horses girth.
Some could take this explaination as meaning gripping
I am not saying that you post from the stirrups - but your heels should be taking your bodies weight - because they anchor you and aid you. When you grip with your knees or close your thighs, you effect your seat and you effect the flow that should be dipursing into your heels.
This may sound like you are contradicting yourself.
Leg position is imperative. Your legs must aid your seat, keeping the impulsion, and aiding in lifting the back and ribs. You do that through your lower leg, not upper.
Again you legs can be on the neck but you don't give any explaination than the leg position is important which I agree to but without saying why there is no substance to your words.
The post must be a soft, gentle movement. When you allow your horses movement to lift you out of your tack, there's not allot of work that you need to be doing.
I agree here.