Use your back

“Use your back like an accordion” Nuno Oliveira said.
He used the lower pelvic area to bring the haunches down, the midriff to lift the front end up to the hand and the shoulders to overload the hocks or release the hocks, depending upon which way he used his back.

So he used it in three parts and then he used it laterally to overload one side or the other to pivot the horse. He used his back diagonally to oppose a leg with an inside shoulder – the outside leg to the inside shoulder. Basically, he used his back like a clutch”.