Training tips please

[pistolpete]

I have been getting resistance from my horse as I try to up the challenges for him. Only straight lines but he has been going through extensive rehab from lameness and other issues. He is healthy now but finds working over his back a challenge. Best tips to help him achieve it without tension?

 

[PorkChop]

Try poles on the ground, either in hand or ridden - a curve, box, channel, you can then progress to them being raised at one end.

Also lots of walking up and down hills - good luck with the rehab