Hi! If you have gotten the all clear from the vet , I would start off with 4 loop cerpintines then carry on to do some lateral work like leg yielding, turns on the forehand and Mabey some shoulder in /shoulder out?
Has he been checked by a vet ? Being rigid isn’t normal and could be related to pain, saddle fit, teeth or lameness issues.
Hey! I would do lots and lots of leg yelding, in walk, trot and canter! In walk and trot I would do it from one wall to the other, opening the inside rein and making him really bend! Always moving foward and never pulling back!
Hope it helps
I’d suggest a lot of stretching on a loose rein. I work with a mare whose back is a bit rigid, so sometimes our sessions are 85% nose to the ground-making sure however she isn’t leaning and pulling but still constantly keeping forward and light. I feel it relaxes her and complements the days we do jumping training. Hope that helps!
I would work on the flat in lots of circles. Find training aids (bit, draw reins) that can help the horse understand what you are looking for. Work on lots of bending each way to supple