Canter Transition

Question
Hi, over the last few months my horse and i have changed riding instructors which has benefited both of us, the last couple of rides i have had a lot of amount of resistance going into canter through trot on the right rein which is he weaker side. when i ask for canter he will hollow out and has started drawing back/feels like canter on spot and it is quite hard to go with him, i have tried giving him the reins and just kicking him forward and also keeping the contact and kicking but still resists. we had a lesson the other night where he did it again and it just felt like he was getting higher and higher. the work now compared to 5 months ago is a bit harder, he is working the right muscles now (recently just had a massage) so i can understand this work is hard on him cos we havent been working correctly before that and we are both learning heaps.he is not a forward TB and is 15 years old, everytime i ride i pretty much need to tune him up to listen to my leg. i hope you can help. i just dont like the feeling of him getting higher in canter & hollowing out and ignoring what im asking him to do. thankyou

Answer
Dear Kara,
You begin your letter by saying that you have changed instructors in the last few months which has been of benefit you both you and your horse but then you go on to relate how you have been experiencing all of this right rein resistance. What you don't say is what this new coach has to say about the situation.I would ask- after all you ARE paying for this person's professional input.
It is pretty common for horses to have a rein preference- much like people are right or left handed. At fifteen- if he is finding this work difficult it's because he's been escaping it for many years and probably lacks flexibility, balance and muscle strength.
While always being cognizant that he IS 15 and your results will be somewhat fettered by this fact, I would add some strengthening work to your regime by working him in side reins at walk trot and canter at least 20 minutes a day with one day on and one day off. Make sure that he is used to side reins before you begin to take up flexion and contact with them or he could flip.
When you are mounted practice some leg yield and shoulder in, again to increase his suppleness. Steady contact with your outside support rein and light half halts through seat, leg and inside rein to encourage correct bend and flexion.
In canter, try spiraling in and out (think leg yield in canter on the circle). This will help to keep him focused on lateral movement.
I hope his is of some help.
S. Evans