Working w/ splint injury?

Last week, my horse popped a high splint and has been on stall rest since. The vet checked him and said he will need one to two more weeks of stall rest and another 3 weeks in a separate field from his herd, for a total of 6 weeks off of work.

My problem is that he is a very forward horse who likes to work and is used to working. When he is not used for a while, he gets very spicy and just wants to go fast. Not only that but I have only had him for two months so we are still working on building trust and respect with each other. I’d like to keep the excitement down once he is back in work because I do ride him with beginner but also to prevent reinjury. Currently, he leaves his stall and go in small field for 30 minutes a day so he can move around a bit more to prevent stocking up but I am looking for something more to do with him.

I understand I am unable to ride him or longe him but is there any other way I can work with him to build trust while also keeping his mind working? Or any tricks I could teach him without risk of furthering the injury? I already groom him everyday but is there something more engaging for him?

My horse just finished recovering from a splint. Vet recommended 6 weeks of stall rest, and we made it about 4 weeks before he started to go stir crazy. His daily hand walks around the barn weren’t helping. Luckily my barn backs up to a trail system, so I started hand walking him on the trails. He became much calmer with the mental stimulation. So if you have trails accessible I recomend that. About week 5 I started tack walking him on the trails. We are just now getting back into work slowly, and so far it’s all been going well.