I recently started riding an ex race horse, he has been off the track 4 years now however was never re-schooled properly and the last girl who rode him had no confidence so he was labeled as a 'bad horse'. When I first started riding him in was in a harsh bit, martingale, and flash but I took it all off he goes perfectly in just a french link egg butt snaffle. I took him out a few times and he rode fine but a few weeks ago I was cantering along a path and he wouldn't stop and just kept going faster which ended up with me falling off and in hospital! Obviously my panicking just made me more tense and I pulled more on the reins making him go faster, at that time I had no idea of any of his history and all the information I was told was incorrect so I had no idea what I was doing was causing him to go faster. Tried one rein stop and was leaning right back but he took a hold and lent on the bit so nothing like that worked. He's never bolted in the school he just used to spin, buck, and rear. I've been told to put him in a harsher bit and martingale next time I take him out but I think these things make him more anxious so I'm not sure what to do when I take him out and if he bolts again, any suggestions(bits, stopping techniques, training)? I was thinking taking him to a big field and working on slowing him down from canter in somewhere other than the school but with more room than the path we were on. Sorry for long post!