but my mom won't let me work my barrel horse when she isn't around. I can ride bareback at a walk and trot, and I can lunge him, but I am not allowed to use barrels as he starts to act crazy when he sees them.
Is your horse FINISHED on the barrels? Or still in training?
If you horse is indeed a finished barrel horse, you often don't need to do barrel work in-between your runs. You just simply need to keep them conditioned.
Are there any exercises I could use to build muscle without breaking a trot or using barrels? I already ride him up hills bareback, but I'm not sure what else I can do. He really needs for hindquarter muscle, and I would love to try any exercises that improve balance. I stretch him a lot, but unfortunately, stretching cannot build muscle or improve balance too much. Any ideas? I can use a single barrel in the arena, but as soon as he sees three barrels, my mom says it becomes unsafe and she can't imagine me on him without her watching (I've never fallen off of him, but she says there's a first time for everything.) Any help is awesome! Thanks!
Have you checked out the sticky on this forum? Barrel Racing Exercises and Drills.
Lots of great info in there.
You don't need ANY barrels in the arena to work on things that can help your barrel racing.
You can do a reining pattern on him in the arena. (walking or trotting it, if you are not allowed to gallop)
You can work on "perfect circles". Basically, ask your horse to make a barrel turn with an imaginary barrel and expect your horse to have perfect bend in the body, nose turned in, and keeping their hindquarters under them. You can do this at all 3 gaits (walk, trot, canter).
Riding up hills is a great way to strengthen the hindquarters. Backing also helps build hindquarter muscle.
You can do rollbacks on the arena fence.
You can do spiral exercises, keeping his body in that "perfect circle" frame.
You can do serpentines.
You can do the barrel pattern with imaginary barrels.
Lots of things you can do!! You don't need barrels to keep your horse in barrel shape.