Originally Posted by myhorseMia
i don't think she would really enjoy barrels, but I would only be doing the pattern like once a week
If your horse does not like doing the barrels, don't force her to.
If she's getting hot on the barrel pattern already (and you've only taken her to a couple gaming shows) then you are pushing her too hard too fast.
There's absolutely nothing wrong with teaching an older horse a new event. So long as the horse is sound for it, and the horse enjoys it too. But that doesn't mean you can rush through training and skip vital steps the horse needs to be successful.
Check out this thread for training tips. Barrel Racing Exercises and Drills.
It takes 6 months to 2 years to train a horse to run barrels. It will take you much close to that 2 year mark if you only work on the barrels once a week.