A question was posted in a horse training help group that got me to digging around in my brain for the answer.
She was having trouble getting her horse to keep the lead she asked for. When her horse tried to stop or turn out of it, she would spur him through it until eventually the horse balked & acted the fool.
All training comes from the ground first. If you can't get it on the ground, you're not going to get it while riding.
Her horse does fine on the lunge. Picks up the correct lead & goes around like he should. So what's the problem while riding? Usually the problem is corners. A lot of times when you work in a square arena, you have square corners & the horse sees this as "the end of the line" so it either stops or turns a 180, sometimes leaving you in mid air if you're not prepared. We see the corner as oh, we need to cut this corner & go around making an oval. 2 different perspectives.
When you come to the corner, gently pull on the inside rein. This gives your horse the signal that he's suppose to keep going, and to bend around the corner. If your horse is the type to "roll back", you'll need to pick up that inside rein & turn him in a smaller circle, then push him through to the straight side. Once your horse figures out that it's suppose to bend around the oval, it should correct the problem of stopping or the 180.
Practice makes perfect as they say, just don't over do it. Once your horse gets the idea, practice it a few "good" times then quit. You may have to repeat the process when you get back on the next day, but it should go more smoothly until eventually you no longer have the problem.
This problem can happen in a more round arena, though it's not real likely. The same principal applies no matter what shape the arena is that you use.
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