Many times beginner riders will have difficulty keeping their horse on the
rail, in lessons. The horse may drift inward or cut corners. I have
noticed a tendency in many beginners to want to pull a horse back to the
rail by using the outside rein. This doesn't work :) and I'll tell you
why:
Say you're going around the arena to the left;
When you get to a corner, you use your left rein and left leg to make
the turn. Keep contact with outside rein and outside leg, but these are
not "active." For more about why your legs should be "on" the horse,
even when you're not using them, see Point your
Toes In.
If your horse begins to drift off the rail, you may try to pull him
back on with your right rein (outside rein). What you've just done is
to counter-flex the horse; that is, you've bent him the wrong
way.
Now even though you're using your left (inside) leg to ask the horse to
move to the right, he's still not going to be able to do so. He's bent
the wrong way, and he can't circle into the rail.
Let's look at circling, briefly. When you circle, to move out on the
circle, you use inside rein & inside leg; to spiral in, you use
outside rein & outside leg.
When you're travelling along the rail, you're just making a very large,
rather squared circle. If you want to open that circle--move toward the
rail--you need to flex in the proper direction (to the inside), and use
inside leg.
So when you have flexed the horse in the wrong direction, you have not
made it easier for him to stay on the rail. In fact, all he *can* do,
flexed in that direction, is to "open" the circle or move "out" towards
his shoulder--but his shoulder is toward the inside of the arena! By
bending the horse in the wrong direction, you have actually made it
easier for him to drift off the rail.
Use you inside rein and inside leg, "open" the circle, and it will be
easier to stay on the rail.
Do be sure you don't lose contact on the other rein. If you don't have
contact on both reins, your horse can just pop his shoulder in and go
wherever he wants to anyway :) But the rein you're using should be
"active" while you maintain contact with the other.