First, lets define a lead: When the horse is loping in the right lead, the footfall pattern is left hind (beat one), right hind and left fore almost simultaneously (beat two), right fore (beat three). The right legs will be reaching the farthest forward and the horse is loping in the right lead.
To ask for a lead change, it is important to understand that the horse might pick up two leads, one with their front legs and one with their hind, if you ask incorrectly. This is called "Crossfire". If you ask the by moving their hip, they should always pick up the full and correct lead. So in order to ask for the correct lead, you need to get the horse to bend his body. So for example, to ask for the right lead, you:
- tilt the horses head to the inside (right)
-keep your inside leg on the cinch to have them lift that front shoulder
-apply pressure with outside leg behind the cinch to ask them to move that hip to the inside.
To ask for the lead change from right to left:
- you are currently applying inside inside (right) leg pressure at the shoulder
- tilt head to the left
- apply left leg pressure at the girth to ask to bend
- apply outside (right) leg pressure behind the cinch to ask them to shift their hip
When first asking for lead changes, bring the horse down to a nice controlled trot and ask for the change from there, then you can move up to flying lead changes.
Training a horse for lead changes is different:
Start with asking for a half pass as seen below
Half-pass to lope on correct lead:Walk your horse in a large circle on the right rein.
Make sure your right leg is not in contact with your horse.
With your weight to the left (it helps to really exaggerate this at first), apply right rein pressure in a “give-and-take” in the direction of your left shoulder – a rein of opposition.
I find I need quite a short rein to do this so my hand doesn't get too high.
Apply left leg pressure and steady direct left rein pressure until your horse steps to the inside of the circle with forward sideways steps.
Your right rein will be holding your horse on the circle and your left leg will be moving his hind quarters into the circle.
Ask for only a step or two at the beginning, using your voice or bumping softly with your inside leg for forward motion. Release all aids and repeat, then repeat to the left.
Half-pass to the inside several times, releasing after your horse performs the maneuver and walking a few steps. When you want to lope from a half-pass, keep your weight on the outside seat bone, release the rein pressure and “kiss”. Repeat a few times until your horse understands. Reverse and half-pass to lope in the other direction. Don’t expect too much too soon if your horse is learning. I accept any attempt to lope, then do it again.