All rights reserved.
Backing in Hand
One of the easiest ways you can stretch your horse’s hind end
is by backing him in hand, preferably without tack on.  By
asking your horse to back up he is stretching his back muscles
as well as his hip, rump and hind quarters.  

Start by asking your horse to back just a few steps and then
let him walk forward.  Increase the distance the horse is
backing as he becomes more comfortable backing up.  The
horse needs to keep his head and neck in a neutral position so
he does not hollow his back by raising his head up.  If your
horse is raising his head, simply ask him to walk forward until
he relaxes his head and neck, and then ask him to back again.
 
You can graduate to backing your horse up slight inclines to
help your horse build muscle in his hind end while staying
stretched and loose.  Increase the slope of the hill as your
horse becomes supple and builds muscle.