text: When you begin to exercise, the body's response is to lay down new bone in the front of the shin area.  If you begin slowly, that new bone has time to develop, and harden.  If you push beyond that slow process, the new bone begins to shatter slowly, and microscopically.  The best method to avoid this is to begin your process slowly, so that the bone continues to form, yet not be stressed.  Shin splints are the leading cause of having to back off training of young race horses.  Trainers now know that when shin splints begin (It's called shin bucking) the trick is not to lay the horse up, but to back down on the speed and the amount of work.  If the horse is laid up, the new bone is absorbed.  So the cause of shin splints in horses, as well as humans is too much work, too hard, too fast....