Did you know that there is no joint connecting the front leg of the horse to the body? The front leg literally hangs from the withers, producing a limb that acts as pendulum when in motion. The scapula is attached to the withers by the trapezius muscle.
The muscles of the front limb must create the lift and suspension of forward motion. Then they must straighten the limb and lower it to the ground. This cycle of movement is repeated by the muscles of the trapezius, rhomboid,brachiocephalicus, latissimus dorsi, and pectorals for every step the horse takes.
You can see why massage is necessary to free up tight muscle tissue, enhance blood circulation, and improve muscle tone. For horses involved in competition, equine massage therapy can boost performance by improving range of movement, because you are improving muscle quality and circulation.