This study was done to determine forces of hoof impact and the differences between a shod and unshod hoof in dampening the effects of these forces. Pressure in the digital cushion was also measured and hoof expansion studied to how it effects the shock absorption of the hoof. This study only used horses trotted in hand (no riders) and trotting on asphalt. The same horses were used with shoes and then with the shoes removed. The shod hoof had a greater acceleration force when hitting the ground (44 ms2) than a barefooted horse (23ms2) and also had a higher frequency of vibrations transmitted to the first phalanx (185 Htz) than the barefooted horses (155htz).

The pressure in the hoof was also measured and how it related to hoof expansion. In the barefooted horses, the pressure relief began sooner at about 30 msec after the hoof hit the ground, but in the shod hoof, the pressure release took longer about 50 msec.

The study concludes that the rapid hoof expansion in barefooted hooves allows for this more rapid release of pressure than in a shod hoof where the expansion is limited. The pressure relief also lasted longer in the barefooted horses than in the shod hoof.

Although the total power of the hoof impacts were about the same in barefooted and in shod horses, the barefooted horse was better able to reduce the effects of the impact and absorb more of the forces than a shod foot.