The amount of energy required to fracture the shaft of the femur was shown to vary with the rate of application of the load. One member of each of 32 pairs of femora was fractured with a gradually applied bending load. The mean energy required to cause failure of the specimens was 20.50 ft-lb. Impact tests in which the same loading geometry was employed, were performed on the remaining member of each pair of specimens. The impact loading velocity was 32 ft/sec. The mean energy absorbed to the point of failure by the impact loaded specimens was 31.33 ft-lb.

Attention was drawn to the possible significance of these findings in the field of accident protection studies.