This table gives us the tensile strength, in Newtons per metre squared, and the average cross-sectional area in metres squared for four bones vulnerable to injury in this type of fall. By multiplying the tensile strength and the cross section we obtain the maximum force each bone is able to sustain without breaking. Because the fall would extert lateral force on the bones, rather than vertical, the actual forces required to break Bruce’s bones would be smaller.

From the table we see that a force of 18400 N would not break any of the four bones analyzed. Right, so he didn’t get cut in half. But what about head injuries from shear strain? (Shear strain is how the shape of an object changes as the result of forces).

Rapid deceleration of the head can lead to serious injury to the brain stem due to shear strain. This is measured by what’s known as the severity index I , which has been determined experimentally by the equation:

(Man, we love those equations!) Where v is the velocity at impact, t is the duration of impact, and g is the acceleration due to gravity. When the severity index for a collision is above 1000, the collision is fatal. When the value of the severity index is about 400, unconsciousness and mild concussion are the result. So let’s work it out.