Some Physics of Jumping

In “Jumping From a Height,” someone in the physics department at MIT wrote a good analysis of jumping and landing for a Physics 8.01X class for fall term 2002. (Thanks!) One screen capture shows the situation; another shows the force required to stop you when you fall.

As you can see, the force required to stop you is a multiple of your weight: it’s your weight (mg) times one more than the ratio of the height you jump to the distance through which you stop yourself — or, roughly, it’s your weight times (1 + (heigh fallen divided by how much you bend your knees)).

So, for a given height, the more you cushion the fall and absorb the blow, they less force it takes to stop yourself and catch your fall.