Question about leg articulation

[Greg H.]

From what I can tell, there are a few basic leg/foot articulation types. What I'm really curious about is the difference in two of them:

 

1. The human bipedal one (basically straight leg, 90-degree angle at ankle to foot).

2. The general "chicken" shape (theropod, avian)

 

The question I am trying to get a feel for is which leg shape is stronger at higher weights, and why. I don't know enough about engineering to be able to calculate the stresses on the bones with the varying bone angles.

 

So here's the proposed question:

 

Let us assume we have to identical cubes of lead A and B, each with a mass of 250 kilograms.

 

Cube A is supported by two standard human legs, while Cube B is supported by a theropod leg arrangement.

 

The question

Which set of legs would require less structural mass to balance the mass at a standstill, and support it with a normal range of motion for the given leg type?