HI all,

I am leaving for a week to a seminar, and I thought I'd leave you all with a nice puzzle to debate upon. I actually don't really have a specific answer, and would like to hear the opinion of others.

Here goes:

A long distance runner thought of a brilliant idea. He will add 2cm to the thickness of his soles increasing his pace length by approx. 1cm. Over thousands of steps made in a long distance run, this 1cm increase starts to be significant.
Is this idea really as brilliant as it sounds?

Let me stress that there are arguments for both sides, and I have a few of my own. Let's hear yours...

Nir

I wonder if such a runner would benefit from platform running shoes with the platform 50cm high?

Have you ever tried to run on stilts?

It would add a centimeter of torque if he twisted his ankle.

The added weight would be a factor. Would he need to exert extra energy to get the grounded leg straight?

Imagine the new show is as heavy as the normal shoe.


Nir

OK, so let's make them a meter thick with weight not a factor. It seems like a single stride would be very long, but it would take quite a push to shift your weight onto the leading foot. Stilt walkers seem to take small steps. Is it because of this? This would have to be a factor on our smaller shoes.

But, then again, longer legs are clearly an advantage. So, why not taller feet?

This might help while walking as someone may walk slowly and place their heel at an angle, thus giving a slight benefit. However, a runner lands on the ball of his foot, and also seems to push from the center of his foot when propelling. So, I think there is little difference. Maybe even a negative due to weight.

Something about the extra knee motion seems important here.

As I said guys, keep those arguments coming. I DO NOT have a strict answer.

Nir

Isn't this really the difference between a sprinter and a runner? The sprinter runs on his toes to lengthen his stride, but at the expense of more energy in a shorter period of time. He couldn't run the marathon as a sprint.

So, I think the limit for this runner is not the length of the stride, but his ability to expend energy efficiently. I do not think the lengthened stride adds to efficiency.

0pus

I think the common wisdom is that someone with short legs is never going to win a race. But, legs longer than a certain optimum amount don't give you an extra advantage. As mentioned above, there are considerations as regards to weight and even angular momentum. And the difference between styles in sprinting and distance running means that the longer legs are more likely to be of a greater advantage in a sprint rather than a marathon. In a marathon, efficiency and stamina are much more important.

Bottom line? I don't think 2cm is enough of an increase to do much for a sprinter (besides ruining his stride), and it's of no use to a distance runner at all.