So, if I've got this right, applying ground force faster (which requires greater strength) leads to an increased stride length. Did I get it?

If I did, then the implication is:

The greater stride length would naturally allow the runner to get his striking foot under his center of mass?

And, looking at the posture of the 2nd runner, would you consider that his longer time on the ground might be related to what seems like his whole body (waist, back and neck) compressing when his front foot lands?