Why is even a slow, short jog much more taxing than a long walk?

Question

I’m trying to do Couch to 5K at the moment to improve my personal fitness.

I can do long walks of an hour or more (10k+ in one go) with relative ease.

Yet a one minute run (which is Week 1 Workout 1 in C25K!) at an INCREDIBLY slow jogging pace is pushing my heart rate nearly to dangerous levels and I am finding it immensely challenging.

So what is it about a light jog that makes it so much more difficult than walking?

In: 38

Answer 1

When you walk one foot is generally always in contact with the ground and supporting your weight.

When you jog or run both feet are off the ground at some points, so you are pushing your entire body weight into the air temporarily. This takes a lot of energy you don’t expend when walking.