Define Power Walk Meaning

to walk fastly away from whom ever.

When people walk down the sidewalk trying to get home before they shit their pants.

What overweight people consider exercise, usually because they're too lazy to do proper exercise like jogging or swimming

An excellent cardiovascular exercise. Many people probably think that it's not so effective because it's not running and 'just walking', when really it can actually be just as good for weight loss as jogging.
Also, power walking is not simply walking at a faster pace. That's brisk walking. Power walking is walking at a fast pace (probably often even faster than brisk walking) with an arm swing.

In a relationship, one's ability and willingness to leave the other, or "walk away" from it. The less clingy person can be said to have the walking power.