<em>The other problem is the "brisk" qualifier. Walking "briskly" actually takes significant motivation, and involves either subjectivity or more monitoring tha

<em>The other problem is the "brisk" qualifier. Walking "briskly" actually takes significant motivation, and involves either subjectivity or more monitoring than people like to do while their walking.</em> I think you're overthinking things. If walking seems to easy, jog. If jogging is too easy, run. If say, running is too hard, run when you can, take breaks by walking. If walking is too easy, you start with standing and doing basic drills in movement. There's always a level you're at, and something you can use as a goal. Easiest to not fall to low in what you can do, which is more of a preventative thing, unfortunately for those at a lower level of physical fitness.