I wear a heart monitor during my "formal" exercise (meaning: when I am dressed in exercise clothes working out to specific exercises). When I post on my exercise page that I did High Intensity, for me that means I got my heart rate up and kept it up in the high end of my target zone. High Intensity is different from High Impact. I do a mixture of high impact and low impact -- depending on what the exercise is and how my joints are holding up! :)
For my personality, I have found myself to be far more consistent with exercise when I exercise in the mornings at home using a large variety of exercise DVDs, which I have purchased over the years. I don't have to get all dolled up to go out, I wear mis-matched fitness togs, and have bed head!
Several years ago I joined (on-line) "The President's Challenge" and have earned the Bronze, Silver, and Gold Awards. I am currently working towards the Platinum Award. (I have 315,000+ points towards the 100,000 points required.)