Intensity! What?

I realized in my last post there could be some concern on what is high intensity and moderate intensity.  The answer is a percentage of VO2 max.  Seeing as most people can't calculate that on a regular basis.  I like this quick and dirty way of determining exercise intensity on http://www.weightwatchers.com/util/art/index_art.aspx?tabnum=1&art_id=20971.

Level of Intensity RPE Physical Cues Light Easy Does not induce sweating unless it's a hot, humid day. There is no noticeable change in breathing patterns. Moderate Somewhat hard Will break a sweat after performing the activity for about 10 minutes. Breathing becomes deeper and more frequent. You can carry on a conversation but not sing. High Hard Will break a sweat after 3-5 minutes. Breathing is deep and rapid. You can only talk in short phrases.