I do HIIT on the elliptical once in a while. I start with a five minute warm up. Then I'll jump right into max elevation and resistance for one minute - going as hard as I can - then drop it down to a very low setting for two minutes, then again max for one minute. I'll repeat for 20 minutes. It's a hell of a workout, as long as you go 100% for the one minute intervals.
5/19/15 at 9:25pm