Article in the NY Times: http://well.blogs.nytimes.com/2012/0...tervals&st=cse.

I have frequently done versions of this - essentially versions of Chris Carmichael's Fat Burner work-out - when short on time. This morning, for instance, I only had about 25 minutes for my Feb TE Challenge effort, so after a short warm-up I did 90 seconds on at max, 1 minute off. I was drenched.