how long should the sprint be for interval training

whiteberry17

how long should the sprint be for interval training? Im gonna go for 3.0 speed then switch for 7.0 speed for the sprint.
I usually go 1 minute on my sprint then 1 minute on slow and I alternate. Should I keep the sprint at 1 minute or 30 seconds. Which burns more calories?

55in13

I have no idea what 3 versus 7 is compared to other things besides your machine, but the slower pace is usually done longer than the intense pace. The intense pace should be nearly all out; if you could keep the pace for 50% longer than you do, then it may not be intense enough. The kind of HIIT that gets the crazy calorie burn numbers is very difficult to do.

This article recommends 30 seconds high and 1 minute low. Read what he means by high:
http://www.brinkzone.com/training-programs/hiit-training-are-you-really-doing-it/

loveplayer33

i would do 1 minute of slow ( 3 ) and than 30 seconds of faster ( 7 ) . when that gets easy bring it up to 4 and 8.

LERadicalDreamer

I'm doing one minute fast, and ninety seconds of a brisk walk. Working really well!