Here are the core principles for HIIT:
- Warm up for 3 minutes
- Exercise as hard and fast as you can for 30 seconds. (You should be gasping for breath and feel like you couldn’t possibly go on another second.)
- Recover for 90 seconds, still moving, but at slower pace
- Repeat the high-intensity exercise and recovery 7 more times. (When you’re getting fitter, keep adding repetition until you’re doing eight during 20 minutes session)
- Cool down for a few minutes afterward by cutting down your intensity by 50-80 percent