HIIT [ 25 sec ON / 15 sec OFF ] Switch exercise at each interval. Repeat the circuit 2 times without rest between each circuit. *During the 15 sec rest, you can either rest or, if you want to increase the intensity of this workout, you can hold some exercises (as shown in the video).

List of exercises:
- High to low plank (option: plank hold during rest period)
- T-plank (option: side plank hold on right side during rest period)
- Plank knee-to elbow & opposite R (option: side plank hold on left side during the rest period)
- Plank knee-to elbow & opposite L
- Roll back crunches (option: V-hold during the rest period)
- Opposite toe touches