This is a cardio workout based on intervals and a super set finish. Ride a bike 15 min x 3 sets. Every third minute you go as fast as you can for one whole minute and then back to normal speed. After the 15 minutes you take a rest for 30 seconds and the you start the next set. In total you do 3 bike sets. You finish the workout with a super set for you abs. Do the reps in one exercise and then directly start the second exercise befor you rest.