No Equipment
Core / Cardio
5 rounds for time. Go back to back from Double Under to Sit Up.
Jump Rope / 50 / 40 / 30 / 20 / 10
Sit Up / 50 / 40 / 30 / 20/ 10
Notes:
This is a classic CrossFit test of endurance and core strength. You can either do double under if your skills are there or single unders.