Endurance - 3 min intervals Workout

Every 3 mins for 4 rounds:

From 0:00 min to 3:00 min: 30 m walking lunges + 50 double unders
From 3:00 min to 6:00 min: 10 burpees + 25 sit ups
From 6:00 min to 9:00 min: assault bike for calories

1 min rest between rounds.