8 min Intense plank workout Dolphin spider plank Alternative side plank hold Mountain climber Plank twist (4 reps) Plank back back and forth Rest 30 Inchworm leg lift hold Knee touch crunch plank Bear plank walk taps Alternative plank leg reach Rest Side plank hip raise Side plank hold Side plank hip raise Side plank hold Mountain climber hold (4sec) Plank jack and hop