Here is a core circuit routine guaranteed to get your abs pumping!

PERFORM PER ROUND:

• 20 sec  – Crunches
• 20 sec – Leg Lifts
• 20 sec  – Russian twists
• 20 sec – Elbow Plank

Rest 45 sec -1 minute between rounds.

NUMBER OF ROUNDS:

• Beginner – 5
• Intermediate – 6
• Advanced – 7

Your Gymboss Classic Interval Timer makes a perfect HIIT workout timer.