Andy McKenzie is an expert in bodyweight and core training. This week, he introduces the iron flag. This is an advanced exercise for core strength and a variation on the dragon flag. It requires shoulder strength and stability. Learn how to do a regular dragon flag before attempting this version.

You will use two kettlebells to add resistance, hence the name iron flag.

1. Lie down on the ground, face up.
2. Press the two kettlebells above your head.
3. Raise your feet as high as possible then slowly lower them, trying not to bend at the hips.

This is a difficult exercise, and the kettlebells may drop to the floor. To raise them overhead again:

1. Keep your core tight.
2. Squeeze your glutes.
3. Stay stable.
4. Drive your palms toward your hips.

This exercise is more difficult than it looks. Perform as many reps as you can, and don't give up!

Check out these related videos:

• A Core Training and Shoulder Rehab Exercise for Athletes
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