This Ab-Strengthening Plank Workout Is 100% Hard but 100% Good — Here's How to Do It

The Four-Minute Ab Workout

This ab workout should be completed with no rest in between each exercise. If you need to rest, try to take no more than 30 seconds in between each exercise.

Repeat three rounds of the following exercises:

• Elbow plank: 30 seconds
• High plank: 30 seconds

Repeat one round of the following exercises:

• Side elbow plank (left): 30 seconds
• Side elbow plank (right): 30 seconds