Think a regular plank is challenging? Watch this video with fitness expert Lauren Williams to learn how to do a moving forearm plank. Because you’ll be transitioning through a few different positions, you’ll seriously strengthen your core muscles.

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Don’t have time to watch? Here’s the transcript:

This move is a moving forearm plank that forces you to activate your core as you move to different positions. You’re going to come onto your elbows and find a nice, solid core. I like to widen my feet so I’m super stable. From here, you’re going to reach one hand forward, and then alternate. Notice that my hips are not moving. That is your goal, to keep your hips nice and still, and parallel to the ground.