What is a Copenhagen board?

If you have cardiovascular problems, musculoskeletal pain or injuries, or other health conditions or injuries that interfere with your ability to exercise safely, talk to your doctor before trying the Copenhagen plank to see if it’s right for you, says Fredericson.

Use caution if you have a history of shoulder injuries. “It can be too difficult to maintain the elevated side plank position,” says Matt Kasee, CSCS, a certified strength and conditioning specialist in Cincinnati. And those with a history of knee problems may find that supporting one leg on an elevated surface is too stressful on their knees, Kasee ​​adds.

To make a Copenhagen board:

• Lie on your side with your lower forearm and hand firmly placed on the floor, elbow directly under your shoulder, and both legs straight.
• Place the side of your top foot on a sturdy box or bench.
• Press the edge of your top foot onto the surface of the box or bench and lift your hips off the floor to form a straight line from head to toe.
• Lift the bottom foot off the ground so that it hovers a few inches below the top foot.
• Look forward while you hold this position.

“You can do this in repetitions by raising and lowering your hips or holding your hips up for a set amount of time,” says Kasee. Start with 30 seconds or 10 repetitions per side and gradually increase the duration or number of repetitions as you get stronger.

Don’t let your hips sag toward the floor during the Copenhagen plank. This compromises your alignment and reduces the effectiveness of the exercise. Kasee ​​says this is often due to the hip adductors and core not being strong enough for the position. “To fix it, slide more of your upper leg over the support,” he suggests.

Another key mistake is moving your torso forward, which Kasee ​​says is often due to insufficient core and shoulder strength. To remedy this, he advises switching to a traditional side plank so you can build shoulder and core strength and endurance. Once you have mastered the correct technique, you can try the Copenhagen plank again.