Should I support my leg with my knee or ankle on the bench?

Start with your knee on the bench for an easier variation that reduces leverage and allows you to build foundational strength. Progress to ankle support as you develop the strength to control the longer lever arm.

How do I make the Copenhagen plank easier when starting out?

Keep your bottom knee on the ground instead of extending the leg fully, which reduces the load while still targeting the adductors. You can also use a lower surface than a standard bench to decrease the range of motion required.

Why do I feel this more in my shoulders than my adductors?

You likely need to press your top leg more actively into the bench to engage the adductors properly. Ensure your supporting shoulder is stable and packed, and focus on creating tension through the elevated leg rather than just holding yourself up.

Copenhagen Plank

The Copenhagen plank is a side plank variation where your top leg is elevated on a bench, creating intense isometric tension in the adductors and obliques. It suits lifters looking to strengthen the groin and inner thigh muscles while building lateral core stability.

Muscle group: Core
Primary muscles: abs
Equipment: Bodyweight

How to do the Copenhagen Plank

Position yourself perpendicular to a bench with your forearm on the ground directly under your shoulder.
Place your top leg on the bench with the inner knee or ankle resting on the surface, depending on difficulty level.
Lift your hips off the ground and extend your bottom leg, keeping your body in a straight line from head to feet.
Squeeze your top leg into the bench while engaging your core and maintaining neutral spine alignment.
Hold the position for the prescribed duration, then switch sides.

Form tips

Press your top leg firmly into the bench throughout the hold to maximize adductor engagement and prevent sagging.
Keep your bottom shoulder packed down and away from your ear to maintain stable shoulder positioning.
Align your hips vertically by squeezing your glutes and bracing your abs rather than letting your top hip roll backward.

Common mistakes

Letting the hips sag toward the floor reduces tension on the target muscles and places excessive stress on the lower back.
Placing the bench too high before building adequate strength forces compensation through shoulder elevation and hip rotation.
Allowing the top hip to roll backward breaks the lateral line of tension and shifts work away from the adductors and obliques.

Sets and reps

Perform 3 to 4 sets of 15 to 30 second holds per side for strength, or 3 sets of 30 to 45 second holds for muscular endurance.

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Frequently asked questions

Should I support my leg with my knee or ankle on the bench?: Start with your knee on the bench for an easier variation that reduces leverage and allows you to build foundational strength. Progress to ankle support as you develop the strength to control the longer lever arm.
How do I make the Copenhagen plank easier when starting out?: Keep your bottom knee on the ground instead of extending the leg fully, which reduces the load while still targeting the adductors. You can also use a lower surface than a standard bench to decrease the range of motion required.
Why do I feel this more in my shoulders than my adductors?: You likely need to press your top leg more actively into the bench to engage the adductors properly. Ensure your supporting shoulder is stable and packed, and focus on creating tension through the elevated leg rather than just holding yourself up.

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