- Rest your top knee or ankle on a bench and lift your hips into a side plank.
- Start with the short lever (knee on the bench) before the long lever (ankle).
- Holds of 10 to 20 seconds are plenty at first.
- Expect some inner-thigh soreness early on, and build up slowly.
- Level
- Intermediate
- Trains
- Adductors, Obliques, Quadratus lumborum, Glute medius
- Kit
- Flat bench, Exercise mat
What the Copenhagen plank trains and why it is worth doing
The Copenhagen plank works your adductors, the muscles along your inner thigh, along with your obliques and the side of your trunk. The adductors rarely get direct training, yet they do a lot of work in running, changing direction, kicking and squatting.
Research in football has linked regular Copenhagen adductor training with fewer groin problems, which is why it has become a staple in team sports. It is also useful for runners, HYROX athletes and anyone who has had a groin strain and wants to rebuild strength, with guidance from a physio if the injury is recent.
How to do a Copenhagen plank
- Place a flat bench beside you and lie on your side on the floor, with your elbow directly under your shoulder.
- Rest the inside of your top knee on the bench (the short lever), with your lower leg resting along it. Your bottom leg stays underneath.
- Brace your trunk, then press down through your top leg and forearm to lift your hips until your body forms a straight line.
- Let your bottom leg hang, or bring it up to meet the underside of the bench.
- Hold while breathing steadily, keeping your hips high and your chest facing forwards.
- Lower with control and swap sides.
Common mistakes
- Starting with the long lever. Putting your ankle on the bench on day one puts a lot of force through the groin. Earn it with the short lever first.
- Hips sagging. As soon as your hips drop, the adductors stop doing the work. End the set there.
- Rotating the trunk. Keep your chest facing forwards rather than rolling towards the floor.
- Doing too much too soon. The adductors often get very sore after the first few sessions. Start with a small dose.
- Holding your breath. Breathe steadily throughout.
Easier and harder versions
To make it easier, keep your bottom foot lightly on the floor for support, shorten the hold, or start with a standard side plank and some side-lying adductor lifts. A partner can also hold your top leg instead of using a bench.
To make it harder:
- Move to the long lever, with your top ankle on the bench and your leg straight.
- Raise and lower your bottom leg to touch the bench for reps.
- Do dynamic reps, lowering your hips towards the floor and lifting back up.
- Increase the hold time gradually.
How to programme the Copenhagen plank
Start with 2 to 3 sets of 10 to 20 second holds on each side using the short lever, once or twice a week. Over several weeks, add time or progress to the long lever. For team-sport athletes and runners, a small dose done consistently all year is more useful than occasional big bursts.
It fits well at the end of a lower-body session or alongside other injury-prevention work such as the Nordic hamstring curl. The guide to strength training for runners shows how to fit work like this around your mileage.
If you are managing groin or hip pain, the on-site physiotherapy at Lycan Strength starts with a full assessment, and gym members get 20% off treatment.
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Questions
What is the Copenhagen plank good for?
It strengthens your adductors (inner thighs) and obliques. It is widely used in football and running to help make the groin more resilient.
Should the Copenhagen plank hurt?
You should feel your inner thigh working hard, and some soreness the next day is common at first. Sharp pain in the groin is a sign to stop and get it checked.
General guidance for healthy adults. If you have a medical condition, injury or are pregnant, check with a health professional before changing your training or diet.
