The Copenhagen plank, also commonly referred simply as an “adductor side plank”, is a fantastic exercise to include into your fitness routine.
Popular with Strength Coaches and Physical Therapists alike, the movement can help improve lumbopelvic stability, core strength, and healthy hip function.
The benefits of healthier hips can address musculoskeletal problems in other areas of the body too, such as knee pain and back ache.
But the movement does need to be executed properly to ensure you gain the benefits and don’t cause injury to your back.
In this exercise guide, we’ve got tips on how to do the Copenhagen plank properly, the muscles worked, benefits and things to consider when doing the movement. We’ve also included ways to progress and regress the movement to help adapt it to your current fitness level.
What is a Copenhagen Plank?
A Copenhagen plank is a side plank variation that involves resting your top leg on a bench or raised surface. The bottom leg hangs underneath the bench. Lifting your hips off the ground until your back is straight, you simply hold this side plank position for the duration specified.
The exercise is isometric and involves a “squeezing” movement to keep your legs together.
You can make the exercise easier by resting the bottom leg on the floor, or positioning yourself closer to the bench.
To make things harder, you can also include a dynamic hip movement by lowering and raising your hip to the ground or using a suspension trainder instead of a bench.
Copenhagen Adduction Exercise
The Copenhagen plank is a practical adaptation of the “Copenhagen adduction exercise”, which involves a training partner holding the top leg (as opposed to resting it on a bench).
How to do Copenhagen Planks
To do the Copenhagen plank:
- Start by lying on your side, like you would for a regular side plank.
- Place your top leg onto a bench or raised surface. The closer your body is to the bench, the easier the movement becomes.
- Bracing your core and keeping your obliques and abdominals tight, lift your hips off the floor so your back is straight.
- Lift your lower leg off the floor so it hangs under the bench, unsupported.
- Squeeze your thighs to hold this position.
- Repeat on the other side.
Coach’s Tip – Ensure you use a bench or raised surface that is roughly the same height as your head when you hold the side plank. This will mean as you place your leg on the raised surface, and lift your hips, your back should naturally be nice and straight.
The Copenhagen plank primarily targets the adductor muscles of the hip. These muscles are responsible for moving your legs to the center of your body.
These adductor muscles include the: adductor longus, adductor brevis, adductor magnus, and gracillis.
As well as hip adduction, Copenhagen planks will also help develop overall core strength by engaging the abdominals and obliques.
Benefits of Copenhagen Planks
Countless studies have shown that the Copenhagen adductor plank is second-to-none when it comes to developing adductor strength.
Although this may not sound like the most exciting muscle group to strengthen, it is actually incredibly important for healthy functional movement.
The adductor muscles also help support better athletic performance, especially in sports or activities that involve running or kicking.
Similarly, the ability to protect your hips with stronger adduction, will help with weightlifting too… and this subsequently means you can lift or train more intensity during squats, deadlifts and other exercises, which will lead to increased strength in other muscles such as the quads, glutes and hamstrings.
Reduce Groin Injuries and Pain
Ultimately, the benefit of stronger adductors is the reduce risk of groin injuries and pain.
Groin injuries are particularly common in sports that involve kicking, running or even jumping… and weakness in adduction strength has recently been highlighted as a root cause in new research.
Better Kicking Power
Stronger adduction means you can move your leg with more power and precision. For athletes, this is a huge competitive advantage and means better kicking power.
The human body doesn’t cope with imbalances very well… in fact, imbalances are a recipe for disaster when it comes to injuries.
The reality is many people will naturally do movements and exercises that strengthen the hip abductors (the outside of the hips). Clam shells, for example, along with lots of “glute” exercises, will help strengthen these outer hip muscles… which is undoubtedly important.
However, having very strong abductors, but weak adductors, won’t create the overall stability around the hips that you need.
Ensuring you are actively training for adduction strength as well as abduction strength will provide more overall benefits.
An interesting study that Physio-Network highlights in this article showed that groin injuries increased by 17 times when adductor strength was less than 80% of abductor strength.
Activate Core Muscles
As well as developing hip strength, the Copenhagen plank is also a great way to activate the core muscles, especially the obliques.
Similar to a standard side plank, your obliques are required to help create stability as you hold the position.
Strengthening the obliques helps to better stabilize the torso and spine, helping to promote better posture, as well as rotational strength.
Lateral Power and Movements
Any sort of lateral movement will involve careful coordination between adductors and abductors to move meaningfully in a sideways direction.
This ability to strengthen the adductors helps to ensure your lateral movements aren’t solely reliant on your abductors.
This helps to improve exercises like lateral side squats too.
Copenhagen Plank Progression
In our opinion, the best way to progress this movement is to use a suspension trainer (like a TRX system) to rest your upper foot.
The suspension trainer isn’t stable like a bench, so it will wobble and move. This means your core and adductors have to work extra hard to maintain stability.
This is a surprisingly big jump from regular Copenhagen planks and a great target for those looking to really leverage the benefits of the exercise.
Ultimately, the scientific research around Copenhagen planks is very positive and suggests athletes can improve performance and avoid injuries by including the exercise into their fitness routines.
For non-athletes, the exercise can simply help to create better hip stability, which is associated with reduced risk of back, hip and knee injuries as well as better posture.
Try and hold the Copenhagen plank for as long as possible, repeated a few times a week. A 30 second hold would be really good and a 60 second hold would demonstrate very good adduction strength.
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Featured image and video demonstration credit – AchieveFitnessBoston