To do the Copenhagen plank correctly, lie on your side with your bottom elbow under your shoulder, place your top leg on an elevated bench, and lift your hips until your body forms a straight line with your bottom leg suspended in the air.
Press your elevated leg into the bench while keeping your core tight and maintaining that straight alignment from head to feet without letting your hips sag or your torso rotate.
Keep reading for a complete breakdown of proper form, common mistakes that sabotage your results, and a proven progression path from beginner to advanced variations.
What Makes the Copenhagen Plank Different
Most planks have you facing down, working your abs and front core muscles.
The Copenhagen plank flips this approach entirely—literally.
You're on your side with your top leg elevated on a bench or platform while your bottom leg hangs suspended in the air.
That unusual position isn't random.
Danish researchers developed this exercise while studying how to prevent groin pulls in athletes.
They needed something that specifically targeted the hip adductors—your inner thigh muscles—since traditional planks largely ignore them.
The result was an exercise that addresses a common weak point in most training programs.
Here's what sets it apart from standard plank variations:
Target Focus: While regular planks hammer your front core, this one works your lateral stability and adductor strength at the same time. Your inner thighs get direct work instead of just tagging along for the ride.
Functional Carryover: The position closely mirrors a runner's stride, particularly that high-knee positioning. This makes it especially valuable if you run, sprint, or play sports that involve quick directional changes.
Muscle Recruitment: You're recruiting muscles that rarely get isolated attention—the adductors that stabilize your hips during movement. These same muscles are often the culprits behind groin strains and injuries that sideline athletes.
Think of it as filling a gap in your training that you probably didn't know existed.
Where traditional core work builds front-to-back strength, the Copenhagen plank develops side-to-side stability and strengthens muscles that protect you during lateral movements.
Muscles Worked and Science-Backed Benefits
Your adductors do the heavy lifting here.
These are three specific muscles on your inner thigh: the adductor magnus, brevis, and longus.
The longus takes the most abuse during athletic movements, making it the most commonly injured of the trio.
When you hold a Copenhagen plank, these muscles work hard to keep your legs together and your body stable.
But you're not just working your inner thighs.
The exercise pulls in your abductors on the outer thigh, your obliques along your sides, and your transverse abdominis—that deep core muscle that acts like a natural weight belt.
Your inner and outer thigh muscles fire together to maintain lateral stability throughout the hold.
The Research That Matters
A 2019 study followed male football players who added adductor strengthening to their training programs.
The results showed a 41% reduction in groin problems—a significant drop that caught the attention of strength coaches and sports medicine professionals.
Even more impressive: research from 2016 tracked male soccer players who performed Copenhagen exercises twice weekly for eight weeks.
Their eccentric hip adduction strength jumped by 35.7%. That's the kind of measurable improvement that translates directly to performance and injury resilience.
Here's the kicker—there's a dose-response relationship at play.
More training volume over a 6-8 week period produces greater strength gains.
You're not guessing whether this works; you're following a proven protocol.
Real-World Benefits You'll Notice
Beyond raw strength numbers, you'll develop better core stability and balance.
Your proprioception improves—that's your body's awareness of where it is in space, which matters when you're moving quickly or adjusting position during activity.
The coordination gains carry over directly to running mechanics, especially high-knee positioning.
If you run or play sports involving sprinting, you're training movement patterns that show up when it counts.
This isn't abstract strength that looks good on paper but disappears during actual performance.
It's functional power that protects you and improves how you move.
Step-by-Step Setup and Proper Execution
You don't need much to get started—just a comfortable surface for your forearm and something elevated to support your leg.
A bench works perfectly, but a sturdy chair, box, or step does the job too.
Pick a height that lets you maintain proper form without straining.
Getting Into Position
Lie on your side next to the bench.
Place your bottom elbow directly under your shoulder, perpendicular to the bench—not angled forward or back.
Extend both legs away from your body and position yourself so your top leg can comfortably reach the bench when lifted.
The Execution Sequence
- Lift your hips off the floor while bringing your legs together
- Rest your top leg on the bench with your bottom leg hanging suspended in the air
- Push your body up until you form a straight line from head to feet
- Press your elevated leg actively into the bench—this engages your adductors
- Hold the position while breathing normally and evenly
That breathing detail matters more than you might think.
Holding your breath spikes your blood pressure and can leave you dizzy.
Instead, focus on steady, controlled breaths throughout the hold.
Your alignment needs constant attention.
Your shoulders, hips, and feet should stay in one straight line.
Keep a slight forward pelvic tilt to maintain a flat back position—this protects your lower spine and keeps the right muscles engaged.
Mental Cues That Lock In Form
Picture an imaginary wall running along your back.
Your heels, glutes, and the back of your head should all stay in contact with this wall throughout the exercise.
This visualization helps you catch alignment problems before they happen.
Feel the tension building in your inner thighs—that's your adductors working.
Your core should feel tight and engaged, not relaxed.
Keep your torso square and stable.
Any rotation or twisting means you're losing the position and compromising the exercise's effectiveness.
The key difference between doing this exercise and doing it correctly comes down to active engagement.
You're not just resting your leg on the bench and hoping for the best.
You're pressing into that surface, maintaining tension, and controlling every aspect of the position.
Critical Form Mistakes That Kill Your Results
Small technical flaws turn this effective exercise into a waste of time—or worse, a path to injury.
Here are the mistakes that sabotage your progress and how to fix them.
Sagging Hips
When your hips drop toward the floor, you create a banana shape instead of that straight line you're aiming for.
This dumps unnecessary stress onto your lower back and lets your adductors off the hook.
If your hips aren't elevated and aligned with your body, you're missing the entire point of the exercise.
Keep them up and locked in place throughout every second of the hold.
Torso Rotation
Your shoulders want to rotate forward—it's a natural compensation when your core gets tired.
Fight this tendency.
The moment your shoulder twists, your core engagement drops and you lose the stability benefit.
Imagine leaning your entire body against a wall behind you.
Your core, glutes, and back should all fire together to keep your torso square and stable.
Arm Positioning Errors
Your supporting elbow needs to sit directly under your shoulder.
Too far forward and you'll pitch off balance.
Too far back and you can't generate proper support.
This positioning affects everything else in the chain, so get it right from the start.
Letting Your Legs Go Passive
Simply draping your leg over the bench and calling it a day doesn't cut it.
You need to actively press your top leg into the surface throughout the entire hold—that's what engages your adductors.
Your bottom leg shouldn't just hang there like dead weight either. It should contribute to the position, working with your top leg to maintain stability.
Hip Flexion Problems
Flexing your hips too much shortens your adductors slightly and shifts how the load hits them.
The change seems minor but it alters the exercise enough that you're no longer getting the intended benefit.
Keep your legs and torso in a straight line without that hip bend.
Jumping to Advanced Variations Too Soon
This mistake undermines all the others.
When you attempt variations beyond your current strength level, your body finds ways to compensate.
You'll catch yourself holding your breath, bracing excessively hard, or constantly flexing your hips just to maintain balance. These are red flags that you've progressed too quickly.
Master the easier progressions first, build the foundation properly, then move forward when you can hold solid form consistently.
Your 6-Level Progression Roadmap
Progress through these levels systematically.
Don't skip ahead—each stage builds the strength and stability you need for the next.
Level 1: Bent Knee on Floor
Start here if you're new to the exercise or returning from injury.
Both legs stay bent at the knee.
Your top knee, ankle, and foot rest on the bench while your bottom leg remains on the ground for support.
This reduces the leverage on your adductor muscles, making it the easiest entry point.
Focus on maintaining that straight line from your shoulder to your hip without worrying about leg position yet.
Level 2: Bent Knee Elevated
Now you're removing that ground support.
Place the inside of your thigh near your knee on the bench with both legs still bent.
Lift your bottom leg off the floor and press it against the underside of the bench.
Hold this position isometrically for 10-30 seconds.
You'll immediately feel more demand on your adductors and core compared to Level 1.
Level 3: Short Lever
This is where things get interesting.
Your top leg stays bent with your foot, calf, and knee resting on the bench.
The change? Your bottom leg straightens and elevates.
Lengthening that bottom leg increases the difficulty substantially.
You're working with a longer lever arm, which means your muscles work harder to maintain the same position.
Level 4: Full Copenhagen Plank
The classic version. Both legs extend completely straight.
Your top leg rests fully extended on the bench, using the internal part of your foot for support.
Position your ankle a few inches above the bench surface—this gives you optimal leverage and control.
Your bottom leg hangs suspended in the air with no support whatsoever.
This is what most people picture when they think of the Copenhagen plank, and it demands significant adductor and core strength to hold properly.
Level 5: Dynamic Variations
Static holds built your foundation.
Now add movement.
Lower your hips toward the ground in a controlled motion, pause briefly at the bottom, then squeeze your obliques and adductors to lift back to the starting position.
You're working through lateral flexion and extension, which adds a powerful oblique stimulus on top of the adductor work.
Each repetition should be deliberate and controlled—no bouncing or momentum.
Level 6: Elite Progressions
Once dynamic variations feel manageable, you have several paths forward.
Elevate your top leg higher to increase your range of motion.
Add light weight on your hip and progressively increase the load over time.
Use suspension trainers like TRX for added instability that forces your stabilizer muscles to work overtime.
The most challenging option: perform an active knee drive with your bottom leg while maintaining perfect alignment and trunk stability.
This tests every aspect of your strength and control simultaneously.
Move to the next level only when you can hold perfect form for the prescribed time or reps without compensation.
Rushing the progression gives you nothing but poor movement patterns.
Programming Guidelines for Maximum Results
How you program this exercise determines whether you see real results or just go through the motions.
Your training goal dictates your approach.
For Injury Prevention and Strength Development
If you're an athlete looking to bulletproof your groin and hips, work up to 1-3 sets of 12-15 repetitions.
Train 2-3 times per week for at least 8 weeks.
This protocol follows the research that demonstrated increased eccentric hip adduction strength and decreased injury risk.
The 8-week minimum isn't arbitrary—it's how long it takes to see measurable adaptations in your adductor strength.
For General Fitness Integration
You don't need to be an athlete to benefit.
Perform 2-3 sets of 6-15 repetitions, 2-3 times weekly as part of your regular program.
Slot it into your core circuits or tack it onto the end of leg day when your stabilizers are already warmed up.
This approach builds functional strength without requiring a dedicated training block.
Starting From Zero
Complete beginners should begin with 2-3 rounds of 10-15 seconds per side.
Build gradually to 30-45 second holds.
Once 45 seconds feels manageable without form breakdown, you have two options: increase the duration further or advance to the next progression level.
Most people find better results moving to a harder variation rather than holding easier versions for extended periods.
Isometric Hold Standards
Hold the top position for 15-60 seconds depending on which progression level you're using.
Perform 3-4 sets per side with adequate rest between sets.
Your rest periods matter—rushing from set to set with fatigued muscles leads to compensation and poor form.
Give yourself enough recovery to maintain quality.
Tempo and Tension Requirements
Each repetition demands slow, controlled movement.
Never rest on the ground between reps during a set—maintain continuous tension throughout.
This constant tension maximizes muscle engagement and prevents you from using momentum to cheat the movement.
If you need to touch down between every rep, you're working at too difficult a progression level.
Where It Fits in Your Training
You have flexibility in how you integrate this exercise:
- Dynamic warm-up approach: Use 2-3 sets of 15-30 seconds on each side before your main workout to activate your adductors and lateral core
- Core circuit integration: Include it alongside planks, dead bugs, and other core exercises in a dedicated circuit
- Workout finisher: Add it after your main lifts when you're already warm and ready to target your stabilizers
Perform hip mobility exercises before you start.
Warming up your hips improves your range of motion and prepares the muscles for the loaded position.
Cold adductors don't respond well to this exercise.
Alternative Approaches for Adductor Work
If you can't perform Copenhagen planks yet or want additional adductor training, you have options.
Use the seated hip adduction machine at your gym. Lie on your back and squeeze an object isometrically between your knees or ankles.
Perform side-lying leg lifts with bodyweight or ankle weights.
These alternatives build adductor strength through different movement patterns, though none replicate the functional positioning of the Copenhagen plank.
The key to results isn't finding the perfect program—it's following a solid protocol consistently for long enough to see adaptations.
Pick the approach that matches your goal, execute it properly, and stick with it for at least 8 weeks before evaluating your progress.
Conclusion
The Copenhagen plank delivers results when you respect the progression and prioritize form over ego.
Start at a level that lets you maintain proper alignment, train consistently 2-3 times per week, and advance only when you've truly mastered each stage.
Give it 8 weeks of focused work and you'll build the adductor strength and lateral stability that most training programs completely miss.
