When you think of core exercises, situps, crunches and planks come to mind. But if you want a well-developed core, you can’t just focus on the core muscles in the front. You need to target your obliques (the core muscles on your sides) — and few exercises do that better than side planks.
Notice we said, “few.” The traditional side plank can be challenging at first, but simply holding a side plank for longer duration loses its luster. Copenhagen side planks take the traditional side plank to a whole new level.
THE ADDUCTOR ADVANTAGE
Popularized by Danish therapists and researchers during their extensive studies on groin injuries, the Copenhagen side plank adds your adductors (groin muscles) into the movement by placing your legs on the top and bottom of a bench. By supporting the weight of your top leg and raising the bottom leg up to the bench, your adductors are forced to fire on all cylinders for a movement that doesn’t just torch your abs, but also tones your inner thighs.
We actually have seven adductor muscles, and it’s important to include them in core exercises for a few reasons. First, to effectively train your core with planks, your pelvis and lower back must remain in a neutral position — not arched, rounded or rotated. Your adductors connect to the pelvis, so if your adductors are weak, it’s harder for your core muscles to keep your lower back and pelvis in the right position.
Second, many people experience groin tightness, not because they need to stretch their groin, but because their groin muscles are weak and overstretched. That feeling of tightness is often your body’s neurological response to weakness; the muscles fire or spasm to prevent stretching to the point of muscle strain. By strengthening your adductors with the Copenhagen side plank, you can reduce groin tightness and the chance of groin strains.
THE COPENHAGEN SIDE PLANK
All you need to do Copenhagen side planks are a bench and your body weight.
The move: Lay on your side with your feet just underneath the bench. Place your top foot on top of the bench, supporting your weight on your instep (make sure the bench is padded, or place an additional pad under your foot). Place your bottom elbow and forearm directly under your armpit, and squeeze your fist tight. Lift your hips off the ground by driving your top foot down into the bench — you should feel the groin muscles of your top leg working hard. Lift your bottom leg up until it touches the bottom of the bench, squeezing your groin muscles. Breathe in through your nose and out through your mouth, focusing on feeling your abs and obliques. Hold for 10–30 seconds, and then repeat on the opposite side.
AN EASIER VERSION: KNEES-BENT COPENHAGEN SIDE PLANK
The Copenhagen side plank is an advanced move that takes time to do correctly, so make the movement easier by bending your knees:
The move: Lay on your side with your hips (not your knees) underneath the bench. Place your top leg on top of the bench with the bench as close to your groin as you can, and bend your top leg so your shin is in line with the bench. Place your bottom elbow and forearm directly under your armpit, and squeeze your fist tight. Lift your hips off the ground by hugging the bench with your top leg. Bend your bottom leg until you’re in a lunge position, and push your bottom foot into the bench. Breathe in through your nose and out through your mouth, focusing on feeling your abs and obliques. Hold for 10–30 seconds on this side, and then repeat on the opposite side.
MAKING PLANK PROGRESS
If your side planks have gotten too easy, the Copenhagen side plank can be a fun and challenging way to train your core. Don’t worry if you can’t do them right away. Keep practicing your regular side planks, and try the knees-bent version before progressing to the full Copenhagen side plank.