When it comes to core exercises, the focus is often on the “six-pack” muscles in the front of your body (the rectus abdominis), but that leaves the all-important obliques out of the equation. These core muscles that run along your trunk on either side are responsible for much more than the proverbial snatched waist. Obliques contribute to your balance and stability, as well as help you rotate, twist, and pivot—important factors for sports, including running, tennis, soccer, and everyday life. 

One of the best exercises to target your obliques is the side plank. This anti-rotation, isometric exercise requires you to stabilize as you strengthen to prevent wobbling or toppling over. And it’s so much more than a core exercise. Similar to the traditional plank, the side plank requires you to fire up muscles from head to toe. Here’s more on exactly how to do a side plank, what muscles you’ll work, and some side plank variations to inspire you to get started.

The Benefits of Doing Side Planks

It’s pretty obvious, but it deserves repeating: Side planks help to strengthen your core. But remember, your core goes well beyond your “abs” and encompasses muscles from your back down to your pelvic floor. 

“Side planks help to strengthen your core—from your shoulders to glutes,” says Peloton instructor Kirra Michel. Because side planks have a smaller base of support compared to regular planks, they’re a fantastic way to improve your balance and stabilization, as well as proprioception (awareness of your body in space), according to Kirra. 

Isometric exercises (such as side planks), which require you to hold a static position while your muscles are under tension, can also help build muscular endurance, she adds. Aim to increase how long you hold your side planks incrementally to push your time under tension longer and longer.

“Side planks are great for working your lateral chain of muscles that help with single-leg activities such as balance, walking, running, using stairs, or side-to-side movements,” says Ryan Chow, physical therapist and founder of Reload. Front planks, on the other hand, only train muscles in the sagittal plane (the front and back of the body), and don’t help as much with balance or lateral control, Chow adds. 

Muscles Worked By Side Planks

The muscles worked by side planks help with many actions we do in everyday life and fitness, Kirra says. Here’s a breakdown of the main muscles involved in a side plank, according to Kirra and Chow:

How to Do a Side Plank

It’s helpful to get into a traditional plank position on both hands before pivoting into a side plank, as this ensures every muscle is properly engaged and you feel sturdy in the pose, Kirra says. 

Side Plank Variations 

Forearm Side Plank

Any side plank, including the below plank variations, can be performed on your forearm instead of your palm. This is a great choice for anyone with wrist or shoulder issues, or if you’re simply looking for a broader base of support.

Modified Side Plank

Lie on your side with both legs bent and stacked, and your palm on the ground directly beneath your shoulder. Lift your hips as you straighten your arm. Your body should form a straight line from head to knees.  

Side Plank Clamshell

Lie on your side and set up your legs for a modified side plank. Lift your hips and straighten your arm as you simultaneously externally rotate your top hip to open up into a clamshell position. In one smooth transition, reverse the movement to return to the starting position. 

Staggered Leg Side Plank

Lie on your side with both legs long and your palm on the ground directly beneath your shoulder. Lift your hips as you straighten your arm. From this position, place the top foot in front of the bottom foot. This creates a more stable base compared to stacking your feet.

Tree Pose Side Plank

Lie on your side with both legs long and your palm on the ground directly beneath your shoulder. Lift your hips as you straighten your arm. From this position, slide the foot of your top leg to the inseam of the opposite thigh, as you reach your knee toward the ceiling.

Side Plank Leg Lift

Lie on your side with both legs long and your palm on the ground directly beneath your shoulder. Lift your hips as you straighten your arm. From this position, lift your top leg to hover at about hip height. (For a bonus burn, pulse the top leg up and down.)  

Side Plank Hip Dips

Lie on your side with both legs long and your palm on the ground directly beneath your shoulder. Lift your hips as you straighten your arm. From this position, drop your hips toward the floor without letting them touch the ground, then immediately lift your hips back to the starting position. Be mindful not to drop through the shoulder and maintain control throughout the dip. 

Copenhagen Side Plank

Lie on your side with the inner edge of your top foot resting on an exercise bench or similar sturdy base. Your bottom leg should be stretched long beneath the bench, and your palm should be on the ground directly beneath your shoulder. Lift your hips as you straighten your arm and hover your bottom foot off the ground.

Side Plank Form: Mistakes to Avoid

As fatigue settles in, you may notice that you start to sink at your shoulders or hips, Kirra says. Aim to keep your body in a straight line and weight evenly distributed. You may also find that your hips are tilted toward either the ceiling or the ground rather than directly forward, she says. 

Another common mistake? “Having a deep arch in the lower back, rather than activating the core and pulling in towards the midline of the body,” Kirra says.

One form mistake that’s not just ineffective, but risky, is not stacking your wrist directly beneath your shoulder, Kirra says. This puts undue stress on the shoulder joint. (If you have wrist issues, you can also perform a side plank on your forearm; your fingertips should point forward.)

If you’ve got the hang of side planks, but want to tweak your form to get the most out of the exercise, keep a closer eye on your feet, says Chow. “Most people overvalue the hips being high and don’t pay enough attention to having active feet,” he says. “The harder you push your feet down, the more you get hip musculature to contribute. This also takes a lot of stress off the shoulder and gets more muscle activation overall.”

How to Add Side Planks to Your Workout Routine

Side planks are a great addition to your warm-up, says Chow. Try this: Hold a modified side plank for 30-60 seconds on each side, followed by a progressive variation such as side plank hip dips for 30-60 seconds on each side. Firing up the core, obliques, and glutes thoroughly before the main part of your workout will help improve your performance in moves such as split squats, lunges, staggered stance romanian deadlifts, single-leg squats, running, or jumping, he says. 

You can also incorporate side planks into the main block of work during your everyday exercise routines. Try three to five sets to get the most strength and endurance benefits, says Chow.

If you’ve been training with side planks for some time and feel solid on your form, progress your routine by either increasing the reps, sets, or time. You can also challenge your skills with side plank variations or put together an entire lateral core workout by stringing several exercise variations together for a complete routine. 

If guided workouts are more of your thing, check out the yoga, Pilates, barre, and strength classes on the Peloton App—all of which include side planks. And if you’re looking to feel a burn only in your core? Try a core strength class, where Peloton instructors serve up 5-30 minutes of nothing but core moves.