Common Form Mistakes in Plank

A lot of the core work in Lagree Fitness is plank-based, so it’s by far the exercise I see the most in teaching group fitness. I have seen some very impressive (and long!) plank holds…but I’ve also seen just about every possible way one could imagine to do them incorrectly (haha). And I don’t mean that condescendingly at all—I used to do them with a pelvic tilt (more on that to come) myself.

Planks seem simple, but like with most exercises, proper form is key for them to be effective. And since countless moves utilize this position in one way or another (push ups, burpees, mountain climbers, etc.), it’s an important one to get right. As a way to explain how to do them correctly, I thought it’d be helpful to go over some of the most common form errors I see when teaching.

There’s your overview, now let’s break them down…

Pelvic Tilt (aka The Booty Pop)

In this error’s defense, it does make you look like you’ve got some killer Kardashian-esque curves. I’M KIDDING. Don’t do this! This postural imbalance is common with a lot of people (not just when planking) because sitting down for long periods of time can cause a tightening of the hip flexors, making us tilt our pelvis and arch the low back. If you look back at some of my original blog posts (back in the days before the PT cert and teaching), you can spot me making this mistake here and there. My pelvic tilt is a muscle imbalance I’m still working on.

If you’re doing this “booty pop” in plank, here’s your cue to correct it: Get into your plank position and then imagine you’re trying to button and zipper up a tight pair of jeans. Engage the low abdomen, pull the belly button in and tuck your tailbone. Another way to think of it: Close your rib cage. Don’t let the ribs fan out; squeeze your core, straighten out the low spine, and close your rib cage in like a girdle.

Over-Engaged Chest

This form error can be spotted by a rounding of the shoulders. It’s very common to have an overdeveloped frontside and a weak posterior body, so oftentimes we’ll overcompensate for a lack of strength in the back and core by propping ourselves up in plank using our chest (and only our chest). If you have a slight hunchback going in your plank, you may be doing this.

To correct it, you need to relax your chest—chancing are, you’re clenching your pecs for dear life. Don’t disengage your chest altogether, but think of bringing your upper back to a neutral position where the spine is level with the shoulder blades; not rounding up above them.

“Heavy” Spine

This one usually goes hand-in-hand with the pelvic tilt error. It’s hard to demonstrate with pictures while wearing a bra and shirt, but it’s essentially just the opposite of the over-engaged chest. In this one, you’re not engaging your chest at all, and your upper back kind of droops down, spine hanging heavy between shoulder blades that are pinching slightly together. Again, we’re trying to find a neutral upper back position, right in between the over-engaged chest and “heavy” spine.

To better demonstrate what’s going on, look at the above picture comparison. It’s a subtle difference, but these pics were taken from the exact same angle. On the left, you can’t see the full racerback of my tank & bra because my back is sunken low in between the shoulder blades (this is incorrect). On the right, I’ve engaged my chest and lats enough to bring my upper back to a neutral position—you can see my shirt laying flat across my back.

Lifted/Piked Hips

We tend to do this one when we start to tire holding a long plank. Don’t let your body come into this piked, upside-down “v” shape! When we do this, we’re shifting the distribution of our body weight and giving our core a little breather—not the point of the plank exercise.

If your butt keeps creeping up into the air like this, think of holding your hips level with shoulder height (probably just below shoulder height if holding a high plank on your hands). From heels to crown of head should be one straight line.

Wrists/Elbows Not Stacked Under Shoulders

In high plank, I usually see the hands are pressed out a few inches in front of the shoulders. In forearm plank, I most commonly see the opposite, where the shoulders are ahead of the elbows. When you’re in a plank, you want whatever joint is on the ground (wrists if in high plank; elbows if in forearm plank) to be stacked directly underneath your shoulders.

I should note that there is a (vey challenging) plank variation where you purposely have your hands on the ground as far in front of your shoulders as possible—I’m not talking about that. I’m talking about those slight weight redistributions we tend to do as we wiggle our way through a long plank hold.

Unengaged Legs

Think of all the ways you start to fidget when you’re holding a plank for a long period of time. Do you ever start to pedal your feet, bending one knee and then the next? Relaxing your knees and having bent legs changes the way our bodyweight is supported in plank.

To keep the correct form, squeeze the quads, right above the kneecaps, straightening out your legs and body. Think of your heels and head stretching towards opposite ends of the room. Strong, straight legs.

Heavy Head or Craned Neck

I usually see the heavy head at the end of class when half my students want to kill me. The human head is heavy, but you want to keep a neutral neck so that your spine is straight, from tailbone to skull. Don’t let your head hang at your chest, but also don’t crane your neck so that your gaze is upward. Think of looking at a spot on the floor a few inches in front of you.

And since we’re on the topic of planks, did you see that

a guy in California held a plank for 5 hours and 15 minutes last weekend?! And to think I’m pumped when I make it 5 minutes…

Fellow PTs and fitness instructors—any other errors you want to add to this list? And, perhaps more importantly, any cueing tips you want to add for adjusting into correct plank form?