The 5 Form Mistakes I See All the Time (+ how to fix ’em!)

I wish it was socially acceptable to go up to a stranger at the gym and correct their form. I’m fully aware that that would be a totally dick thing to do, and I would certainly slap a stranger if they did that to me, but god it’s SO difficult to resist correcting someone’s poor form when it just looks painful.

Since I can’t approach strangers at the gym to correct their form, here are the most common form mistakes I see both at the gym and in group fitness classes and how to fix them.


5 Super Common Form Mistakes

1. Lunge: “The Knee Injury”

lunge incorrect

How to correct it: Whenever you’re in a lunge, make sure your knee is stacked over your ankle, creating a 90 degree bend in the front knee.

This is not only true in lunges where you step back, but also a key part of Warrior II in yoga. Make your 3rd grade math teacher proud (or whenever it is we learned about right angles) and hit that 90 degree angle!

lunge correct

2. Plank: “The Neck Crane”

plank neck crane

Usually the cause of the “neck crane” in plank is because you’re checking yourself out in the mirror. Not that there’s anything wrong with that in theory, but it does mess with your form!

How to correct it: Instead of straining your neck to look forward at the mirror, pick a spot diagonally in front of you to stare at. Your head should be natural extension of your spine.

plank correct

3. Plank: “The Butt-Up Plank”

the butt-up plank

How to fix it: If you’re guilty of letting your butt hike up in plank (both forearm and straight arm variations,) chances are you’re not squeezing BOTH your glutes and core in plank plus you’re letting your back round. In the perfect plank, I should be able to balance a glass of water on your sacrum. Your butt should be in line or just below shoulder height.

If you feel your booty starting to ride on up, check yourself before you wreck yourself. BUT beware, the butt-up plank has an equally as ugly (and incorrect) brother… the droopy back plank.

4. Plank: “The Droopy Back Plank”

the droopy back plank

Do not, I repeat, DO NOT let your belly sag in plank. I don’t care how cute you think your butt looks, DON’T DO IT.

How to fix it: Think about sucking in your core AND tucking your tailbone under. You want to take away that curve in the spine, almost like you’re getting punched in the stomach. Don’t forget to engage both your core AND your glutes.


correct plank form

5. Squat: “The Wobbly Knees”

the wobbly knees

How to fix it: If you’re struggling to keep your knees tracking over your toes, I highly recommend using one of those mini bands around the meaty part of your calf. Practice really pressing your knees apart during all parts of a squat. Since we spend so much of our day sitting, our butts are surprisingly lazy and don’t know how to “turn on.” This can cause your knees to accidentally knock in during squats. Waking up that butt with mini band exercises really helps!

In a squat, there are a few alignment cues I like to keep in mind:

  • Put the weight in your heels! You should actually able to wiggle your toes in a squat.
  • Make sure your knees are tracking in between your big toe and second toe.
  • Whether or not you have a band around your calves, really think of pressing out your knees instead of letting them knock in.

correct squat


YOUR TURN: What other common mistakes I should add to the list? And for fellow fitness professionals out there, any other form cues you like to use when you see these issues in clients?


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