Is W-Sitting Bad For Child Development?

**Note this post was originally written and published in 2015. While my recommendations remain the same, I've edited the personal/parental portion to add my experience parenting my third baby with low muscle tone and some muscle weakness who W-sits to my already published experience of having 2 typically developing kiddos who used this position.

I always say here on the CanDo Kiddo blog that I'm a new parent just like you - alongside you in the trenches of sleepless nights and diaper blowouts. So here it is, friends, a fellow mom confession:

My baby W-sits.

*GASP* the horrors! I'm a pediatric therapist and my child sits in one of the positions most despised by Physical Therapists. Parents have asked me about W-sitting in the past and I've given my professional answer, which tends to be a more moderate view than some other therapists (I'll share some links at the end of this post with other perspectives on W-sitting). Today I can add to that professional answer my personal "mommy-take" on this topic. Let's begin at the beginning:

Why Is My Child W-Sitting?

Common reasons why children W-sit that SHOULD BE ADDRESSED:

Limited core strength: The W-sitting position gives kids a wider base of support. This may be used to compensate for weak belly and back muscles that make it tiring or challenging to sit in other positions.
Muscle tightness: Tight muscles of the legs (particularly the hamstrings on the backs of the thighs) and hips can lead a child to prefer a W-sitting position over long sitting (legs stretched out in front) or tailor sitting ("criss cross applesauce" position).
Low muscle tone: We often talk about muscle strength, which refers to active, contracted muscles. Muscle tone is the resting state of the muscles and is controlled by the brain. Some kids have what's called hypotonicity, or low tone. When they aren't actively firing their muscles, these kids have floppier, softer muscles that have a harder time holding their bodies upright. W-sitting is very often seen in kiddos with low muscle tone.
Poor trunk rotation skills: If a child is lacking the ability to twist the torso adequately, he will struggle to transition into and out of a sitting position on his bottoms and may compensate by W-sitting. See photos of trunk rotation and learn how to play to encourage it here.

One of the factors that can contribute to baby having limited core strength and poor trunk rotation is too much time spent in Baby Holding Devices ; this may be why we seem to see more W-sitting in kids today. Children begin developing these important foundations of strength and movement skills in infancy - EARLY infancy. Try to follow the Rule of 2 and 15 to limit your baby's time in baby gear and help give him the healthiest start possible.

Here's a great post about "the container shuffle" that many babies today experience and how it can contribute to difficulties with transitional movements, like those required to get into and out of a good sitting position.

Common reasons why children W-sit that are TOTALLY NORMAL:

Fine motor control: Children (and adults) get the most coordinated, controlled movements of the hands and fingers when they are really steady through the body and arms. It is normal that at times your child will assume the most stable sitting position possible when completing challenging fine motor tasks.
Flexibility: Let's face it, most adults don't W-sit in part because we can't. Most children have the flexibility to easily assume a W-sit position and so they likely will at times.
Convenient transitions: This one applies particularly to babies. The quickest way to find a seat while crawling is to plop the bootie down into a W-sit. Sure, your baby could rotate and get into a nice seated position but when the dog barking grabs her attention mid-crawl, it makes sense that she finds the quickest transition possible to sit up and check things out. Similarly, if your baby plays in a tall kneel position (balancing on the knees, shins and tops of feet with bottom lifted), she'll likely drop down and back to sit on her calves and possibly to W-sit. It's a natural, easy transition.

So Why Is My Kid W-Sitting?!

To get to the bottom of why my baby is doing, well .... anything, I put my detective hat on and look for clues. Here's my OT Mommy thought process about my 1st kiddo (which also applied to my second):

I've wrestled my kid on the changing table and watched him climb the furniture enough to know he's got great core strength. Despite W-sitting, he is able to sit in a variety of positions. I don't see signs of hip and leg muscle tightness such as feet that turn in or out, abnormal walking pattern, inability to sit with legs out and knees straight, or back rounding when sitting (which can reflect a pelvic compensation for tight hamstrings). I'm not concerned about his muscle tone because his muscles feel firm to the touch even at rest (underneath that cute baby fat, of course) and he's never felt floppy or had trouble staying in upright positions.

So, I can rest easy that my first 2 kids are probably W-sitting for very normal reasons.

But here's where this old post gets a big addition. My third baby DOES have low muscle tone and core weakness. My mommy therapist eyes see it in many ways but here are a few... she has very lax / hypermobile / floppy hips and ankles. She didn't press up through extended arms in Tummy Time without a lot of mommy therapy. She often held her head fully lifted in Tummy Time by doing what's called "cervical stacking" where the base of her head basically rested on her upper back. She still had some head lag when pulled to sit at 5 months. She didn't bear her full weight through both legs until nearly 8 months. And now that she's crawling (the result of a LOT of mommy therapy), she transitions from her belly through a full split to sit with very wide legs OR from crawling to W-sit or (her favorite) a half-W-sit (one leg extended out to the side and one leg bent with foot beside hip).

You can think through a similar process with your kiddo. Try to think of other activities or opportunities for you to observe and watch for the problematic causes of W-sitting I listed above.

And if you have any sneaking suspicions that your baby is a little weak or tight or that there may be an underlying reason for W-sitting, I would recommend getting a Physical Therapy evaluation. Even GREAT pediatricians tend to see motor development from a 20,000 foot view based on a few general questions. For example, my third baby passes the screening questions - Does baby bear weight through his feet by 9 months? Can baby sit upright without hand support by 9 months? But that doesn't mean that all is right in the quality of her movements and strength. A pediatric Physical Therapist will have laser-focused, skilled eyes to see exactly what's going on with your kiddo if you have concerns.

How Will This OT Mommy FIX Her Kid's W-Sitting?

With my first 2, totally typically developing kiddos I didn't.

I know, I know, my fellow therapists might be throwing things at the computer screen and groaning right now. But hear me out....

I see W-sitting as potentially harmful for a child's development IF:

there is an underlying problematic reason for W-sitting that isn't addressed
a child has known orthopedic, neurological or developmental challenges
a child extensively W-sits (Note: MANY children W-sit when watching television and other screen media. Given the fact that the average American preschooler has over 4 hours of screentime a day, I'd consider that excessive W-sitting!)

But I am working HARD to keep my 3rd baby - my low-tone, decreased core strength kiddo - out of W-sitting.

The biggest way that I'm doing that is through strengthening. With the help of a pediatric Physical Therapist, Maeve has a fully developed daily home exercise program to strengthen her core (belly and back) muscles, the muscles that stabilize her hips and her leg muscles. We're working on guided movements and positions that will decrease her reliance on W-sitting.

So for typically developing kiddos, some W-sitting as one of several sitting positions isn't going to deform bones and joints, tighten hips, lead to a weak core, etc. For those babies and toddlers, active unrestricted in baby gear, not spending time in front of screens and getting outside every day is enough to overcome any ill-effects of W-sitting for a few minutes a day.

But for babies with underlying issues that are contributing to W-sitting, a little intervention can go a LONG way toward healthy sitting and optimal movement.