Tag Archives: anatomy


a baby sits in the shape of a W

W-Sit Position


A baby sits with legs straight

Sitting with Legs Extended

When babies learn to crawl, they stop and sit so their hands are free to play with a toy.  One common pattern of sitting that emerges in infancy is the W-sit.  The name of this position comes from the idea that if you take a photo from above, the shape of the legs looks like the letter “W.”  Look at the top photo of baby Sayid in the W-sit position.  His hands are free to play with toys while he sits.  However, Sayid’s mother knew that the W-sit position was not the best for him, so she requested a virtual lesson with Stellar Caterpillar.  After one virtual lesson and some daily guidance from his mother, Sayid learned to prefer other sitting positions such as the long sitting position which is seen in the bottom photo where he sits with his legs extended out in front of him.  Let’s explore why other sitting positions are preferable for the motor skill development of a baby.


When crawling or walking, babies often just plop down into the W-sit.  It is a quick movement and requires less coordination of the bones and muscles, so it is easier to do than the side sit, butterfly sit, or long sit.  Sitting in this position very quickly accomplishes their goal of sitting down and freeing their arms and hands to play with toys or eat a snack.  Quite simply, babies W-sit because they get what they want quickly!  As they learn other patterns of sitting, baby’s body recognizes the benefits and begins to prefer the other, and developmentally beneficial, sitting positions.  These include tailor sit, butterfly sit, Z-sit, and long sit.  Slowly they drop the pattern of W-sit.


Babies are limited in their mobility as they W-sit.   Their lower legs and pelvis are fixed in a way that is not easily moveable and they are not able to shift their weight from side to side or twist/rotate their torso.  They play with toys on their right side with their right hand and toys on their left side with their left hand.  This does not develop the skill of mid-line crossing (reaching across the body) and does not encourage the development of hand dominance (preferring the use of right hand or left hand). The internal rotation of the hips tightens the hips muscles and actually makes it more difficult to sit in the other positions as time goes on.  This leads to the W-sit becoming a habit.  Over time if the child continues to W-sit as she grows it may lead to orthopedic problems such as hip dislocation or knee pain.


The key to avoiding the W-sit is to guide baby to learn other choices for sitting.  Baby will feel the advantages in these other positions and choose them over the W-sit.  Some babies will learn the other sitting positions right away, the first time you show them.  Other babies will require much repetition until they finally find them on their own.  And a few babies will need even more repetition to find the position.  What is important to remember is that baby will learn to choose other ways of sitting and will enjoy them very much as they discover improved mobility.  They can grab toys all around them in these other positions due to the ability to rotate their torso and reach across their mid-line.

Observe baby Sayid in the above photos. In the top photo (in the view taken from above his head), he is in the W-sit and can turn only his head to the side.  His torso is fixed in position.  In the bottom photo of Sayid in the long sitting position, he is able to turn his torso toward the camera to smile and to reach toward his mother.  The more he sits in this new position, the more he will discover he can turn his torso and reach to the side.  His movement will develop with more skill.  By teaching baby alternate ways of sitting that offer her more mobility, baby will develop motor skills with more strength, balance, and coordination.  This will enhance more advanced motor skill development such as walking, running, climbing, dancing, and more.






a baby sits up with good posture


Baby Rochel began Stellar Caterpillar lessons when she was just a few months old.  Her favorite part of the lessons were the proprioception exercises.  These are the exercises where we squeeze various parts of the body as we say the name of that body part.  For example, while squeezing her leg I would say, “Rochel, this is your leg.”  Her mother practiced these exercises with her everyday.  They are a fun game for babies.  For babies, these exercises are similar to the feeling they get when being swaddled with fabric.  The firm yet gentle pressure of your hands on their body feels secure just like the feeling of the swaddling cloth when it is pressing against their body.  Rochel’s favorite body parts to identify through touch were her ribs and her toes.

Today Rochel is three years old and attends preschool.  I had the chance to talk with her mother recently and she proudly told me a story about Rochel.  “Last week at preschool, Rochel fell down.  The teacher asked her is she was OK and Rochel told her that her “ribs hurt.”  The teacher asked me, “How does 3-year-old Rochel even know she has ribs?”  I explained to her that we learned exercises to do with her when she was a baby that taught her the names of her body parts.”  Most 3-year -olds would refer to the area of the ribs as their “side” or just say “it hurts here” as they touch it.  To identify the ribs by name shows quite a bit of learning.  This is why Rochel is one of our superstars!!!

Even though babies may not be able to speak yet, they can learn far more than we can understand.  Through the use of the sense of touch, the spoken name of the body part, and with repetition, Rochel and many other babies develop a very clear awareness of their body and the names of their body parts.  The development of body awareness is an important part of motor skill development.  Through these exercises, many babies can develop a strong sense of body awareness just like Rochel.


baby in hands and knees crawling position

A seven month old baby demonstrates the hands and knees crawling position. The knees must bend to place the knee joints under the hip joints.


Recently we received this question from one of our readers in Texas:

“My daughter is 8 months old.  We are trying to help her learn how to crawl.  It seems she has the arm strength but will not bend her knees.  If we put her into the crawling position to show her, she will straighten out her legs and lay on her tummy. Also, she does the same thing while going from a standing postion when we sit her down the locks her knees. Is there anything we can do to help her?  Thanks, I love reading your website!”

This is one of the most common questions asked by moms in classes and through my website.  Baby seems to resist putting her knees on the floor when mom tries to put her in the hands and knees crawling position.  This mom is not alone with her question!  It is wonderful that this mother would like to learn some parenting tips for teaching baby to crawl.  Simple activities at home on a daily basis are both a fun form of baby play and beneficial for baby motor skill development.  Let’s take a look at three developmental activities for baby.


One of the ways that babies get into the hands and knees crawling positon is by lifting their pelvis up and bending their knees to bring them under their hip joints.  The plank positon (or push-up position) is a straightening of the legs by stiffening the knees.  This is the opposite action of what baby needs to do with her knees.  Before baby can learn to bend her knees and ultimately put them on the floor beneath her hip joints, she must have a clear feeling of the knee joint itself.  Gentle proprioceptive activities improve the awareness of body parts for baby.  We recommend tapping the knee while saying “This is your knee,” and gently squeezing the knee and holding the squeeze for a moment while repeating “this is your knee.”  Observe baby and see if she is paying attention to what you are doing.  She will become quiet and feel what you are doing.  This is how to improve baby’s awareness of the knee joint for the motor skill development of crawling.


Once baby has an improved awareness of her knee joint, you can improve her awareness of the knee joint action which is bending and extending.  After the tapping and squeezing recommended in crawling tip #1, put her on her back.  continue tapping and squeezing the entire leg while saying, “This is your leg.”  Repeat with the other leg.  Then hold one leg and gently bend it in toward her chest and slowly extend it toward the straight position.  Do not force this movement.  If her leg does not move easily, baby’s muscles are stiff.  Focus on just the tapping and squeezing for a few days and that will help the muscles to relax.  The bending and extending of the legs shows baby that she can both bend and extend the leg.  Soon she will soon bend her leg more frequently on her own.


Baby play time can include a fun game of playing a box like a drum.   Place a cardboard box upside down with baby on knees in front of it.  Gently press her knees down so she feels the pressure of putting the knees on the floor, which you would like her to learn to do on her own.  Play the box like a drum with your own hands, pause, then invite baby to drum.   Create a call-and-response type of game where your hit the box “rat-a-tat-tat” and then wait until she hits it “bop-bat-dat.”  Go back and forth taking turns.  This gives baby an experience of being on her knees.  She will feel comfortable in this position and choose it more easily, facilitating the development of the hands and knees crawling position.



a baby plays with her hand on her foot

Donna Eshelman shows baby how to bring her feet together.

A baby plays a developmental activity of clapping her feet.

A teacher shows baby a game with clapping her feet.


One of the most important motor skill connections in the development of a baby is the discovery of touching the feet with the hands.  Usually baby first learns to touch her right foot with her right hand and left foot with left hand.  Later, she discovers how to reach across her midline (the line diving her body in half between right and left sides) and touch her right hand to her left foot or her left hand to her right foot.  She will enjoy this new skill and hold her foot and move it around.  Sometimes she will grasp one foot with both hands as she bends and straightens her leg.


You can entertain baby with some developmental play by clapping her feet together.  When you bring the feet together with a clap, make a funny sound the moment the feet touch.  You can also make a facial expression such as a big smile with wide eyes to show her this is an important moment when the feet touch.  This means that you will communicate the importance of the moment the feet touch through many senses–through touch with your hands, hearing with your voice, and sight with your facial expressions.  Baby will be both intrigued and amused.  This is a new sensation–bringing both feet together in the air.  Touch the feet together, then OPEN and CLOSE the feet.  Soon you can involve her hands and place one hand on one foot as you play this game.  Continue making sounds and facial expressions as you touch her hand to her foot.  This brings her attention to her hands and feet and increases her proprioception of these body parts.  Although she may not clap her feet together herself, she may explore the contact of her hands to her feet.  When you have no toys with you, this is a wonderful activity for baby play.


a baby rolls from her back to her tummy


One of the early motor skills baby learns is rolling.  This skill can be discussed by breaking it down into moving from the back to the belly, from the belly to the back, and the connection of those two into one full log roll all the way around to the starting position.  For this post, we will look at the movement from the back to the belly.  There are a few ways to initiate every skill, and we are examining the various possibilities for initiating this new skill.


When asking the question, “How can I teach baby to roll,” consider observing how babies begin the movement.  One of the popular ways that a baby begins to roll is bending up one leg toward his chest and then moving it to the side.  The leg is connected to the pelvis at the hip joint, which is one of the heaviest bones in the body.  As the leg moves far enough out to the side, the pelvis tilts and soon the weight of the pelvis takes baby onto her side and into the motor skill of rolling.  (See photo above.)  Baby learns this skill as she is lying on the floor kicking and moving her legs around.  The movement is just an exploration, an improvisation, and suddenly she moves one leg far enough to the side that she is pulled onto her stomach.  It was an accident! She was not intending to roll, it just happened.  What a wonderful discovery for her.  She figures out how to repeat it many times so it becomes an skill and not just an accident.


Mastering the motor skill of grasping and reaching is integral to the motor skill development of rolling.  Often the roll is initiated by a reaching action.  That is a reaching action with the intention to grasp something, usually a toy.  The arm is connected to the torso or ribcage at the shoulder joint.  When baby reaches her arm across her body, the ribcage begins to move and she tips into the beginning of a roll.  Often the arm and the leg on the same side of the body will move a the same time and in the same direction to facilitate the baby turning onto her tummy.  Some babies develop a habit of quickly pulling their arm back to the side when they begin to move because they are a bit startled.  When they pull the arm quickly back to their side they roll back onto their back.  The pulling action of the arm backward pushes the ribcage backward and baby rolls onto her back again.  By placing a toy nearby, baby now has an intention to grasp something and is less likely to pull the arm backward.  Providing the motivation for the action is always key.  She wants that toy!


Another possible initiation of the skill of rolling occurs when baby is on her back and someone is sitting up above her head.  In order to see them, she rolls her head to one side and then looks up a bit toward the person.  This action shifts her weight just enough in her torso that she can roll onto her side from here quite easily.  This movement of initiating the roll with her head often involves the action of reaching as well.  This pattern often evolves out of baby’s curiosity to see something that is located behind her.  Read more on the skill of rolling by clicking on one of our posts below:



A baby receives motor skill instruction through hands-on guidance by her teacher.


How do we know where we are in space?  Through pressure.  When you sit on a chair you feel the contact of your bottom against the seat of the chair and your feet against the floor.  When you recline on the sofa to watching TV, you feel the pressure of the back of the legs, pelvis, torso, shoulders, and head against the fabric on the furniture.  These sensations of pressure tell you that you are lying down.  This ability to feel orientation in space is called proprioception.  We have receptors in the cells of our skin, muscles, joint, and bones that respond to the pressure of touch by sending signals to the brain to pay attention to the area receiving the touch.


For baby, she has been in the watery environment of the womb for many months.  Water creates pressure and helps baby feel her body more clearly.  After birth, parents often swaddle baby to recreate the secure feeling in the womb of the pressure of water on baby’s body.  The pressure of the material snuggly wrapped around her body is comforting because it helps her feel where she is in this new airy environment.  Her new environment gives less sensation to the skin, bones, and muscles than the watery environment of the womb.   Babies enjoy swimming lessons because the water is familiar to them and the pressure feels comforting.  Benefits of baby swim lessons include gentle strengthening and improved proprioception as she feels each body part very clearly as it moves against the pressure created by the water.  Learn how to swaddle your newborn and locate a school offering swim lessons for babies to develop your child’s proprioception.


Baby’s brain sends the signals to her muscles to move.  As baby learns her motor skills, touch is very informative. The pressure of your hand on her leg clarifies that particular body part in her brain.   When she feels her leg more clearly she can use it in an improved way.  For example, after tapping and gently squeezing baby’s leg she may begin to kick that leg with more vigor.  An activity to try at home is to gently tap each of baby’s limbs in a rhythmic way and name them for her.  If repeated regularly, she will like it and it may calm her when she is fussy.   Just remember, through the sense of touch information is being sent to the brain where her motor skills originate.


The baby in the photo at the top of the post is on her stomach.  She feels she is on her stomach because of the contact of her abdomen and chest with the floor.  When her teacher puts her hand on baby’s back, baby feels that part of her body more clearly.  She also feels where she is in an improved way because of the contact to both sides of her torso, front (against the floor) and back (from the teacher’s hand).  She feels more secure when she feels the dimensionality of her torso rather than only one side.  This technique can be used to improve motor skill activities such as tummy-time.   When baby is on her tummy you can tap her back so she feels more secure and will learn to lift her head.  Simple hands-on skills can be learned to guide baby through each motor milestone.