|Movement Experiences for Children|
|Instructor:||Dr. Shannon S.D. Bredin|
|Important Course Pages|
Crawling is a fundamental movement skill learned during infant development. Fundamental movement skills are milestones that involve movement of the body in specific patterns during development. Standard crawling is when the infant is propped up on both their hands and knees and the diagonal limbs normally move in coordination . However, crawling can be performed in many alternate ways and some infants do not learn to crawl at all. 
Traditional hands and knees crawling normally comes in two different forms. First is the traditional gait where the infant is on both their hands and knees, which make up around 88% of infants. The other 12% of hands and knee crawlers use a bear crawl technique, which involves the infant balancing on their arms and feet, occasionally using a knee for balance. Other types of crawling are belly crawling techniques, which require less balance control, because their thighs and belly support them. With this being said, infants have many different styles of crawling. All crawling methods consistently show a coordinated, rhythmic pattern .
Locomotor Stages Leading up to Typical Crawling
- Pivot: Alternating, the left and right arm flex and extend cranially while the infant is lying face down with their head lifted up. This causes the abdomen of the infant to pivot back and forth.
- Low Creep: The abdomen is in contact with the floor while the arms are either extended or flexed. The legs are flexed alternatingly.
- High Creep: Arms are both extended while legs are both flexed. The abdomen is slightly lifted and head is lifted.
- Rocking: Arms are both extended while legs are both flexed. Abdomen and chest are both lifted and the infant remains in one rocks forward and backward.
- Crawling: Arms both extend caudally then cranially and legs flex alternately. Opposing arms and legs move simultaneously. Abdomen is raised and head is up.
Progression from Crawling
The more time an infant spends crawling, the more efficient and faster they become.  Crawling infants also dedicated less attention on keeping balance as their efficiency increased – this allowed them to concentrate more on their surroundings and cognitive functioning . Experienced crawlers were found to be able to crawl while carrying an object. Carrying an object did not affect the infant’s chance of falling; in fact, carrying an object was noted as improving their balance. Carrying objects while crawling also helped the infants multitask – they learned to support their own body weight while holding or pushing an object at the same time . Karasik et al. studied the relationship between crawlers carrying objects and onset of walking. They found that if infants carried objects while crawling by the age of 11-months-old, they were more likely to by the age of 13-months-old . Crawling is a precursor to walking in children, although if the infant feels that their balance or safety is in danger, they may revert back to crawling as their means of locomotion until they feel safe again. 
Many different factors affect the way an infant crawls. Different styles of clothing or accessories may inhibit crawling movements in infants. In the late 1800s and early 1900s, certain dresses and clothing did not allow children to use standard crawling methods; therefore abnormal crawling styles emerged and flourished. Other factors influencing crawling styles include the substrate or slope that the infant is crawling on . Another constraint for infants to crawl is due to rise in parents putting their infants to sleep on their back in order to reduce the risk of sudden infant death syndrome. This leads to less time that an infant is spending on their stomach or rolling over, which then inhibits the natural progression of a child laying on their tummy then getting up on their hands and knees to crawl. Infants who slept in the prone position crawled faster than infants who slept in the supine position . Patrick et al. found that the nervous system had limiting factors on the coordination patterns of infants crawling .
How to Facilitate Crawling
Tummy time is when an infant is spending time in the prone position. Parents can facilitate crawling by exposing their child to the adequate amount of tummy time. Tummy time can take place throughout the day, some examples for parents to try are: lying your child on the floor while you fold the laundry beside them, providing soft support under their tummy during their tummy time, and carrying your child in a sling or front body carrier . Tummy time also helps the infant strengthen the muscles of their neck and promotes the movement on arms and legs, which also helps promote crawling. Pitman also encourages parents to practice tummy time while the infant is rested and well fed.
Crawling and Body Dimensions
Chubby children tended to crawl at later ages than slimmer and proportioned children: overall chubbiness has a negative correlation crawling onset age. Crawling onset age has a positive correlation with weight, height, and leg length. 
Mothers have different expectations for their infant to crawl. When mothers are asked to estimate their child’s performance, they consistently overestimated the performance of boys and underestimated the performance of girls. Although there is a gender bias for mother’s expectations, boys and girls have identical motor performances during infancy. The parent’s expectations may contribute to the further development of the infant .
- Culjak, Z., Miletic, D., Kalinski, S., Kizic, A., and Zuvela, F. (2014). Fundamental movement skills development under the influence of a gymnastics program and everyday physical activity in seven-year-old children. Iranian Journal of Pediatrics, 24: 124-130.
- Patrick, S., Noah, J., and Yang, J. (2012). Developmental constraints of quadrupedal coordination across crawling styles in human infants. Journal of Neurophysiology, 107: 3050-3061.
- Adolph, K., Vereijken, B., and Denny, M. (1998). Learning to crawl. Child Development, 69: 1299-1312
- Goldfield, E. (1989). Transition from rocking to crawling: Postural constraints on infant movement. Developmental Psychology, 25: 913-919.
- Berger, S., and Adolph, K. (2007). Learning and development in infant locomotion. Progress in Brain Research, 164: 237-255.
- Karasik, L., Tamis-LeMonda, C., Adolph, K. (2011). Transition from crawling to walking and infants’ actions with objects and people. Child Development, 82: 1199-1209.
- Karasik, L., Adolph, K., Tamis-LeMonda, C., and Zuckerman, A. (2012). Carry on: Spontaneous object carrying in 13-month-old crawling and walking infants. Developmental Psychology, 48: 389-397.
- Goodkin, J. (2001). Baby not crawling? Not to worry! Contemporary Pediatrics, 18: 14.
- Pitman, T. (2009). 0-1 year: Tummy time. Today’s Parent, 26: 129.
- Mondschein, E., Adolph, K., and Tamis-LeMonda, C. (2000). Gender bias in mothers’ expectations about infant crawling. Journal of Experimental Child Psychology, 77: 304-316.