How lifting the head prepares infants for sitting, crawling, and standing
In this lesson we learn to be comfortable on the belly while orienting the head and eyes to the horizon.
Infants spend the first 9 months of their lives curled up in the uterus, and have to develop the forward lumbar curve of the low back through action. On the belly they lift the head to see and engage with their environment, and as they do they develop the powerful extensor muscles of the back. The pull of the thick muscles along the lower back creates the forward curve of the lumbar spine, and these changes prepare them to bear weight clearly through the spine when they begin to sit and stand.
As you can see in this video, lifting the head in the center is only the beginning of the process.
Turning to look, Adia shifts her weight from one elbow to another, her spine and rib cage bend as she rolls her pelvis to the side and draws up one knee along the floor. As she shifts her weight over the elbows and draws up one knee, she learns skills that will later allow her to shift weight on hands and knees, leading to a more advanced (unstable) and efficient (less friction) crawling pattern on hands and knees.