“My 6-month old daughter rocks on her belly and moves her arms all around. It looks like she is swimming on land! What is going on while she is playing like that?”
This swimming motion, common during the development of 5-6 month olds, is also known as pivot prone. The first time you might see something like this would be during a Landau reaction. The Landau reaction emerges at approximately 3 months as a reflex/postural reaction, allowing the baby to extend against gravity while held at the stomach. However, by 5-6 months of age, the baby has taken this foundation movement and has developed the strength and flexibility to play with it in a variety of ways while on the floor. These new sensations and movement keep interest in the activity.
What is happening during this motion?