When considering what it means to move ideally, the observation of the developing infant provides essential information.
All children, no matter where they are born on this planet, undergo CNS maturation in the first 13 months of life.
Unlike many other mammal species, when humans are born they are more or less useless from a central nervous system perspective, and unable to even carry out small purposeful movements.
As the brain and the rest of the Central Nervous System (CNS) mature, the baby develops accordingly and starts to adopt new postures and movement patterns.
These movements are largely informed by, and organised around, the needs of the child, and the surrounding environment. Emotional motivation is thus an important component in stimulating the installation of postural development “software.” Ie: The infant starts to lift their head and legs to adjust the entire posture to be able to look around for the parent.
As the CNS matures the needs of the infant continues to change.
The first 4.5 months are spent developing good sagittal stabilization and only after that has been achieved can babies assume positions where they can lift their legs, reach across the midline, start the turning process, and for example take one arm out of its support function to reach for a toy or other interesting objects.
After basic stabilization of the core in the sagittal plane is completed, the locomotor function of extremities occurs. From 4.5 months, the infant starts to reach across the midline when supine. Motivation, once again, triggers trunk rotation at the age of 5 months when the infant can turn to a sidelying position and complete rolling from supine to prone at 6 months of age.
In the prone position, the contralateral pattern of locomotor function develops. If the left arm serves as a support, the infant simultaneously weightbears on the right knee, with the right arm reaching and the left leg stepping forward. The kinetic chain principles are the same as described for the ipsilateral pattern. Stepping forward and supporting functions are reciprocal; they are the same movements, only in opposite directions.
Proper interaction with the environment influences the infant’s complex behavioral repertoire. In this regard, the adult structure, as well as the function of the individual, are dependent on a wide range of developmental inputs derived from their local environment, both physical and emotional.
Because the bones of an infant are relatively soft, the postural positions, along with the effects of gravity and the muscles actively pulling on the bones are important in developing good shapes of bones, joints, and muscular pull
The patterns residing in the CNS, whos installation is stimulated from environmental inputs, are innate, and thus can be considered our true template for movement stability.
Primitive reflexes organized on spinal and brain stem levels do not “disappear” after the neonatal stage. These motor patterns are simply inhibited by higher levels of control as the CNS matures. They become integrated within more complex patterns controlled at the subcortical and cortical levels.