Some principles regarding physical growth can help understand a child’s physical development. The growth of a child’s body follows a directional pattern in three ways. Knowing this is important so expectations of a child’s physical abilities are appropriate. The patterns of development are:
Large to small muscle or gross to fine motor development
Large- to small-muscle development means large muscles develop in the neck, trunk, arms, and legs before the small muscles in the fingers, hands, wrists, and eyes develop. Children can walk before they can write or scribble.
Head to toe or top to bottom
A second pattern is children’s muscles develop from head to toe called cephalocaudal law. This is why babies can hold up their heads long before they can walk.
Inside to outside or center to outside
A third pattern is muscles develop from the center of the body first and then toward the outside of the body called proximodistal law. Muscles around the trunk of the body develop earlier and are stronger than muscles in the hands, feet, etc.
General to Specific Growth Growth
The large-muscle movement begins with waving of the arms and legs of infants and then develops into the more specific movements of an older child who can walk and draw a picture. So, muscle growth begins with more general abilities and becomes more specific and defined as children get older.
Differentiation and Integration in Growth
Differentiation is the process that a child’s muscles go through as he or she gains control over specific parts of the body and head. Once children have found (differentiated) the parts of their body, they can integrate the movements and combine specific movements to perform more complex physical activities, such as walking, building a block tower, or riding a bike.
Variations in Growth
Children vary in their physical abilities at different ages. Different parts of the body grow at different rates. The range of physical skills to be expected in gross-or fine-motor development will be very different for infants versus preschoolers.
Optimal Tendency in Growth
In children, growth generally tries to fulfill its potential. If growth is slowed for a particular reason, such as malnutrition, the body will try to catch up when it can do so. This is one reason why children may develop skills in later years even if delays occurred at an earlier point in their development.
Different areas of a child’s body will grow at different times. In other words, development is orderly and occurs in a pattern. Children must be able to stand before they can walk. This pattern is evident in several ways, such as rolling over before sitting up, sitting up before crawling and crawling before walking, etc.
Growth during Critical Periods
Growth in certain areas of a child’s physical development may be more important at particular times during childhood. For example, recent brain research indicates the first few years of life are very important in the development of the brain’s growth and for intellectual competence. Similarly, the critical time for the development of motor skills is between 18 and 60 months of age (1 to 5 years). Research suggests that children go through four physical growth cycles: two of slow growth and two of rapid growth. The first period of rapid physical growth goes from conception to the age of 6 months. The rate of growth gradually slows during the toddler and preschool periods. The second period of rapid growth is during puberty in the years of preadolescence and adolescence. Another period of leveling off occurs after puberty until adult growth is achieved.