15 About This Module: Physical Development


Have you heard the statistic that more Americans are overweight or obese than ever before? Many people are familiar with this statistic because many of us struggle with weight issues. Worse than that, however, is the fact that a high number of today’s children will have shorter life expectancies than their parents. How is this possible, you ask, with all the medical advances available today?

Sadly, this generation of kids is also overweight in record numbers – due partially to high sugar, high fat diets and partially to less physical activity — and as a result of their unhealthy habits, their life expectancies are shorter than their parents’ generations’. Of course, this doesn’t apply to healthy, nutritionally-balanced, and physically active kids, but, unfortunately, fewer kids today fall into this “healthy” category. Have you ever wondered how you would be different if you had eaten differently and had more outside time as a child? This is but one of the major topics you will learn about in this module.

What about sleep? Sleep is for the weak, right? Actually, that’s a factually wrong and philosophically unhealthy statement for many reasons. First, if you want your brain to function – i.e., remember things, process information logically, and regulate your emotions effectively – then you have to let it sleep. This is true for adults, but it is especially true for children and infants. Because children’s and infants’ brains are developing and growing so rapidly, they need even more sleep so their brains can organize, grow, and make new neural connections. Children need significantly more sleep than adults for this very reason. Children at age 2–3 need between 10–12 hours of sleep, which usually equates to a 7:30–8:00pm bedtime. Understanding the need and purpose of sleep at different ages helps you be better prepared to meet children’s needs and address problems in their behavior. Sleep is a must for children and adults alike.

Have you ever had the experience of holding a newborn baby? If so, then you were witness to an amazing spectacle of human development. Every newborn baby has just experienced a momentous physical event: transitioning to our physical world. Being born would be the equivalent of you suddenly, in your adult form, being sucked into, let’s say, outer space and then – within mere hours – your body quickly adapting to the lack of air in space and “turning on” an ability to get oxygen from, let’s say, photosynthesis (absorbing and processing of the sun’s rays). You literally survive via a different biological process than you ever have before being sucked into outer space. Can you imagine that? It seems ludicrous. Yet, in some ways, that is what happens when a baby goes from being in its mother’s womb, encased in water and connected to her body’s nutrients, to living in air and eating its own nutrients.

Why this far-fetched example of being sucked into outer space? Well, for starters, it is helpful to put into perspective how truly momentous and taxing the transition from womb to birth is. In fact, it is only in recent history that we actually expect most babies to live through this transition. Just a century ago and stretching far back into human history, many babies died shortly after birth for fairly simple reasons. It is truly one of the most difficult human physical feats in the lifespan – both for the mother doing the birthing and the baby attempting to survive after birth.

It is for this last reason that we, as humans, have evolved such that we have reflexes and sensory abilities present immediately at birth that help us survive the first days, months, and years in life. Sucking, for example, is an inborn reflex that helps us survive the transition to consuming our own food. Can you imagine if humans were not biologically programmed to suck? It would be nearly impossible to feed a newborn without it having the ability to suck. There are numerous abilities newborn humans “turn on” at birth so they can be more likely to live through the transition from the womb to independent life.

As humans, we aren’t born fully able to walk or talk. Yet, our senses are quite keen at birth, equipping us to learn and take in the world at a very fast pace. Motor skills unfold gradually, and, unlike horses who are born walking, our gross and fine motor capabilities emerge slowly over the first few years of life. (1)

Learning Outcomes

1.  Students will be able to explain the important milestone encountered within the biological/physical, cognitive, and socioemotional domains from infancy throughout adolescence. (1)


Upon completion of this module, the student will be able to:

  • Discuss developmental changes in the body.
  • Describe how motor skills develop.
  • Outline the course of sensory development.
  • Explain ways to promote healthy development. (1)


Online Learning Unit


Icon for the Creative Commons Attribution 4.0 International License

Child and Adolescent Psychology Copyright © by Lumen Learning is licensed under a Creative Commons Attribution 4.0 International License, except where otherwise noted.

Share This Book