Play is the business of preschoolers. In order for them to become competent in playing and interacting with their environment, they must go through significant changes in their bodies and physical abilities. Preschooler bodies tend to be more proportioned and look more adult-like versus baby-like. They will be able to move their bodies in more sophisticated ways and we see a marked improvement in the balance and coordination.

Let’s take a look at what’s happening in a preschooler’s physical development by examining the growing body.

7.12.1 The Growing Body

Children’s bodies are continuing to develop throughout the preschool years but we may see things slow down a bit compared to the rate of growth during infancy and toddlerhood. One thing immediately noticeable is that children start the preschool years with all 20 of their teeth! Children will experience widening of the mouth and jaw to make room for permanent teeth (AAP, 2012). This will make a preschooler’s facial features more distinct and appear more mature.

A 3 year old preschooler will still present with a large head as compared to the rest of their body, looking more like a toddler than a preschooler. Their bodies eventually become more proportioned. Preschoolers start to lose the endearing “baby fat” and start to gain more muscle (AAP, 2012). The typical growth for three to six year olds includes gains of 4-5 pounds per year, 2-3 inches in length per year, and 20/20 (or perfect vision) capabilities by 4 years old (MedlinePlus, 2023).

By now, most preschoolers have achieved control of their bladder and bowel muscles and are potty trained. It is common for preschoolers to have accidents, especially at night, as children practice staying dry for long periods of time. The American Academy of Pediatrics states that there are three common reasons why children will have accidents at night, listed below (AAP, 2021):

Communication between the brain and bladder: If the bladder signals the brain that it’s filling up with urine—and the brain doesn’t send a message back to the bladder to relax and hold the urine until morning—bedwetting will happen. Likewise, if the bladder signals the brain that it’s filling up with urine and the brain doesn’t hear the signals, especially during deep sleep, bedwetting will happen.

Stress or trauma: Some​times when children experience stress or traumatic events, or when they get sick or constipated, children who have previously been dry at night can have bouts of bedwetting. This is a different problem than the child who has never been dry at night. Children with these short-term episodes of bedwetting usually have dry nights when the underlying problem resolves.

Medical concerns. Rarely, some children begin to wet the bed as a result of a serious medical problem.

Preschoolers require adequate amounts of sleep to recharge their bodies each day. The CDC recommends that children ages 3-5 get 10–13 hours per 24 hours, including naps (CDC, 2022). When children get the proper amount of sleep, they are more alert, have improved cognitive functions, and are able to regulate themselves (Pacheco, 2023). Preschoolers also require a healthy and balanced diet that includes fruits and vegetables which provide young bodies with vitamins and minerals to support growth and immune function. Children who do not get adequate nutrition may experience growth delays. Lack of nutrition and sleep can lead to long term consequences if not addressed early.