Physical Development and Health in Middle Childhood

Learning Objectives

By the end of this section, you will be able to:

• Identify growth trends and milestones in middle childhood
• Describe advances in gross and fine motor development in middle childhood
• Describe nutritional, sleep, and other health needs in middle childhood

Arif is outside with his friends after school. They are playing baseball, but because there are only six of them today, they are coming up with creative ways to make the game work. Arif is having a great time because he knows that he has really improved over the last few months in hitting and catching. He has been practicing with his uncle regularly and feels much more relaxed and capable. A year ago, he would have gone straight home and skipped the neighborhood game, but he is now taller, stronger, and more confident in his skills.

As children move into middle childhood they still look like little kids, but by the end of middle childhood, many have had a growth spurt and begin to look like adolescents. In addition to changes in physical growth, children are experiencing changes in gross motor skills and are becoming more coordinated (Lima et al., 2017). These changes allow them to be more capable when engaged in physical activities such as climbing a tree, playing tag, or having a neighborhood game of baseball. Similarly, the continuing development of fine motor skills is important for improving skills such as writing. Changes in nutritional and sleep needs and health issues are other important aspects of physical development during middle childhood.

Physical Growth and Development

Although there are a lot of individual differences during middle childhood, physical growth continues to happen in some predictable ways. As children move into middle childhood, they have often lost the rounded bellies and full faces associated with early childhood, and have a leaner appearance. There are not many sex differences at this point. Boys and girls are similar in size and body shape, although girls are often slightly smaller than boys (Lazzara, 2020). Children now grow steadily, if more slowly than earlier in life, adding approximately 2 to 3 inches in height and adding about 5 to 7 pounds per year in weight until they reach puberty (Lazzara, 2020). Around age seven, children average 44 inches tall and 50 pounds, but by age eleven, girls average 52 inches tall and 82 pounds, and boys average 52 inches tall and 77 pounds. Towards the end of middle childhood, as girls enter puberty, which typically occurs a few years earlier than for boys, they tend to be larger than boys of the same age. However, once boys begin puberty, the height and weight gap generally disappears, and in most cases, boys will grow taller and weigh more than girls (Lazzara, 2020). Hereditary differences in things like potential height and the growth spurts that can occur during middle childhood, however, lead to wide variability in size.

Several factors may influence how quickly children grow, including genetics and environmental factors. Genes determine about 80 percent of adult height, while the other 20 percent is influenced by environmental factors (Perkins et al., 2016). A lack of protein in the diet and childhood disease are particularly important environmental influences on height (Bozzoli et al., 2009; Koletzko et al., 2014). Nutritional deficits can lead to stunted growth, which often persists and can get worse if malnourishment continues (Kitsao-Wekulo et al., 2013). Furthermore, stunted growth in school-aged children is often associated with other concerns, including behavior problems and cognitive deficits (Hoddinott et al., 2013). Other environmental factors include prenatal development resources (such as maternal nutrition), severe neglect (Nelson et al., 2019), and even the family’s socioeconomic status (SES) or the wealth of the country or region they live in (Fox & Heaton, 2012; Mumm et al., 2016). For example, children in wealthier countries, living in more urban areas, or from families with better economic and educational resources often are physically healthier and have better nutrition outcomes (Fox & Heaton, 2012; Mumm et al., 2016; Schell et al., 2009).

Toward the end of middle childhood, some children may have a growth spurt as they begin the process of puberty, the stage in which they sexually mature as they prepare to enter adolescence. Around ages six to eight, the groundwork for puberty is being set by greater production of hormones from the adrenal glands (Mendle et al., 2019). These hormones prepare the body for physical maturation. However, the onset of true puberty, including changes in physical characteristics like voice changes and increased body hair, does not occur until later, between eight and thirteen years of age for girls and between nine and fourteen years of age for boys (Farello et al., 2020). Puberty typically lasts between 2.5 and 4 years (Cheng et al., 2019). A variety of hereditary and environmental factors can influence the timing of puberty. (You will learn more about this in 9.1 Physical Growth and Development in Adolescence.)

Along with the body, the brain experiences a growth spurt early in middle childhood and reaches 95 percent of its adult size between seven and eight years of age (Thompson et al., 2020). Although there is very little change in the number of neurons from infancy to adulthood, the brain develops in very important ways during childhood. During this stage of development, new synaptic connections continue to form between areas of the brain that are responsible for sensory and motor skills, and myelination increases (Buyanova & Arsalidou, 2021). The continued development of myelin across early and middle childhood partially explains why children show increased efficiency in reaction times and information processing abilities (Chevalier et al., 2015; Scantlebury et al., 2013). As a result, children will be able to perform tasks that require faster reaction times such as catching a ball, playing a musical instrument, or finally winning family game night.

During childhood, the neural connections in the brain are being fine-tuned. Synapses that are regularly used are strengthened, while other synapses are pruned. Synaptic pruning is the elimination of unneeded synapses in the brain, which allows for more efficient functioning. The location of the most significant changes in brain development is the prefrontal cortex, the most forward portion of the frontal lobe (Kolk & Rakic, 2022). This area is responsible for tasks such as logic, planning, memory, and attention. As you have learned, various environmental experiences play a role in shaping brain development.

The human brain consists of left and right hemispheres, joined by a bundle of nerve fibers called the corpus callosum, which continues to mature during middle childhood. During childhood, children are increasingly able to coordinate functioning across the two hemispheres of their brain, a process called lateralization. This process is important for the development of skills that are lateralized, such as language. As the brains of children develop, their left hemisphere, which is responsible for language production and comprehension, and their right hemisphere, which is responsible for intonation and understanding emotional nuances in language, begin to work together more effectively. This integration can be observed when children start to use more advanced language structures, such as longer sentences and more sophisticated vocabulary. Moreover, children become more capable of expressing and comprehending nuanced emotions through language, indicating a greater coordination between linguistic and emotional processing across both hemispheres.

Gross and Fine Motor Skills

Children continue to make significant gains in both their gross and fine motor skills during middle childhood. Recall that gross motor skills use the larger muscles and consist of large bodily movements. The skills that develop during this time include balance, running, jumping, climbing, throwing, and catching (Table 7.1). Children are becoming faster, more coordinated, and stronger. Advancements in these skills allow them to get involved in organized sports, ride bikes, skate, or study dance or martial arts (Figure 7.2).

Figure 7.2 As children’s brains and bodies grow, they can better coordinate their movements and delight in exploring their world through improved motor skills and reaction time. Grasping something with one’s hands requires fine motor skills, while larger body movements are gross motor skills. Both are required for activities like (a) swinging across a set of playground rings or (b) jumping rope. (credit a: modification of work “Monkey bar twins” by Donnie Ray Jones/Flickr, CC BY 2.0; credit b: modification of work “More Jedi obstacle course” by Library and Information Services Metropolitan State University/Flickr, Public Domain)

Fine motor skills use the smaller muscles and consist of smaller-scale bodily movements such as those that rely on the fingers and hands. Fine motor skills are important for many daily living activities including feeding and dressing (Van der Linde et al., 2015), as well as for many activities used for learning in school settings. During middle childhood, children continue to refine fine motor skills such as writing, cutting, drawing, painting, tying shoelaces, and buttoning (Table 7.1). They can use all eating utensils and are able to gradually draw more detailed shapes or pictures. Handwriting improves dramatically as children become more proficient at writing smaller and neater letters. Fine motor skills also allow children to learn to play a musical instrument such as the piano or guitar. The development of fine motor skills is also important for other aspects of development. For example, children who have well-developed fine motor skills have more advanced mathematical and reading achievement (Cameron et al., 2012).

Typical Age of Appearance in Years	Common Gross Motor Milestones	Common Fine Motor Milestones
6–7	Skipping Balancing on one foot with eyes closed	Cutting with scissors
8–9	Jumping vertically 8–10 inches	Producing neater handwriting Writing smaller letters of uniform size
10–12	Jumping 3 feet (high jump)	Drawing detailed and complex images and shapes

The development of fine motor skills is impacted by the experiences that children have (Figure 7.3). For example, some studies have shown increased fine motor dexterity among children who play video games (Adams et al., 2012). Culture is also an important factor that influences the development of motor skills. For example, children from Hong Kong, who often have early exposure to and practice with writing utensils and chopsticks, have more advanced fine motor skills than children from the United States (Chui et al., 2007). Differences by culture or gender are often due to differences in childrearing practices and in the timing and amount of exposure to certain skills that children receive.

Figure 7.3 Fine motor skills such as (a) writing, (b) tying one’s shoes, and (c) playing an instrument continue to develop throughout middle childhood. (credit a: modification of work “Child Writing” by Alyssa Sieb/nappy, Public Domain; credit b: modification of work “Tie Your Shoes, We’re Going Home” by William Klos/Flickr, CC BY 2.0; credit c: modification of work “Southern California Division – Jr. Music Camp 2012” by John Docter, Salvation Army USA West/Flickr, CC BY 2.0)

Health Needs in Middle Childhood

Children also have important health needs during middle childhood that are required to support their ability to develop in other areas, including cognition and socioemotional development. Sufficient sleep, adequate nutrition, and regular exercise are all important. Additionally, regular health and dental care, and attention to accident prevention and other health issues help to promote healthy development during this period.

Sleep

Sleep patterns play an important role in development during childhood. According to the American Academy of Sleep Medicine, children from six to twelve years of age should get nine to twelve hours of sleep every night (Paruthi et al., 2016) (Figure 7.4). One reason is that during sleep, the brain consolidates the information the child was exposed to during the day (Paller et al., 2021). In addition, it is during sleep that the release of human growth hormone occurs (Zaffanello et al., 2024). Human growth hormone is responsible for physical growth and muscle development. Lack of sleep can also affect children’s ability to focus, and is associated with crankiness, behavior problems, and difficulties in school (Liu et al., 2024).

Figure 7.4 Although children may no longer need a nap and will generally sleep less than they did during early childhood, quality sleep is still critical for physical, cognitive and socioemotional development. (credit: “Photo by thewaxaddict on Instagram: “#latergram #rw24 nap-time thanks to @julesbayview for the photo credit” by “kisluvkis”/Flickr, Public Domain)

Occasional disruptions in sleep are normal and may be the result of stressful situations at school or at home. Fortunately, such temporary sleep problems usually resolve on their own and do not create any long-term issues. However, if problems with sleep become more persistent, children have an increased risk of both emotional and behavioral difficulties, as well as ongoing problems with school performance (Williamson et al., 2020). Therefore, if a child is experiencing ongoing sleep problems that get worse over time, like night terrors, a physician should be consulted.

Healthy sleep habits and routines continue to be beneficial throughout childhood. For example, quiet reading time and avoiding electronics before bed helps encourage adequate, good quality sleep.

Nutrition

A healthful diet during middle childhood is important for physical, cognitive, and socioemotional development. Children need between 1,800 to 2,200 calories a day (Faizan & Rouster, 2023), which should be comprised of a range of minimally processed foods, including a variety of fruits and vegetables, whole grains, and protein, as well as small amounts of healthful oils, to grow and develop well (U.S. Department of Health and Human Services, 2015). However, processed foods with too much sugar, fat, and sodium are common, because they are less expensive, more accessible, and easier to prepare (Figure 7.5). As a result, many children have a diet full of sugary products, high-fat fast foods, and high levels of sodium, with both short- and long-term consequences. In the short term, poor nutrition is related to excess weight gain and constipation. Over the long term, possible consequences include obesity and the risk of cardiovascular disease, diabetes, hypertension, and other health and emotional problems (Saavedra & Prentice, 2023).

Figure 7.5 Although there have been significant improvements in healthful choices available to children for school lunches, less healthful options continue to be available. These include highly-processed foods like pre-made sandwiches or chocolate milk. (credit: modification of “Supporting the Healthy Growth of Our Children During National School Lunch Week” by Tim Lauer, principal of Meriwether Lewis Elementary School in Portland, Oregon/USDA.gov, Public Domain)

Obesity is a serious health concern. Nearly 19 percent of U.S. school-aged children have obesity, a percentage that has nearly doubled over the last several decades (Hales et al., 2018). Another 16 percent of children are overweight according to the Centers for Disease Control and Prevention (Stierman et al., 2021), as measured by body mass index (BMI). Children with a BMI in the ninety-fifth percentile or higher are considered obese. Children with a BMI between the eighty-fifth and ninety-fifth percentile for age are classified as being overweight. Obesity in children is associated with numerous health concerns, including high blood pressure and reductions in insulin, which has implications for depression and diabetes, as well as for other difficulties such as in mental health and academic achievement (Sahoo et al., 2015). Excess weight has also been shown to impair brain functioning, which in turn can harm memory and decision-making abilities (Liang et al., 2014).

Another possible consequence of poor nutrition is undernutrition, which occurs when children are not capable of absorbing adequate nutrients from their diet due to digestive medical issues or because they do not receive adequate nutrients. Wasting and stunting are two extreme forms of undernutrition that, while often a concern primarily in early childhood, may continue to occur during middle childhood, particularly in cases involving food insecurity, poverty, or chronic illness. Wasting is the tendency for children to be too thin for their height, while stunting occurs when they are too short for their age. These two forms of malnutrition are closely related and are often found in the same population of children (Thurstans et al., 2022). Undernutrition can increase risks of illness, poorer cognitive functioning, and poor mental and behavioral health (Kirolos et al., 2022).

Given that poor nutrition during childhood is linked to so many poor developmental outcomes, nutritional interventions that increase the overall quality of nutrition for children have been shown to increase academic performance and cognitive development (O’Brien et al., 2021). These interventions include programs to provide higher quality school lunches, as well as social programs to provide access to high quality food for lower income families. Children have a high likelihood of being resilient from early nutrition risks when prevention and intervention programs are made available in early and middle childhood (Suryawan et al., 2022). There are social programs that educate parents, provide free lunches, and provide access to affordable, healthful food.

Exercise

Physical activity and engagement in sports during middle childhood have a positive impact on the motor, cardiovascular, hormonal, respiratory, immunologic, and nervous systems of school-aged children, and are associated with better cognitive and emotional development (Bidzan-Bluma & Lipowski, 2018). As a result, the CDC recommends that school-aged children get at least one hour of moderate to vigorous physical activity per day. This physical activity can occur in school during physical education classes or recess, during unstructured play outside of school, or through involvement in organized sports teams.

Despite the benefits, children are more sedentary now than they have been in past decades, and only about a third regularly engage in physical activity (Graf, 2016). This inactivity is a global issue. According to the World Health Organization, 85 percent of children across the world are considered inactive, although rates do vary slightly by country (Guthold et al., 2020). For example, one study reported that only 26.2 percent of children in Thailand met the guidelines for adequate physical activity (Katewongsa et al., 2021), while 33 percent of children in Canada (Barnes et al., 2018), and 60 percent of children in Shanghai, China (Xiang et al., 2020) met the guidelines for physical activity before the COVID-19 pandemic. However, the rates dropped to approximately 18 percent for both countries during the pandemic.

Recent research has highlighted barriers that make it difficult for children to get the recommended amount of daily exercise. For example, children who live in areas with high levels of poverty are less likely to have access to high-quality recreational facilities and safe places to play (Kim & Cubbin, 2020). This can result in decreased physical activity levels among children. In some countries in the Middle East and northern Africa, barriers to physical activity include the absence of social support from parents and friends, lack of appropriate facilities, and hot climate (Chaabane et al., 2021).¹ In many countries around the world, girls also have additional barriers to participating in physical activity related to cultural roles for females that includes greater encouragement for boys to engage in sporting activities (Kretschmer et al., 2023). Promoting physical activity and health for the entire family through school-based interventions shows promising evidence of reducing sedentary behavior and improving healthy behaviors (Santos et al., 2023).

Link to Learning

Designed for parents with children ages 6–12, this video about physical activity for children discusses the importance of regular physical activity, how much physical activity children need, and how to get children moving.

Accident Prevention

As discussed in 5.1 Physical Health and Growth in Early Childhood, unintentional injuries are a leading cause of both death and disabilities among children (West et al., 2021). This continues to be true in middle childhood. The leading causes of nonfatal child injuries in the United States are automobile accidents, drowning, poisoning, fires, and suffocation. Globally, road traffic injuries, drownings, fire, and poisoning are the most common causes of unintentional injuries among children (Chandran et al., 2010).

Injuries in children are often preventable. In fact, prevention strategies have successfully reduced injury-related deaths in higher-income countries such as the United States (CDC, 2019). Some of the more effective prevention strategies include the required use of seat belts, laws regarding distracted driving, the use of bicycle helmets, and the use of crossing guards near schools to reduce deaths and injuries related to automobile accidents. To reduce drownings, caregivers are encouraged to give children swimming lessons, to use life jackets, and to closely supervise children near water. The use of safety caps on medicine bottles and the practice of keeping medications out of the sight and reach of children are helpful strategies for reducing accidental poisonings and overdoses. Although these prevention strategies have been effective in higher-income countries, unintentional injuries continue to disproportionately harm children in low- and middle-income countries (Tupetz et al., 2020).

Although unintentional injuries have been decreasing in recent years, firearm deaths have been steadily increasing; a 40.5 percent increase occurred from 2018 to 2021 (Goldstick et al., 2022). In 2020, the leading cause of death among children in the United States was due to firearms (Goldstick et al., 2022), passing motor vehicle accidents for the first time.

Fortunately, most unintentional injuries and deaths are preventable, and in fact, ongoing and systematic prevention efforts that focus on modifying behaviors and environmental factors can effectively reduce the rates of unintentional injuries (Jullien, 2021). However, interventions need to attend to changing policies and trends in health risks. For example, the state of Georgia saw an increase in pediatric firearm injuries following state law changes that reduced restrictions on carrying firearms and during the COVID-19 pandemic indicating a greater need for effective prevention strategies, such as providing greater education on violence prevention and safe storage of firearms (Mulugeta et al., 2024; Lee et al., 2022).

Health and Dental Care

Most children between the ages of six and eleven in the United States are reported to be in either excellent or very good physical health (Parasuraman et al., 2020). Middle childhood is also the ideal time for children to develop healthy habits that can persist into adulthood as they begin to develop independence in self-care. As a result, it is important for children to continue to receive regular health care. In fact, primary health care is both effective and cost-effective for enhancing both physical and mental health (Kraef et al., 2020). Unfortunately, almost 4.5 million U.S. children do not have health insurance; they are less likely to receive needed health care and, as a result, may have poorer overall health (AAP, 2020). While global mortality rates among children over the age of five have dropped by more than 50 percent (UNICEF, 2019), children across the world continue to have unmet health needs due to limited access to health care (Cheng & Shilkofski, 2019).

Dental care is also very important in this stage of life. Beginning around age six, children begin to lose their deciduous teeth, often referred to as baby teeth (Figure 7.6). The first tooth lost is usually in the center of the mouth, which is why you may be able to picture six- or seven-year-old children with a gap in their smile. While they are losing their deciduous teeth, a process that continues until about age twelve, children are simultaneously gaining permanent teeth.

Figure 7.6 Losing baby teeth is a normal process during early childhood. Children usually lose their front teeth around the age of six, although it can happen as early as age four or as late as age eight. (credit: modification of work “tooth fairy fodder” by Thomas Kriese/Flickr, CC BY 2.0)

Severe tooth decay can harm a child’s development, including socioemotional development (Ramos-Jorge et al., 2014) and increased school absenteeism (Krisdapong et al., 2013). For example, studies with children in several low- to middle-income countries such as Thailand have found that tooth decay has a negative impact on children’s social interactions as well as their self-esteem. Children in middle childhood are at risk of developing tooth decay and cavities due to factors such as poor oral hygiene, sugary diets, and irregular dental visits. Good oral care, including regular visits to the dentist and daily brushing and flossing, is important to maintain healthy teeth and to avoid tooth decay.

Other Health Issues

Although middle childhood is generally a healthy period for many children, there are some common health issues that are often seen during middle childhood, such as asthma and diabetes.

Asthma is a life-long, chronic lung disease that causes inflammation in the airways, making it difficult to breathe. Asthma is a serious public health problem globally (WHO, 2024). It affects about 8 percent of children in the United States (Federal Interagency Forum on Child and Family Statistics, 2017). Although there is no known single cause of asthma, a child is more likely to have asthma if other family members have asthma, if they have other allergic conditions, if they live in urban areas or areas with high air pollution, and if they have obesity (WHO, 2024). Avoiding common triggers of asthma, including air pollution and allergies, can reduce the symptoms of asthma such as shortness of breath and tightness in the chest (McCarthy, 2022). Although it can typically be medically managed, uncontrolled asthma is one of the leading causes of school absences among children and can also interfere with sleep and physical activity (Qin et al., 2022).

Diabetes, a metabolic disorder, is another chronic health issue that can have significant effects on child development. Until recently, most cases in children were type 1 diabetes, a disease in which the immune system attacks healthy tissue and results in the body not producing enough insulin to get glucose or sugar into the cells. However, type 2 diabetes, which used to be considered “adult-onset diabetes,” is increasing among children and is often preventable. Risk factors for type 2 diabetes include excess weight, inactivity, and having a family history which leads to increase insulin resistance (CDC, 2022). Although both types of diabetes can be managed, diabetes and other chronic illnesses in childhood have been linked to increased behavior problems and socioemotional concerns in children (Lupini et al., 2023). Many of the behavioral and socioemotional risks for children with chronic illnesses such as diabetes may be prevented through careful monitoring and treatment of symptoms.

Many of the health issues that children may face in middle childhood are experienced at a higher rate for children from a lower SES and for children from historically marginalized races or ethnicities. For example, childhood obesity, diabetes, and poor nutrition are more common risks for those in lower income countries and minority racial/ethnic groups in wealthier countries (Alkhatib & Obita, 2024). Often these trends are related to complex socioeconomic risk factors that may occur at a higher rate, particularly in families, neighborhoods, and regions facing socioeconomic inequality. For instance, families with a lower SES often have less access to more healthful foods, such as fresh produce and easier access to less healthy fast-food (Chatham & Mixer, 2019). In addition, healthier foods, such as fresh fruit and vegetables often cost more than less healthy food options (Chatham & Mixer, 2019). Further, income and education have been found to be associated with quality of diet and levels of physical activity, both of which are closely associated with being overweight or obese (Reis et al. 2020). Prevention and intervention efforts that focus on promoting a healthy lifestyle in combination with programs that support those most at risk of poor nutrition are effective strategies to promote public health (Obita & Alkhatib, 2023).

There are also socioeconomic disparities in risks of accidents, injuries, and asthma. For example, in the United States firearm injuries and deaths are a higher risk in states with higher poverty and disproportionately impact Black children (Roberts et al., 2023). As mentioned earlier, prevention strategies and community policies show promise in reducing these risks. Finally, risks of childhood asthma affects some racial and ethnic populations more than others with non-Latinx Black children having the higher rates (10.6 percent) followed by non-Latinx White (7.7 percent), Asians (3.8 percent) and Latinx children (6.6 percent). These disparities are likely influenced by SES, environmental exposures to pollutants, exposure to long-term stress, and access to quality health care (Grant et al., 2022).² Health-care providers can use this information to screen children living in neighborhoods that face higher risks, such as those experiencing greater exposure to air pollution. Local governments and community organizations can also work to improve neighborhood conditions in these areas (Aris et al., 2023).