Physical activity for children under 5 years of age

This is an English summary of the Danish report: Fysisk aktivitet for de mindste børn (0-4 år) 

'Physical activity for children under 5 years of age – knowledge about prevention and health benefits' presents the evidence on the association between physical activity, sedentary behaviour and health among children under 5 years of age. The report includes scientific literature from the Danish Health Authority (Sundhedsstyrelsen) and international systematic reviews conducted by research institutions and authorities from various countries: World Health Organization, USA, Canada, and Australia.

In the report the level of the evidence is described as strong, moderate, low, very low or insufficient. The indicated levels of evidence are based on the assessment made in the literature reviews that form the basis of the report. In these literature reviews, the level of evidence is based on an evaluation of the amount and quality of research in the area and whether there is consistency in the results of the studies. Strong evidence indicates great confidence in the observed relationship between physical activity and a given health outcome. In order to obtain strong evidence for an association, much research and several high-quality studies that point in the same direction is required. In the case of insufficient evidence, there is insufficient research to determine whether there is an association. Amongst other things, this may be because it has not yet been sufficiently investigated, which often characterizes new areas of research.

Physical activity, motor and sensory development

Physical activity in early childhood form the basis of how children coordinate and control their bodies in relation to exploring their surroundings. These motor skills are prerequisites for participation in play, movement, and physical activity. In early childhood and also later in life. In addition, the youngest children sense the world through movement, and it is a way to communicate and interact with other people as well as seek attachments and safety. It is well documented that physical activity habits starts to develop early in life and tracks throughout the life span. Physical activity habits early in life are this expected to affect health in childhood, adolescence and in adulthood.

Physical activity and health

• There is moderate certainty evidence that physical activity improves cognitive development in children.
• There is low certainty evidence that physical activity improves children’s psychosocial health, e.g., increased self-esteem, self-perception, and social skills.
• There is low certainty evidence that physical activity can contribute to motor skills development. For example, studies show that infants who are stimulated to be active find it easier to lift and turn their head in different positions for longer periods of time, and that children 3-4 years of age find it easier to catch, throw, run, and kick.
• There is low certainty of evidence that physical activity has a positive impact on 3-4- year-old children’s weight status, such as reduced risk of adiposity.
• There is insufficient evidence of the association between physical activity and cardiometabolic health and bone health of children. However, studies find physical activity to be related to lower levels of cholesterol, triglycerides, systolic blood pressure, and bone growth in 3-5-year-old children
• There is insufficient evidence to describe a dose-response relationship between physical activity and cognitive development, motor skills, and psychosocial health, respectively, in children under 5 years of age.

Sedentary behaviour and health

Research on sedentary behaviour and health consequences in the youngest children is still at an early stage. Sedentary time among children is primarily measured by parent-reported screen time (TV, iPads or tablets), sitting or lying down (e.g. in a high chair, pram or stroller) or sedentary time spent sitting and listening to stories.

• There is very low certainty of evidence on the association between sedentary time and cognitive development. Some studies show a negative impact on children’s cognitive development. However, some studies show that listening to stories from an adult or caregiver may have a beneficial effect on children’s cognitive development, but the level of evidence is insufficient.
• There is very low certainty of evidence of an association between sedentary and motor skills development
• There is very low certainty of evidence that sedentary time has a negative impact on children’s psychosocial health. There is insufficient evidence to describe a doseresponse relationship, but studies suggest a possible negative dose-response relationship when sedentary time is measured by TV-time and in particilar when the content is of violent or noneducational character.
• There is insufficient evidence to determine a dose-response relationship between sedentary behaviour and cognitive development and motor skills.

Knowledge gaps and future perspectives

Early childhood is a crucial period in life, both in terms of the establishment of physical activity habits and physical literacy as well as the cognitive, emotional, and psychosocial development. However, the evidence on physical activity and health among children under the age of 5 is still sparse. This is partly due to difficulties in estimating physical activity among the youngest children because their movement behavior is unstructured and spontaneous. More high-quality studies are needed to strengthen the evidence.

Most of the literature is based on children of preschool age (3-4 years), while there is not much knowledge about children under 2 years of age. Children’s developmental stage varies greatly by age. Therefore, future research should differentiate within the age group to gain more knowledge about the health benefits of physical activity among the in relation to individual age. It is also important to support knowledge and methods for parents to stimulate their children to be physically active.