Physical activity participation in preschool age children born very preterm

Abstract

Participation in physical activity (PA) is associated with wide ranging health benefits at preschool age and across the lifespan, including favourable cardiometabolic and psychosocial outcomes. Many typically developing preschool age children are not meeting 24-hour movement guidelines in Australia and internationally. Children born very preterm (VP; <32 weeks’ gestation) may be at higher risk of physical inactivity due to myriad comorbidities associated with preterm birth, including adverse respiratory, neurological and motor outcomes. However, studies investigating PA participation in preschool age VP and term-born (born >=37 weeks’ gestation) children are sparse. This thesis used the International Classification of Functioning, Disability and Health children and youth version (ICF-CY) framework to compare PA participation and motor outcomes of children born VP with term-born children at preschool age over four studies.

Study one was a systematic review and meta-analysis investigating motor outcomes of 3- to 6-year-old VP and term-born children within the ICF-CY framework. Children born VP had poorer outcomes than their term-born peers within the body structure and function and activity domains. However, no data on participation domain outcomes were identified.

The second study examined the agreement between parent-reported and accelerometer-measured 24-hour movement behaviour in 4- to 5-year-old children. Agreement between the two measures of sleep was moderate, but poor for PA and stationary duration. Parents under-reported PA and stationary behaviour relative to the accelerometer, and VP birth, higher social risk and male sex were associated with the difference between the two measures.

Study three compared motor outcomes within the ICF-CY body structure and function, activity and participation domains by examining grip strength, motor competence (MC) and PA participation in 98 VP and 84 term-born 4- to 5-year-old children. Children born VP had poorer preferred and non-preferred grip strength than term-born children, but there was little difference in bimanual grip strength between the groups. Motor competence was poorer for children born VP than term-born children as measured by the Movement Assessment Battery for Children, second edition and the Little Developmental Coordination Disorder Questionnaire. Using accelerometer data, children born VP completed less PA and more stationary time, and VP parents reported less unstructured PA and more minutes of screen time per day than parents of term-born children. Although adherence to the Australian 24-hour Movement Guidelines was poor for both groups, a lower proportion of VP children met the PA and screen time recommendations than their term-born peers.

Study four examined the relationships between ICF-CY domains by investigating associations between grip strength, MC and PA levels at 4 to 5 years of age, determining if associations differed between VP and term-born children. Irrespective of birth group, more PA and less stationary behaviour were associated with better MC, and better MC was associated with greater grip strength. For children born VP, more PA was associated with better balance skills, and better balance skills were associated with greater grip strength. Physical activity levels did not appear to be associated with grip strength in 4- to 5-year-old children.

Overall this thesis demonstrates that preschool age children born VP experience poorer motor outcomes than term-born children within all ICF-CY domains. The studies within this thesis form the foundation for future research of PA participation in VP preschool age children, and contribute to a deeper understanding of the PA participation trajectory in this population. These findings have substantial implications for allied health clinicians involved in the management and developmental follow-up of children born VP, as well as for early educators and the design of PA promotion strategies.