Background

The prevalence of obesity in U.S. children and adolescents has skyrocketed in recent decades. While dietary changes may have contributed to this alarming trend, available evidence suggests that decreased physical activity is the major cause. This observation indicates that public health efforts to attack the burgeoning obesity rate in children should focus on promotion of physical activity. Unfortunately, the scientific literature provides relatively little guidance concerning effective interventions to promote physical activity in children. Many experts believe that physical activity levels of children have declined because of changes in the social and physical environment in which they grow up. These changes include increases in television watching, use of the Internet, and playing video games. Other potentially important factors are neighborhood safety, dependence on motorized transport, and families in which both parents work outside the home. The net effect of these societal changes has been to reduce the exposure of children to social and physical environments that encourage activity (and increase their exposure to environments that deter, limit, or discourage physical activity). Pre-school children spend most of their time at home and in supervised day-care settings. Hence, efforts to promote physical activity would have to be directed at the home and/or day-care settings. Regrettably, our current knowledge of the factors that affect physical activity of young children in home and day-care settings is quite limited. We know of no previous studies that have examined the determinants of physical activity in children in day-care centers.

Purpose

The purpose of the proposed investigation is to identify social and physical environmental factors that associate with physical activity in pre-school children in day-care settings. The long-term goal of this research is to identify intervention strategies that will effectively increase the physical activity levels of young children.

Design and Study Population

Subjects for this study were children 3-5 years of age and who attended day-care centers at least six hours per day, five days per week. Data were collected by directly observing the children while they are in the day-care setting and by using accelerometers to objectively measure their physical activity in that setting. In addition, data were collected via surveys to be completed by parents and day-care personnel. Approximately 300 children participated in the study with nearly equal distribution between males and females, Whites and African Americans, and each of three ages (3, 4, and 5 years). Children and their parents were recruited to participate in the study through 9 day-care centers that agreed to serve as data collection sites. These centers included public, church-based, and commercial day-care facilities located in Columbia, South Carolina. Parents of participating children provided informed consent in accordance with the procedures of the University of South Carolina Institutional Review Board.

Measurement

Each child wore a CSA accelerometer for the duration of his/her stay at the day-care center (at least six hours) on three separate days during a two-week period. On those same days the child was directly observed for at least six hours. Data provided by the accelerometers were reduced to determine minute-by-minute participation in light, moderate, vigorous, and very vigorous physical activity. Data collected by direct observation were used to create variables that measure key physical and social environmental factors. These included: indicators of physical setting (classroom, playground, cafeteria, etc.); social context (interactions with other children and adult supervisors); and type of activity (group instruction, individual instruction, watching television or videos, free play, organized play, etc.). Each physical location in each day-care center was "audited" for characteristics that might affect physical activity (gross size, physical activity space, presence of items such as televisions, play equipment, etc.). Parents completed questionnaires assessing their own physical activity participation as well as various hypothesized family-based psychosocial and environmental determinants of physical activity. Day-care center personnel completed structured interviews providing information on policies and practices that might impact the children's physical activity (e.g., daily schedule protocols, staff education/training, curriculum, etc.).

Project Details

Timeline: 2000 - 2004 
Funding Source: Gerber Foods / Novartis
Principal Investigator: Russell R. Pate

Publications

Sirard JR, Trost SG, Pfeiffer KA, Dowda M, Pate RR. Calibration and evaluation of an objective measure of physical activity in preschool children. Journal of physical activity and health. 2005 Jul;2(3):345-57. [pdf]

Pate RR, Pfeiffer KA, Trost SG, Ziegler P, Dowda M. Physical activity among children attending preschools. Pediatrics. 2004;114(5):1258-63.[pdf]

Dowda M, Pate RR, Trost SG, Almeida MJ, Sirard JR. Influences of preschool policies and practices on children's physical activity. Journal of Community Health. 2004;29(3):183-96.[pdf]

Trost SG, Sirard JR, Dowda M, Pfeiffer KA, Pate RR. Physical activity in overweight and nonoverweight preschool children. International Journal of Obesity. 2003;27(7):834-9.[pdf]