Program

Oct 18, 2012

OVERVIEW

The American Heart Association (AHA) Physical Activity Intervention is a school-based program designed to reduce risk factors of cardiovascular disease in children.  The program has healthy living education and physical activity components.  In an experimental evaluation of the program, 18 schools were randomly assigned to have their students participate in one of the following three study groups: 1) the AHA Physical Activity Intervention, 2) the AHA Physical Activity Intervention for at-risk children, or 3) physical education as usual control group.  Results indicated that children in intervention groups experienced better results relative to controls on a variety of outcomes, including cholesterol, diastolic blood pressure, and skinfold thickness.  However, there were also no impacts on a number of other important health outcomes, including BMI, physical activity, and diet.

DESCRIPTION OF PROGRAM

Target population:  Elementary school children.

The AHA Physical Activity Intervention is a universal intervention designed to reduce cardiovascular disease risk factors in children regardless of their current health status.  The program is implemented in elementary schools by classroom teachers and includes a healthy living curriculum and an aerobic exercise component.

The healthy living education component is implemented twice a week over an eight-week period.  The program curriculum includes information on selecting heart-healthy foods, the importance of getting regular exercise, the risks associated with smoking, and ways to resist peer pressure to smoke.

The physical activity component is implemented three times a week over the eight-week intervention period.  The sessions have an aerobic exercise focus and include activities such as jumping rope, relay races, parachute games, and aerobic dance.

Schools assigned to the AHA Physical Activity Intervention have regular classroom teachers provide instruction to all 3rd and 4th grade students based on the AHA Lower and Upper Elementary School Site Program Kit twice a week for a total of 8 weeks.

EVALUATION (S) OF PROGRAM

Harrell, J.S., Gansky, S.A., McMurray, R.G., Bangdiwala, S.I., Frauman, A., & Bradley, C.B.  (1998). School-based interventions improve heart health in children with multiple cardiovascular disease risk factors.  Pediatrics, 102, 371-380.

Evaluated population:  A total of 2,207 third- and fourth-grade children attending 18 elementary schools in the state of North Carolina completed the evaluation.  This study reports on the 422 children who met the criteria for the risk-based intervention as outlined below (including those who were at risk, but assigned to the other conditions). Half of the schools in the sample were located in urban areas, and half were located in rural areas.

Approach:   Schools were randomly selected to have their children participate in the study.  Three school clusters were randomly selected within six region and urban/rural strata.  The 18 schools were then randomly assigned to 1) the AHA Physical Activity Intervention, 2) the AHA Physical Activity Intervention for at-risk children, or 3) a no-treatment control group.

Children assigned to the risk-based intervention group were eligible to participate in the program if they possessed low aerobic power (physical activity) and one of the following two risk factors for cardiovascular disease:  high cholesterol or obesity. Students with high cholesterol received nutrition classes in groups of 5 to 8 students twice a week for 8 weeks from a registered nurse. Students who were obese received physical activity classes similar to those given to students in the universal intervention group, but in groups of 5 to 8 students instead of an entire classroom. These students received instruction three times a week for 8 weeks from physical educators.

Children in schools assigned to the no-treatment control group attended their regular health and physical education classes.

Children were assessed at baseline and within two weeks of the intervention’s conclusion.  Participants were measured for cholesterol, blood pressure, skinfold thickness, BMI, exercising heart rate, physical activity, diet, and exercise and nutrition knowledge.

Baseline analyses revealed significant differences of physiological factors across interventions, race, and age. Thus, posttest analyses adjusted for race and age. Analyses at the student level did not account for the nesting of students in classrooms or schools. This is a limitation of the study.

Results:  Two sets of analyses were conducted – one at the student level and one at the school level. Results for each set of analyses are presented below.

Cholesterol.  At the individual level, children in the risk-based intervention group and in the universal intervention group experienced significantly greater decreases in cholesterol relative to children in the control group.  School level analyses found no significant differences across groups on this outcome, however.

Blood pressure.  School level analyses found that participants in the universal intervention group experienced significantly lower increases in systolic blood pressure relative to control participants.  There were no differences between controls and individuals in the risk-based intervention.  At the individual level, the risk-based intervention group experienced a significantly lower increase in systolic blood pressure relative to controls.  However, there were no significant differences between universal intervention participants and controls.  For diastolic blood pressure, there were no significant differences in change across the intervention groups at the school or individual levels.

Skinfold thickness.  At the school level, there were no significant differences across study groups in changes in skinfold thickness.  At the individual level, children in both the risk-based and universal intervention groups experienced a significantly greater decrease in skinfold thickness relative to controls.

BMI.  There were no significant changes across groups on BMI at the school or individual level analyses.

Exercising heart rate.  At the school level, there were no differences across groups on measures of exercising heart rate.  However, at the individual level, participants in the universal intervention group had significantly greater improvements in exercising heart rate relative to control participants.

Physical activity.  There were no differences across groups on improvements in physical activity at the school or individual level analyses.

Diet.  There were no differences across groups on improvements in fat intake at the school or individual level analyses.

Exercise and nutrition knowledge.  School and individual level analyses showed that participants in both intervention groups had significantly more nutrition knowledge than controls.  School level and individual level analyses found that individuals in the universal invention had more exercise knowledge than individuals in the control group.  Additionally, at the school level, individuals in the universal intervention group had more overall health knowledge than individuals in the control group.  Finally, at the individual level, participants in both intervention groups had better overall health knowledge than controls.

Overall, results indicate that children in the intervention groups experienced better results relative to children in the control group on cholesterol, diastolic blood pressure, and skinfold thickness, but on BMI, physical activity, or diet. Children assigned to the universal program had a better exercising hear rate than controls, whereas children in the risk-based programs had lower increases in systolic blood pressure.

SOURCES FOR MORE INFORMATION

References:

Harrell, J.S., Gansky, S.A., McMurray, R.G., Bangdiwala, S.I., Frauman, A., & Bradley, C.B.  (1998). School-based interventions improve heart health in children with multiple cardiovascular disease risk factors.  Pediatrics, 102, 371-380.

Keywords:  Children, Elementary, Co-ed, School-based, Skills Training, Nutrition, Urban, Rural and/or Small Towns, Obesity.

Program information last updated on 10/18/12.