James. N. Roemmich

Choice promotes the experience of autonomy, which enhances intrinsic motivation. Providing a greater choice of traditional active toys may increase children's activity time. Mastery also increases intrinsic motivation and is designed into exergames, which may increase play time of a single exergame, reducing the need for choice to motivate activity compared to traditional active toys. Providing both choice and mastery could be most efficacious at increasing activity time. The energy expenditure (EE) of an active play session is dependent on the duration of play and the rate of EE during play. The rate of EE of exergames and the same game played in traditional fashion is not known. The purpose was to test the basic parameters of choice and mastery on children's physical activity time, activity intensity, and energy expenditure.

Obesity is correlated with a sedentary lifestyle, and the motivation to be active or sedentary is correlated with obesity. The present study tests the hypothesis that the motivation to be active or sedentary is correlated with weight change when children reduce their sedentary behavior.

Purpose:Stress-induced cardiovascular reactivity is associated with the pathogenesis of cardiovascular disease. This study tested whether a simulated active commute to school dampened cardiovascular reactivity to a cognitive stressor typical to what children might experience during school.Me

Two studies determined whether interval exercise reduces children's stress reactivity. For Experiment 1 children completed interval exercise (n=14) or watched TV (n=14) for 25 min. After 20 min rest children completed a speech task. Speech‐induced diastolic blood pressure (DBP) reactivity was dampened in the exercise group (p<.05). For Experiment 2 children (n=22) completed interval exercise‐speech and TV‐speech conditions on separate days. Physical activity was assessed by accelerometry and aerobic fitness estimated by submaximal exercise. DBP, systolic BP, and heart rate (HR) reactivity to the speech stressor were dampened (p<.05) after exercise compared to TV watching. Fitness was positively associated with HR reactivity. Interval exercise that mimics usual patterns of physically active play dampens cardiovascular reactivity to interpersonal stress.

The relationship between cardiovascular stress reactivity and carotid artery intima‐media thickness (IMT) has been established in adults, but not yet studied in children. Cardiovascular reactivity to an ad lib speech was measured in 20 boys and 20 girls age 11.0 ± 1.4 years. Measures included heart rate (HR), systolic (SBP) and diastolic (DBP) blood pressure reactivity, and mean common carotid artery IMT. Sequential regression analyses were used to establish the incremental increase in R² for the prediction of IMT due to cardiovascular reactivity independent of age, socioeconomic status, race, percentage body fat, and baseline BP or HR. SBP reactivity (β=0.002, , p<.05), but not DBP reactivity (p=.12) or HR reactivity (p=.82), independently predicted carotid artery IMT. This study provides initial evidence that SBP reactivity is associated with IMT and perhaps the early pathogenesis of cardiovascular disease in childhood.