Brian D. Clocksin

Quantifying physical activity in first-through fourth-grade physical education via pedometry.

The aim of this study was to determine pedometry steps per minute (SPM) cutscores that accurately quantify physical activity (PA) time in first-through fourth-grade physical education. A total of 257 participants were grouped in two data pools, first-and second-grade (n = 126), and third- and fourth-grade (n = 131). Systematic observation was the PA criterion instrument and pedometry was the predictor instrument. Correlations between physical activity measures were strong (r = 82–89, p < .01). Ten min of PA and 33.33% of the lesson time engaged in PA within a 30-min class can be quantified by 61–63 SPM for first- and second-grade, and 58–61 SPM for third- and fourth-grade. In conclusion: (a) SPM values were a valid indicator of students achieving or not achieving PA criteria, and (b) pedometry is a valid and practical tool for physical activity surveillance within physical education.

Tri-Axial Accelerometry and Heart Rate Telemetry: Relation and Agreement with Behavioral Observation in Elementary Physical Education

The relation and agreement of tri-axial accelerometry and heart rate telemetry in measuring moderate to vigorous physical activity were examined in association to behavioral observation during 1st- and 2nd-grade physical education. In Study 1, physical activity measures of heart rate and behavioral observation were collected on 346 participants ages 6-9 years (M = 7.27, SD = 0.58). In Study 2, participants (N = 125) were 6-9 (M = 6.98, SD = 0.72) years old and had their physical activity measured via tri-axial accelerometry and behavioral observation. Tri-axial accelerometry and observation (r = .77 to .79, p ≤ .01) demonstrated a stronger relation than heart rate and observation (r = .42 to .49, p ≤ .01). Bland-Altman plots (Bland & Altman, 1986) revealed a marginally better agreement between tri-axial accelerometry and observation than between heart rate and observation, but both accelerometry and heart rate telemetry significantly overestimated physical activity time. In conclusion, neither accelerometry nor heart rate, following the instrumentation data collection protocol in this study, would be an acceptable alternative for behavioral observation.

Understanding Youth Obesity and Media Use: Implications for Future Intervention Programs.

Nearly six years have passed since the Physical Activity and Health: A Report of the Surgeon General (USDHHS, 1996) described the health and fitnesa status of Amricas yarth. The Sugeon Guxds Call to Action to prevent and Decrease Overweight and Obesity (USDHHS, 2001) provides a camprehensive review of research on the epidemiology, health risks, and prevalence of obesity in all segments of the poplation. Increasinngly, children and adolescents are turning to sedentary kisure-time activities. Media use has been linked to decread physical activity levels, incearsed BMI, and increased high-enugy food intake. This review of litnature pravides a comprehensive examination of the influence media use has on youth adiposity, dietary habits. and physical activity. Current and future intervention programs to decrease sedentary behavior in children are also highlighted. Reducing media use (including television, videaape viewing, nonacademic computer use, and video game playing) in youth cau address leisure-time sedentary behaviors. Future intervention program, using run interdisciplinary appach, need to decrease leisure-time sedentary behaviors while promoting active lifestyles.