Michelle Ihmels, Gregory J. Welk, James J. McClain and Jodee Schaben
Advances in BIA offer practical alternative approaches to assessing body composition in young adolescents and have not been studied for comparability.
This study compared reliability and convergent validity of three field tests (2-site skinfold, Omron and Tanita BIA devices) on young adolescents. Reliability was determined using intraclass correlation coefficients, convergent validity was examined by computing correlations among the three estimates, differences in estimated body fat values were evaluated using repeated-measures ANOVA, and classification agreement was computed for achieving FITNESSGRAM® Healthy Fitness Zone.
ICC values of all three measures exceeded .97. Correlations ranged from .74 to .81 for males and .79 to .91 for females. Classification agreement values ranged from 82.8% to 92.6%.
Results suggest general agreement among the selected methods of body composition assessments in both boys and girls with the exception that percent body fat in boys by Tanita BIA is significantly lower than skinfold estimation.
James J. McClain, Gregory J. Welk, Michelle Ihmels and Jodee Schaben
The PACER test is a valid and reliable assessment of aerobic capacity in children. However, many schools lack adequate space to administer the test. This study compared the utility of the standard 20m PACER test with an alternative 15m PACER protocol in 5th and 8th grade students.
A total of 171 students completed both PACER protocols in a counterbalanced design. Agreement between the two protocols was assessed with correlations, repeated-measures ANOVA, and classification agreement into the FITNESSGRAM
® healthy fitness zones.
The difference in estimated VO2max between the two tests was slightly larger for boys (5th grade, 1.32 ml/kg/min; 8th grade, 1.72 ml/kg/min) than girls (5th grade, 0.14 ml/kg/min; 8th grade, 1.11 ml/kg/min), but these differences are probably not of practical significance. Classification agreement was 88% for boys and 91% for girls.
Collectively, the results suggest that the 15m and 20m PACER provide similar information about aerobic fitness in youth. The 20m test is recommended when possible, but the 15m provides a useful alternative for schools with smaller gymnasiums.
Pedro F. Saint-Maurice, Greg Welk, Michelle A. Ihmels and Julia Richards Krapfl
The System for Observing Play and Leisure Activities (SOPLAY) is a direct observation instrument designed to assess group physical activity and environmental contexts. The purpose of this study was to test the convergent validity of the SOPLAY using temporally matched data from an accelerometry-based activity monitor.
Accelerometry-based physical activity data were obtained from 160 elementary school children from 9 after-school activity programs. SOPLAY coding was used to directly observe physical activity during these sessions. Analyses evaluated agreement between the monitored and observed physical activity behavior by comparing the percent of youth engaging in physical activity with the 2 assessments.
Agreement varied widely depending on the way the SOPLAY codes were interpreted. Estimates from SOPLAY were significantly higher than accelerometer PA levels when codes of walking and vigorous were used (in combination) to reflect participation in moderate to vigorous PA (MVPA). Estimates were similar when only SOPLAY codes of vigorous were used to define MVPA (Difference = 1.33 ± 22.06%).
SOPLAY codes of walking corresponded well with estimates of Light intensity PA. Observations provide valid indicators of MVPA if coding is based on the percentage of youth classified as “vigorous.”