Effectiveness of the modified progressive aerobic capacity endurance run test for assessing aerobic fitness in Hispanic children who are obese

Authors: GRAHAM, MARILYNN - University Of Houston; BUSH, JILL - University Of Houston; OLVERA, NORMA - University Of Houston; PUYAU, MAURICE - Children'S Nutrition Research Center (CNRC); BUTTE, NANCY - Children'S Nutrition Research Center (CNRC)

Submitted to: The Journal of Strength and Conditioning Research
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 9/1/2014
Publication Date: 10/1/2014
Citation: Graham, M.H., Bush, J.A., Olvera, N., Puyau, M.R., Butte, N.F. 2014. Effectiveness of the modified progressive aerobic capacity endurance run test for assessing aerobic fitness in Hispanic children who are obese. The Journal of Strength and Conditioning Research. 28(10):2880-2887.

Interpretive Summary: The Progressive Aerobic Cardiovascular Endurance Run (PACER) was developed using normal-weight children, however, it is used to evaluate aerobic fitness in all children irrespective of obesity status. In this study, we evaluated the PACER test in obese Hispanic children and propose a modified PACER (MPACER) to measure aerobic fitness in obese children. We measured the physical fitness in 39 obese and 16 normal-weight children, ages 7-12. Test outcomes included test duration (min) and exercise heart rate (first stage and peak heart rate) for the PACER and MPACER. PACER test lasted 1.6+/-0.6 min for obese children and 3.1+/-1.3 min for normal-weight children. MPACER duration was 3.6+/-0.6 min for the obese group and 5.3+/-1.2 min for the normal-weight group. Importantly, the heart rate was more physiological in the MPACER; the peak heart rate was below the anaerobic threshold during the MPACER. We found that the MPACER is a better instrument than the usual PACER to measure the aerobic fitness of Hispanic children who were normal weight or obese. The new modified method (MPACER) can be used by physical educators, personal trainers, and others who are measuring the aerobic fitness of children.

Technical Abstract: The purpose of this study was to evaluate the effectiveness of the progressive aerobic capacity endurance run (PACER) and a newly designed modified PACER (MPACER) for assessing aerobic fitness in Hispanic children who are obese. Thirty-nine (aged 7-12 years) children who were considered obese (= 95 th body mass index [BMI] percentile) and 16 children who were considered normal weight (<85th BMI percentile) participated in this study. Performance outcomes included test duration (in minutes) and exercise heart rate (HR) (first-stage and peak HR) for each test. Ninety-five percent confidence intervals and independent t-tests were used to assess differences in primary outcomes. Mean PACER test duration was 1.6+/-0.6 and 3.1+/-1.3 minutes for children who were obese and normal weight, respectively. Modified PACER duration was higher than 3 minutes for the obese (3.6+/-0.6 minutes) and normal weight (5.3+/-1.2 minutes) groups. Children first-stage HR, expressed as a percent of peak HR, was above the predicted anaerobic threshold during the PACER, but below the anaerobic threshold during the MPACER. Relative first-stage HR was not significantly different between groups for the PACER, but they were significantly different between groups for the MPACER. In conclusion, the MPACER was a better alternative than the PACER for assessing aerobic fitness in Hispanic children who were normal weight and obese. When validated, this modified field test could be used to assess aerobic fitness in Hispanic children, particularly those who are overweight or obese. Additionally, the study provides evidence in which physical educators, personal trainers, and others most apt to assess aerobic fitness in children who are obese, should modify tests originally designed for the population who are normal weight.