Background/Purpose. Aerobic capacity is generally recognized as an important component of health-related fitness. A variety of field-based measurement techniques, many requiring submaximal exercise, have been developed for use in a school setting to estimate aerobic capacity or simply classify an individual's fitness level. A relatively new development in the assessment of aerobic capacity is the use of non-exercise models. Some non-exercise methods have been shown to have similar reliability and validity to submaximal prediction tests, yet require no physical exertion. The Polar Fitness Test is one example of a non-exercise method of estimating aerobic capacity using resting heart rate, heart rate variability (HRV), gender, age, height, body weight, and self-reported long-term physical activity as predictor variables. A specially designed heart rate monitor (HRM) measures heart rate and HRV and utilizes an internal algorithm to predict aerobic capacity. The technique has been shown to be a valid and reliable predictor of aerobic capacity in adult men and women, but limited information is available for use with children and adolescents. The purpose of this study was to examine the equivalency of the Polar Fitness Test and the PACER as a predictor of aerobic capacity in adolescents.
Method. Participants included 20 students from a small rural high school who volunteered for the study. Each participant completed the PACER and Polar Fitness Test according to recommendations. Scores on each test were converted to estimates of VO2max. The Polar F11 HRM was used in the administration of the Polar Fitness Test. All testing was completed during the first month of the school year.
Analysis/Results. The Pearson correlation between PACER predicted VO2max and Polar F11 predicted VO2max was r = 0.62 (p < .05), however a paired t-test indicated a significant difference between PACER predicted VO2max and Polar F11 predicted VO2max. Mean VO2max values predicted from the Polar F11 were significantly lower than similar values predicted by the PACER for both boys and girls. Effect size for the difference was calculated as 1.61, indicating a large effect. In order to determine the classification equivalency of the two tests, coefficient kappa was calculated, resulting in a value of 0.16 which was interpreted as slight agreement. A Bland-Altman plot confirmed the under-prediction of the Polar Fitness Test compared to the PACER.
Conclusions. It was concluded that the Polar Fitness Test and the PACER do not provide similar information about aerobic capacity for adolescents.