Validation of the Garmin Forerunner 920XT VO2max Estimation and the Polar RS300X Fitness Test

Abstract

Several fitness watches have developed tests to estimate VO2max to provide important data and save money by reducing the need for a metabolic cart. Some watches provide results based on heart rate (HR) while others combine HR data with global positioning satellite (GPS) data. The purpose of this study was to validate VO2max from the fitness test on a Garmin Forerunner 920XT (HR and GPS-based) and a Polar RS300X (HR-based) fitness watch against a maximal graded exercise test (GXT) using a metabolic cart.

10 male and 7 female college students (age = 21.5 ± 2.9 years) participated in this study. Session 1 consisted of completing the Informed Consent, PAR-Q, and Garmin fitness test. Session 2 comprised the Polar fitness test and a maximal Bruce treadmill test using the metabolic cart. Maximal performance during the Bruce test was validated by obtaining age-predicted HRmax. Data were analyzed using one-way ANOVA with a significance level of p < 0.05. Secondary analysis was conducted using Pearson correlations.

VO2max from the Garmin, Polar, and metabolic cart tests were 47.82 (± 9.60), 45.53 (± 5.42), and 45.63 (± 8.84) ml/kg/min, respectively. ANOVA tests revealed no significant differences between any of the tests (p = 0.6 between the Garmin and the metabolic cart; p = 0.3 between the Polar and the metabolic cart). Pearson correlations revealed that the Garmin test was highly correlated with r = 0.83 (p < 0.001) while the Polar test was strongly correlated (r = 0.65, p < 0.001).

The findings indicate that Garmin and Polar fitness tests may serve as an adequate substitute for testing using a metabolic cart. The Garmin test may be a more appropriate choice as the correlation was stronger and the Polar test tended to overestimate VO2max.