Evaluating The Validity Of Heart Rate Measured By The Rhythm During Mountain Biking

Abstract

The Rhythm armband is a wearable device that measures heart rate, and it is unknown whether it is valid throughout rough terrain, such as mountain biking. PURPOSE: The purpose of this study was to investigate the validity of heart rate (HR) measurement by the Rhythm armband against the criterion, the Polar H7 chest strap while mountain biking. METHODS: A total of sixteen healthy adults (males = 8, females = 8, 24.69 ± 4.44 yrs, 171.45 ± 8.9 cm, 74.23 ± 21.07 kg) were recruited to ride mountain bikes on a 3.22km, beginner-level mountain biking trail at the McCullough Hills Trailhead in Henderson, NV. Participants were fitted with both a Polar H7 HR monitor and the Rhythm HR monitor and rode 1.61km away from the trailhead and 1.61km back to the start of the trailhead. RESULTS: The lower and upper limit of agreement (LoA) range was -412.25 and 451.59, respectively, and the mean absolute percent error (MAPE) was 59.82%. The Rhythm armband also demonstrated an ICC = 0.008 (95% CI = -0.006, 0.022, p-value < 0.140). CONCLUSIONS: The Rhythm armband demonstrated low correlation and a low level of agreement against the Polar H7 chest strap, suggesting that The Rhythm is not a valid measurement of HR during mountain biking.