Assessing the validity of a novel core temperature monitoring tool at rest and during strenuous physical activity Article

Abstract

Core temperature information is important for guiding prevention and treatment measures. Developing new physiological monitoring tools that provide reliable core temperature information is critical for heat injury prevention. The ThriveHRI sensor system is being developed as an efficient core monitoring tool in a smartwatch platform. The current study compared the ThriveHRI sensor/smartwatch to an Equivital LifeMonitor and a rectal thermistor. This study aimed to determine if the ThriveHRI sensor system provides an accurate and precise estimate of core temperature at rest and during physical activity, representing strenuous occupational tasks at elevated temperatures in healthy adults. Twenty-five healthy, physically active adults (N = 14 males; N = 11 females) between the ages of 19–45 years volunteered. Participants completed multiple rounds of deadlifting and treadmill walking in an environmental chamber set to 43.3°C and 50% relative humidity. Participants alternated between performing deadlifts and walking on the treadmill for 35 minutes. Core temperature was monitored continuously via a Datatherm rectal thermometer, Equivital Eq02+LifeMonitor, and a ThriveHRI heat watch. A significant difference in bias between devices was found for easy walking (t(21) = 5.55, p < 0.001, g = 1.01), deadlift (t(19) = 3.60, p = 0.002, g = 0.73), and treadmill (t(16) = 2.42, p = 0.028, g = 0.60). A significant difference in precision between devices was found for easy walking (t(21) = 4.23, p < 0.001, g = 1.21), but no significant difference in precision between devices was found for deadlift or treadmill (ps ≥ 0.067). This study demonstrates the agreeability between the Equivital EQ02+ LifeMonitor, ThriveHRI sensor, and the rectal thermometer remains consistent as core temperature increases and exposure to a heated environment is sustained.