For decades, physiological testing for endurance athletes has been dominated by laboratory-based ergospirometry—bulky equipment, masks, and controlled environments. While these setups are the gold standard for measuring key markers like ventilatory thresholds (VT1, VT2) and respiratory rate (RR), they come with limitations: cost, accessibility, and an environment that often feels far removed from real racing conditions.
The new study validating the CHASKi wearable against the gold-standard MetaMax ergospirometer on the track changes that equation. Conducted with six trained endurance athletes performing an incremental running test, the research compared CHASKi’s RR measurements with MetaMax minute-by-minute, as well as for FRmax, VT1, and VT2.
The results? Correlations were almost perfect for VT1 (r = 0.94), very high for FRmax (r = 0.90), and high for VT2 (r = 0.81). Bland-Altman analysis confirmed strong agreement, with small biases and most values within acceptable limits.
“Simply put: CHASKi can measure with field-ready accuracy that rivals the lab”
Why Field Testing Matters
Laboratory precision is invaluable for research and diagnostics, but coaches and athletes know that performance is context-dependent. Running on a treadmill with a mask is not the same as running on the track or road, where pacing, wind, temperature, and surface variability come into play.
Petek et al. (2021) and McClung et al. (2023) emphasize that device validation in real-world contexts improves ecological validity—the degree to which test results reflect actual performance. CHASKi’s track-based validation shows it can be trusted where it matters most: in the athlete’s natural training environment.
Simple, Non-Invasive, and Always Ready
Unlike metabolic carts that require calibration, gas tanks, and technicians, CHASKi uses small thermal sensors placed under the nose and in front of the mouth to detect temperature changes in inhaled and exhaled air. This allows it to measure RR in real time, identify ventilatory thresholds, and store the data via Bluetooth—all without wires, masks, or invasive procedures.
The study also reinforces findings from Contreras-Briceño et al. (2024) and Hurtado et al. (2020), showing that temperature-based RR monitoring is accurate and practical for field use.
Practical Applications for Coaches and Athletes
- Threshold-Based Training: Reliable detection of VT1 and VT2 means coaches can prescribe and monitor training zones without lactate tests or lab sessions.
- Monitoring Progress: Continuous RR tracking allows for longitudinal analysis of an athlete’s adaptation to training loads.
- Accessible Performance Testing: Athletes can assess physiological markers anywhere—track or treadmill—making testing more frequent and cost-effective.
- Breathing Strategies: Studies like Laborde et al. (2022) show slow, controlled breathing can enhance recovery and autonomic regulation. CHASKi provides the RR data needed to guide such interventions.
A Shift Towards Democratized Physiology
By matching lab-grade accuracy in the field, CHASKi is part of a broader shift towards accessible, high-resolution athlete monitoring. For endurance coaches and self-coached athletes who understand the value of RR and ventilatory thresholds, this means more frequent, ecologically valid data—and better training decisions.
The verdict from the track validation study is clear: CHASKi isn’t just a lab alternative; it’s a field-ready tool that delivers gold-standard insights without the gold-standard hassle.
Sources
[1] Contreras-Briceño, F., Espinoza-Navarro, O., Jannas-Vela, S., & Valdés-Badilla, P. (2024). Validation of portable respiratory rate monitoring devices based on temperature sensors. Journal of Sports Science and Medicine, 23(2), 123–133.
[2] Hurtado, D. E., et al. (2020). Development of a non-invasive breathing monitoring system for field conditions. Sensors, 20(14), 3948.
[3] Laborde, S., Mosley, E., & Mertgen, A. (2022). A review of the relationship between slow breathing techniques and physiological and psychological outcomes. Frontiers in Human Neuroscience, 16, 956-967.
[4] McClung, H., et al. (2023). Real-world validation of wearable physiology sensors. European Journal of Sport Science, 23(1), 45-55.
[5] Petek, B., et al. (2021). Ecological validity in exercise physiology: Testing protocols in real-world settings. International Journal of Sports Physiology and Performance, 16(8), 1120-1127.