1. Online. FitBit. https://www.fitbit.com/global/us/products/smartwatches.
2. Online. Number of running and jogging participants in the United States from 2010 to 2021. https://www.statista.com/statistics/190303/running-participants-in-the-us-since-2006/.
3. Online. Polar H10 Heart Rate Sensor. https://www.polar.com/sg-en/sensors/h10-heart-rate- sensor.
4. Online. Zephyr HxM Heart rate Monitor. https://www.zephyranywhere.com/system/hxm.
5. Kayla-Jade Butkow, Ting Dang, Andrea Ferlini, Dong Ma, and Cecilia Mascolo. 2021. hEARt: Motion-resilient Heart Rate Monitoring with In-ear Microphones. arXiv preprint arXiv:2108.09393 (2021).