For sports sensor accuracy validation studies The scientific paper: Rahel Gilgen-Ammann, Theresa Schweizer, Thomas Wyss, Eur J Appl Physiol. 2019 Jul;119(7):1525-1532., RR interval signal quality of a heart rate monitor and an ECG Holter at rest and during exercise https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=&cad=rja&uact=8&ved=2ahUKEwiKos3IhuH4AhWF_bsIHfGlD2kQFnoECAIQAQ&url=https%3A%2F%2Fwww.ppdb.ehsm.ch%2Finf2%2Frm%2Ff.php%3Ff%3D20200416162130_5e9869eab833b.pdf%26n%3DGilgenAmmann_RRIntervalSignalQuality_2019.pdf&usg=AOvVaw23MOAobT8so8HFGAdgdcPo used a AR12plus Holter ECG device: https://www.medicaldevicedepot.com/Medilog-AR12-Plus-p/1.35001.htm and compared it to a Polar H10 chest …