Keywords: Polar RS400 Heart Rate Monitor.jpg A heart rate monitor showing chest strap and watch own 2009-03-18 Bill Ebbesen aka Atomicbre wikipedia en Atomicbre Original upload log en wikipedia Kelly CommonsHelper en wikipedia Polar+RS400+Heart+Rate+Monitor jpg 2009-03-18 15 43 Atomicbre 2440×2180× 789295 bytes <nowiki>Photo by Bill Ebbesen </nowiki> Heart rate monitors |