Heart Rate Monitors

I have a Polar F11 and love it. I've never had any issues with it, I've had it about 3 years now. I can't work out without it, I feel naked without it. If you get one invest in one with a chest strap. They're more acccurate and they can also transmit to cardio equipment. So when I'm running on the treadmill my heart rate will show up on the display without having to hold onto the handles.