When checking my pulse while exercising it always seemd high. Just got a polar heart rate monitor for Christmas. According to all the charts my max heart rate should be about 170 (50 years old). While on the tread mill today I was running hard, but not dying and it was 186. As I slowed down to a fairly easy pace, able to talk speed, my heart rate was at 170-175. My resting heart rate is about 75. According to the charts, I should be exercising at a rate of 119 - 144. I would be doing a slow walk at that pace. Not sure where to set my target zone. Any suggestions?