I have never worn a heart rate monitor during exercise in my life but I have always wondered what my readings would be. After researching max heart rates online I have found there are many formulas to calculate it but generally they dont take into account an individuals fitness level.

The basic formula seems to be 220 minus your age. I am 38 so that theoretically gives me a max heart rate of 185.

Without going into too many details, have any your personal experiences shown these formulas to be accurate or close to accurate ?