For decades we've been told to calculate our peak heart rate (a gauge of how hard to exercise) by subtracting our age from 220. But now researchers from Northwestern medicine say that formula yields numbers too high for women- meaning we've been working too hard! Their new female- friendly math: Multiply your age by 0.88, then subtract that number from 206. Stay within 65-95% of that peak heart rate to get the most bang for your cardio buck. HOW TO TELL IF YOUR HITTING THE TARGET: Stop mid exercise and count your pulse for 15 seconds, then multiply by 4 to get your heart rate. If it's too high, slow down, if it's too low and you feel good, step up the pace.
Health Magazine November 2010