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This “180 Formula” enables athletes to find the ideal maximum aerobic heart rate in which to base all aerobic training.
To find your maximum aerobic training heart rate […] Subtract your age from 180.
Initially, training at this relatively low rate may be difficult for some athletes. “I just can’t train that slowly!” is a common comment. But after a short time, you will feel better and your pace will quicken at that same heart rate. You will not be stuck training at that relatively slow pace for too long. Still, for many athletes it is difficult to change bad habits.
My pace at low heart rate went form 6 minutes per km to less than 5 minutes per km.
Once a maximum aerobic heart rate is found, a training range from this heart rate to 10 beats below could be used.