Final answer:
To find your Max Heart Rate, you need to use your age.
Step-by-step explanation:
The personal variable needed to find your Max Heart Rate is your age.
To calculate your Max Heart Rate, you can subtract your age from 220. This formula gives you an estimate of the maximum number of times your heart should beat per minute during exercise.
For example, if you are 30 years old, your estimated Max Heart Rate would be 190 beats per minute (220 - 30 = 190).
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