S0RA
Answered

MHR should be calculated

ADuring an intense exercise routine
BPrior to an initial exercise routine
CImmediately following the exercise routine
D20 minutes after an exercise routine

I'd really appreciate your help! Thanks! ^^

Verified Answer :

Maximum heart
rate should be calculated immediately after an exercise routine. Maximum heart
rates vary with age and the exercise activity performed. It refers to the
maximum capacity of the heart to supply blood throughout its entire system.
Maximum heart rates are also based on exercise intensity/target zones to keep
track how an individual is performing or should perform in an exercise
activity. It is estimated to be calculated as 220 minus your age. Why 220?
Because it is the only maximum number of beats per minute that the human heart
could actually perform in a lifetime.