Question

As does the same exercises on a regular basis, they may find that their heart rate decreases with the same amount of activity, this is because
The muscles have acclimated to the work so now it's not as much work
The heart muscle has become stronger and can pump more blood and oxygen per beat
Both A & B
None of the Above

Answer 1

Good Morning!
 
Both contain truths. With the muscles accustomed to that amount of work, the effort is being reduced, since there is an increase of force. The work also assists in strengthening the heart, which is now more effective in pumping blood.
 
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