Can Someone please explain heartrate to me?!
 

Hi, All!

I was really hoping that someone could explain concept of the target heartrate for working out? I tried to look through some old A&P textbooks, but none of them really covered it in much detail.

It seems like the hardest you could work out (highest heart rate) would be best, but apparently that's not totally true. Is that right?

Any help would be very appreciated!!