<span>50 years85-145 beats per minute170 beats per minute</span>
Answer:
I'm still trying to figure that out for my self
Detraining. (example) <span> They began a </span>training program and then stopped exercising after 4 weeks.<span> They quit exercising for the next two months. They were tested were found to have lost all of their aerobic gains and returned to their original fitness levels.</span>.
