Compared to the value measured at sea level, when a subject works at the same work rate at 3,000 meters altitude, the heart rate is
A) higher.
B) lower.
C) the same.
D) dependent on the conditioning state of the subject.

Question

Quizplus · Accepted Answer

At higher altitudes, the air pressure and oxygen content decrease, making it harder for the body to get the oxygen it needs. To compensate for this, the heart rate increases to pump more blood and get more oxygen to the working muscles. Therefore, the heart rate is higher at 3,000 meters altitude compared to the value measured at sea level.

Compared to the Value Measured at Sea Level, When a Subject