The higher up you climb, the thinner the air becomes. This means that with each breath you are taking in much less oxygen than you would normally. Breathing is therefore more difficult on a high mountain. Exercise becomes difficult because you have to breathe much more heavily to get the oxygen you need.
Answers
ANKUR
The higher up you climb, the thinner the air becomes. This means that with each breath you are taking in much less oxygen than you would normally. Breathing is therefore more difficult on a high mountain. Exercise becomes difficult because you have to breathe much more heavily to get the oxygen you need.