Eli5 Why do we become out of breath and start breathing heavy if we do something exhausting if we are always breathing air in and out?

Question

I don’t get how we get out of breath if we are breathing air into our lungs all the time.

In: 0

Answer 1

Because you’re body is than working in aerobic mode to provide energy which means that your body needs oxygen to create energy for your exercises/doing.
You’re body tries to get as much oxygen as possible to maintain your exercises as long as possible.
See also citric acid cycle (CAC).