why when you breathe in and hold it you go out of breath?

Answer 1

Because when you hold your breath, the levels of carbon dioxide build up in your blood. This buildup will drop the pH of your blood, so it becomes slightly more acidic. The cerebrospinal fluid is the most monitored for blood pH range and will signal the medulla of your brain to begin breathing one again.

Answer 2

Removing the carbon dioxide is much more important. A scrubber that removes CO2 lets you rebreathe the same air much longer.

Your body is too smart, too well designed to let you kill it by intentionally not breathing. Breathing becomes involuntary before major damage can be done by CO2 poisoning.

Answer 3

I would vote for Answerman. If you demonstrate the voice difference breathing in Helium and then Argon, one gets light headed, dizzy from lack of oxygen, but not uncomfortable holding your breath. Perhaps since you are getting rid of the CO2, but not getting oxygen there is a signal from the CO2, but not lack of oxygen.

Answer 4

You must keep breathing in and out to replace the air because the air you expel has oxygen deficiency and an excess of carbon dioxide.

Answer 5

Because all your body cells require oxygen for respiration. If you hold your breath, you're not replenishing the supply and your body cells begin to starve for oxygen.

Answer 6

Because there is a buildup of CO2, which signals your brain that you need to breathe again.

Answer 7

The oxygen is changed to carbon dioxide

Answer 8

all of the oxygen in the air turns to carbon dioxide

Answer 9

because the O2 inhaled is exchanged within your lungs... you need to replenish and exhale the CO2