Why do you need to breathe heavily after holding your for longer time and then release it?

Holding your breath for an extended period can lead to a buildup of carbon dioxide in the blood, which signals your body that it needs oxygen. When you release the breath, the sudden decrease in carbon dioxide levels can cause your body to go into a temporary state of hyperventilation, where it tries to rapidly compensate for the perceived lack of oxygen.This can lead to heavy breathing as the body works to normalize gas exchange and restore oxygen levels.