The entire amount of air that your lungs can hold is known as lung capacity. After we reach our mid-twenties, our lung capacity and function normally decline slowly. Some diseases, such as chronic obstructive pulmonary disease (COPD), can hasten lung capacity and function deterioration. This causes respiratory difficulties and shortness of breath. Obinna Nwogu, a fitness and health expert, says that focusing on breathing and training your lungs and respiratory muscles through breathing exercises, just like any other muscle in your body, will help you maintain and develop your crucial lung capacity.