As we get older, our chest muscles get weaker, slowing down our respiratory system. The physiological sigh is a breathing technique to open up the alveoli for greater oxygen and carbon dioxide exchange. This strengthens the lungs, clears out toxins, slows the heart rate down, and calms the fight or flight response allowing us to regain control and promote strong lung health for deeper, fresher breathing. This exercise should be completed for 10 repetitions on a daily basis.