If you’ve ever had an asthma attack or respiratory illness, you know what it feels like to breathe shallowly because you can’t breathe more deeply. But even people who don’t have these conditions may breath shallowly without realizing it. Shallow breathing contributes to tension, fatigue, high blood pressure, increased heart rate and poor digestion. Through deep breathing exercises, you can override your body’s physiological responses to stress and illness and improve your energy and sense of well-being. There are many techniques for breathing deeply, but all improve the way you move air into and out of your lungs.