Breathing while running should feel steady and controlled rather than fast and shallow. Most runners do best by taking deeper breaths from the diaphragm instead of quick breaths from the chest. A simple approach is to inhale through the nose or mouth and exhale through the mouth in a relaxed rhythm while you run.
Deep, slower breathing helps move more air in and out of the lungs with each breath. This can improve oxygen exchange and reduce the effort your breathing muscles need to work. Rapid, shallow breathing may make you feel out of breath faster and can increase the work of breathing during exercise.
Many runners also find it helpful to match breathing with their steps. For example, you might inhale for two or three steps and exhale for the same number of steps. This rhythm can make breathing feel more natural and keep your pace steady during longer runs.
If you often feel very short of breath while running, try slowing your pace and focusing on deeper breathing from your abdomen. Persistent breathlessness, chest tightness, or wheezing during exercise should be evaluated by a healthcare professional, such as a pulmonologist or sports medicine specialist.