try to “inflate” your stomach as you breathe in, while keeping your chest relatively still. Then contract your abdominal muscles on the exhale. Not only will this give you more oxygen per breath, it will eventually strengthen the diaphragm. A stronger diaphragm means you get more oxygen with each breath, so your brain won’t need to divert any away from your muscles, meaning that you get tired less easily. … A study on cardiac patients showed that this type of breathing leads to improved exercise performance and decreased shortness of breath, and it’s also been linked to lower blood pressure. This is the reason that so many coaches recommend breathing practice as a shortcut to sports-based superpowers.
When upright, most people are habitual chest breathers: We use a shallow form of respiration that makes use of only the top part of the lungs. In reality, most of the blood vessels that take up oxygen are in the bottom, neglected half. Since so much lung power is going to waste, we get less oxygen, and as a result, we’re all breathing more rapidly than nature intended us to.
Chest breathing also tends to upset the blood’s oxygen/carbon dioxide balance and can lead to headaches, fatigue, anxiety and even panic attacks. According to one expert, you’re also potentially suffering from sweaty palms, difficulty relaxing, heightened pain perception and general fatigue.