Slow down your breathing and try to breathe from your belly. This is called diaphragmatic breathing and it helps fill your lungs more efficiently. It might sound counterintuitive, but most distance runners breathe too fast. By trying to take in more oxygen, you actually trap CO₂ in your lungs, which stops you getting the fresh oxygen you need. Slow it down. Long, relaxed breaths. You’ll find running becomes easier. Fast breathing also makes you tighten your shoulders and upper body as well as wa