Nose breathing while running, has been linked with helping stimulate a better exchange of gases However it may surprise some, but I NEVER breath through my nose when running. For me and many runners We struggle to get enough air through our nostrils, so this subject is often contentious WHEN TO USE NOSE BREATHING ? Too many runners train in ‘the grey zone’, too fast for an easy run but too slow for a hard run. Nose breathing is a natural way to ensure your easy runs are easy, because you can not