The secret to running far and fast is as much in the lungs as it is in the legs. If you’ve got a runner friend, you’ve probably heard them banging on about their VO2 max ― something the University of California Davis Health describes as “the gold standard measure of aerobic fitness”. This measures “the maximum rate of oxygen consumption measured during incremental exercise”, their site continues. I’ve been slowly getting back into running and I think my VO2 max is rapidly improving.But it wasn’t until I tried a military-style breathing pattern that I realised I could influence how much oxygen my body got outside of my lung capacity ― and went on to run my first half-marathon in years. How does the military breathing technique work?Most of us think of breathing as a one-in, one-out process (meaning you inhale for as long as you exhale). But as former Navy SEAL and strength and conditioning specialist Stew Smith wrote for US military news and information site