Oxygen is so essential to human life that just four minutes without it can result in irreparable brain damage – and a further four can kill you. So what madness is the growing trend of intermittent hypoxic training (IHT), a form of exercise that involves deliberately denying yourself the amount of oxygen you need?
Sometimes, less really is more. Many top-flight athletes subject themselves to environmental stress to earn a competitive advantage; boxers, for instance, often train inside low-oxygen tents. A study in High Altitude Medicine & Biology found that IHT boosts performance by increasing levels of the hormone erythropoietin, related to the production of red blood cells. In essence, restricting oxygen while training helps you process it better under normal conditions, which can enhance your sprints, endurance and the recruitment of fast-twitch muscle fibres.
But what if you don’t have access to a hypoxic chamber? Well, a separate study suggests a zero-cost solution. Over eight sessions, athletes were asked to exhale and hold their breath before running for six seconds at a time; after that, they exhaled again to get rid of carbon dioxide accumulated in their lungs, before breathing normally to recover (that last bit’s pretty crucial if you don’t fancy fainting in the park). The scientists posit that performance gains could be attributed to improved muscle reoxygenation, better muscle recruitment and reduced fatigue.
This can be hard going, so only try it under the watchful gaze of a fitness professional. Master it, though, and you could see some breathtaking results...
Get More from Each Session with Three More Simple Hacks
01/ UP IN ARMS: Far from wasting energy, purposefully pumping your arms back and forth as you run will boost both the metabolic benefits and efficiency of your efforts. Swing and you’re winning.
02/ GET DOWN: A 2020 Brazilian study found that a single 30-minute downhill running workout helped athletes feel less fatigued during a flat-ground run two weeks later.
03/ HARD AND FAST: If you find yourself short on time, concentrate your cardio into eight 20-second bite-size sets at high intensity, resting for 10 seconds between each burst, for fast improvements to your oxygen uptake.