5 Tips to Beat High Altitude Sickness

Whether you’re travelling for a race, training or just on vacation, don’t let the elevation thwart your running.

“A bad hangover.”

That’s how Peter Hackett, Director at the Institute for Altitude Medicine in Telluride, Colorado, USA, describes the sensation of high altitude sickness, also known as Acute Mountain Sickness (AMS). The symptoms, which Hackett say can afflict any sea-level runner sleeping at 1800m or higher, include a headache, dizziness, feeling chilled, trouble sleeping, loss of appetite, nausea, fatigue and irritability. Not surprisingly, AMS becomes more common the higher up you go: at 2700m, 60 per cent of sea level residents will experience symptoms of AMS; at 4200m, the figure jumps to more than 80 per cent.

The exact cause of AMS is still unclear, but Hackett says the latest theory points to low levels of oxygen in the air (and thus, blood) that cause the brain’s blood vessels to dilate in an attempt to obtain more oxygen. This results in more blood in the brain, which can swell the brain slightly and trigger the hangover-like headache.

Any sea-level runner can fall victim to AMS, although certain factors – like your genetic makeup, how fast you changed altitude, and whether or not you have a current respiratory infection – can increase your likelihood. So whether you’re travelling to high elevation for a race, for a training session or simply want  to work out while on holiday in the mountains, here are five tips to combat the effects:

Give Yourself a Grace Period

“The worst thing you can do is to go up on the day of competition [or a hard training run] without allowing your body any time to adjust to the elevation gain,” says Hackett. “That has been proven to ensure you will lose the race.” Ideally, athletes should spend seven to 14 days at a particular elevation before competing, but Hackett says a three to five day acclimation period will also help improve performance, as most athletes will have overcome any symptoms of AMS at that point and their ventilation systems will have acclimated to the heights.

When booking your travels, consider an overnight stay at an intermediate altitude – say, stopping at 1600m  before ascending to 2400m. This can be “very helpful” with the adjustment process, says Hackett.

Do a Shakeout Run Immediately

“I’m a big advocate for going on an easy, 30-minute run as soon as possible once you arrive,” advises Megan Lizotte, a professional distance runner and running coach. Lizotte currently lives in San Diego in the US but returns to her hometown of Aspen, Colorado for about four weeks every summer, where she works with many sea level clients in town on holiday. “This initial shakeout run allows you to get a taste of what you’re in for and re-energises you from the travel.”

Engage Breathing Techniques

One of the first things you’ll notice at high altitude is the need to breathe faster and deeper, as your body needs to take in more oxygen than usual, explains Hackett. This can result in a general shortness of breath feeling that can last the first two to three days and is (not surprisingly) amplified with exercise.

When Lizotte sees a sea-level client gasping for air during an initial high altitude run, she encourages them to first relax their jaw “because that calms down a lot of other muscles connected to the rest of your body”. Then, she’ll have him/her breathe out with an ‘ssss’ or ‘th’ sound, which helps open the vocal chords. This technique is especially effective during hill repeats or other high-intensity workouts that generate lactic acid quickly, as it “takes the focus off of the pain and sense of panic that runners can feel,” says Lizotte.

Hydrate – Within Reason

Your body naturally dehydrates at high altitude, explains Hackett, stressing the importance of monitoring hydration levels and adjusting water intake accordingly.

On the flip side, he’s seen runners drink too much water, which dilutes sodium levels and can increase risk of hyponatremia, a condition that’s easily confused with altitude sickness, and can be fatal if untreated. “In reality you only need an additional litre to a litre and a half of water per day at altitude,” says Hackett. Two good rules of thumb to help you strike a healthy balance: first,  weigh yourself before and after a run so that you have an accurate understanding of just how much fluid you need to replace, and second, check your pee. Clear urine means adequate hydration while a dark stream spells dehydration.

Pace Well

VO2 max – the maximum amount of oxygen that an individual can use during exercise and a metric long used as a measure of running fitness – is markedly diminished at altitude, explains Hackett. This means that if you try to exercise at the same intensity at high altitude that you do at sea level, you are at a much higher percentage of your maximum effort.  Starting at around 1500m, VO2 max drops 3 percent per 300m of altitude gain.

“Athletes who don’t properly pace themselves at high altitude get exhausted and collapse,” warns Hackett, who has seen “a lot of comatose marathoners at 3600m because they don’t understand the acclimatisation process.”

His advice: take the first couple days at altitude especially easy. Understand – and accept – the fact that the altitude decreases your aerobic abilities and dial back your training plan and/or race goals accordingly. Simply put: “It is impossible to run 1600m at high altitude as fast as at low altitude.”

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