The marathon is still the distance by which all runners are measured. With European travel even easier thanks to EasyJet and Eurostar, we’ve got access to Berlin, Paris, Amsterdam… We’re not confined to the luck of the draw in the London lottery.

We’ve been helping both professional and amateur runners train for personal bests in marathons since The Altitude Centre first started in 2003, and every year we meet someone who’s take marathon challenges to a new level.

This year, we’ve been working with Andrea Mason, who – with her group The Neverest Girls – is completing The Tenzing Hillary Everest Marathon in May this year.

Andrea, who lives at approx. 1,500m altitude in Chamonix in France, is completing the challenge with seven like-minded women to raise money for breast cancer charity ‘A Chacun son Everest’ (meaning ‘Each Has their Everest’).

Despite living at altitude, and the Everest Marathon being almost all downhill, descending from Everest Base Camp (5,364m, 10.7 per cent oxygen) finishing at Namche Bazaar (3,446m, 13.5 per cent oxygen), this is a huge challenge.

‘Just because it’s predominantly downhill doesn’t mean this race is easy,’ says Andrea. ‘We’ve been training for over a year, and whilst living in Chamonix helps, we will still need to take it very slowly across the icy, rocky terrain.

‘We’ve been mainly running, but also cycling, swimming, skiing, doing yoga and doing some fitness classes. Cross training helps build all-round strength, minimising the risk of injury.

‘Using The Altitude Centre’s Sleep System means I can sleep in altitudes of around 4,200m (the combined altitude of the Sleep System at 3,660m and the 1,500m altitude of Chamonix), which is essential pre-acclimatisation for the Everest Marathon.

We wish The Neverest Girls the best of luck with their challenge, and will be following their progress on Twitter, @NeverestGirls.

If you’re interested in training for The Tenzing Hillary Everest Marathon in 2015, start training now with a Mountaineering Consultation.

With the 2014 Virgin Money London Marathon just two weeks away, it’s not too late to aim for extra performance gains. A session of passive Intermittent Hypoxic Exposure (IHE) allows you train your body without doing any exercise.

Taking you up to 5,000m (10 per cent oxygen compared to 20.9 per cent at sea level), IHE encourages a very similar response to exercising at 3,000m without any risk of injury. Call us on 020 7193 1626 or click here to book in before race day.