If you follow any pro cyclist on social media, chances are you’ve seen a photo or two snapped at altitude. Since Team Sky popularised altitude training camps by setting up shop in Tenerife, they have become all the rage within the peloton, with professional outfits flying their riders out on multi-week-long jaunts thousands of meters above sea level.

But can that relatively short window really make the difference between first and second in a race? And is altitude training reserved purely for the pros, or can the average club rider feel the benefits, too?

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The Bora-hansgrohe team of Peter Sagan is one of the many WorldTour squads to use altitude training camps, taking its riders to the Sierra Nevada in southern Spain or East Tyrol in Austria - but it’s not the whole squad, only a handpicked selection of riders actually head for the hills.

“It’s one training method to prepare the GC-focused racers, as well as riders for the Classics at the beginning of the year,” says Dan Lorang, a sports scientist and coach for Bora-hansgrohe. “In the first year we did it, we took all the riders and saw some of them react quite well with the performance, but for some other guys we had a feeling that there was a decrease. Our goal is to work with small groups and only with the guys who are really responding well to it.”

Roger Hammond’s Dimension Data team also takes a selection of riders on altitude training camps, reinforcing Lorang’s assertion that every rider responds differently to the demands of training above sea level. “There are receptors and non-receptors,” he says, “so you have to work out who it works for.

“At the moment, we’re doing a lot with the GC riders, so Louis [Meintjes] and the climbers. They’re on an altitude programme where the coaches are there, they live with them and monitor them at altitude. There’s no point in taking Cav [Dimension Data’s star sprinter Mark Cavendish] to altitude because it would just affect his peak power.”

Louis Meintjes Giro d'Italia

The African team’s directeur sportif was an early adopter of the training technique during his own cycling career, investing in a hypoxic chamber (essentially an altitude-simulation tent) on turning professional in 1998 and sleeping in it for stints throughout the season.

“When I turned professional, they didn’t even do training camps, let alone altitude camps. I discovered the benefits when I did the Junior World Championships in Colorado Springs and stayed there for about five weeks. When I came home, I could just win any bike race I wanted for about a month”

“When I turned professional, they didn’t even do training camps, let alone altitude camps,” says Hammond. “I discovered the benefits of altitude when I did the Junior World Championships in Colorado Springs and stayed there for about five weeks. When I came home, I could just win any bike race I wanted for about a month. For me it was a huge transformation in performance.

Roger Hammond Paris Roubaix 2004

“While people were buying other ‘products’, I started experimenting with sleeping at altitude. I would jump in the tent in November and let it build up slowly for about six weeks. After that I was able to top up between races. For most of my career I had a tent in my bedroom – my wife refused to sleep in it after about two weeks!”

But what actually happens to riders like Roger Hammond, Louis Meintjes and Peter Sagan when their body reacts to altitude? And how does that translate to a boost in performance?

The science of altitude training

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“When you look at altitude training, there are two main styles,” explains Craig Stevenson, performance director for the UK-based sports nutrition brand OTE Sports. “The first is the traditional one that you hear about the pro riders doing, where they’ll go off to a training camp and do the sleep high/train low technique.”

This really is as simple as it sounds. Professional riders will stay up in the mountains for weeks at a time, starving their bodies of oxygen during rest and post-ride recovery. This strain causes the hormone erythropoietin (EPO - yes, that EPO), to naturally produce more red blood cells. These are then used by the body to transport oxygen to muscles.

Tenerife’s Mount Teide has become the go-to destination for altitude training. On any given week in winter or spring, you could find riders from a whole host of WorldTour teams staying at the 2,164m Parador de Cañadas del Teide, using the 45km climb that winds up to the hotel to train and taking advantage of the favourable weather conditions of the Canary Islands.

“They have long term exposure to a hypoxic environment - so a low level of O2,” says Stevenson. “That stimulates adaptations in the body, with the main one being a central adaptation in terms of increased amounts of haemoglobin [the protein found in red blood cells], which effectively increases the body’s ability to transport and utilise oxygen.”

“Professional riders will stay up in the mountains for weeks at a time, starving their bodies of oxygen during rest and post-ride recovery. This strain causes the hormone erythropoietin (EPO - yes, that EPO), to naturally produce more red blood cells”

That, according to Hammond, helps make big efforts easier, key when crunch time arrives in the general classification of a Grand Tour. “Sleep high-train low is all about the altitude affect,” he says. “Your body gets used to making those efforts with less oxygen.”

In layman's terms, this means that professional riders will have more red blood cells in their body to transport oxygen around it, and will ultimately use less energy in doing so. When it comes to a race, this can translate to a higher functional threshold power (FTP), VO2 Max, and the ability to ride harder and for longer when the competition heats up.

The ‘adaptation’ isn’t permanent though, which is why one rider could end up going on multiple altitude camps in one season. “The benefits last for two-to-three weeks,” adds Stevenson. “They go there, get red blood cells, might perform really well, and then it starts to fade away.”

But what if you don’t have the schedule or budget of a professional cycling team? Is there a way of getting the benefits of altitude training without using up your entire allocation of annual leave, or turning your bedroom into a campsite? In short, the answer is... kind of. This is where Stevenson’s second route to altitude training comes in.

An alternative altitude

Across the UK, a number of specialist gyms, universities and performance centres have their very own hypoxic chambers, including OTE Sports in Leeds. Similar to Roger Hammond’s tent – only on a slightly bigger scale and with the odd static bike, rowing machine or treadmill thrown in – the rooms simulate altitude by removing oxygen from the air like a reverse air conditioning unit. OTE’s chamber can simulate an altitude up to 5,750m.

“We don’t get people to sit in a chamber for ten days at a time, so that adaptation and change in red blood cells clearly isn’t going to happen,” says Stevenson. “What we’re actually going for is the peripheral adaptation. We use the altitude not as what you traditionally class as acclimatisation to altitude, but as a means to overload your body more.”

OTE altitude training session

By exercising with less oxygen in the air, your anaerobic system is put under a lot more strain - so much so that if you did an interval session in the chamber, it would be very hard to replicate that extent of stress without being at altitude, according to Stevenson.

“When you generally train at intermittent hypoxic exposure, you get a stronger adaptation post-training than you would do normally – you get increased oxygen utilisation, while you’ll also find that your lactic tolerance has been increased, too,” he adds.

In essence, training in a hypoxic chamber reverses the traditional sleep high-train low philosophy - instead, riders are taking interval training to the next level by training high and sleeping low, as they would normally. Sessions are run between 2,500m to 3,500m, with the sweet spot at 3,000m – 800m higher than the highest point of this year’s Tour de France’s highest point, the Col de Portet on stage 17. At this altitude, there is roughly a third less oxygen than at sea level.

“Training in a hypoxic chamber reverses the traditional sleep high-train low philosophy - instead, riders are taking interval training to the next level by training high and sleeping low”

“For a 45-minute session [in the hypoxic chamber], you’d be hard pressed to replicate that in an hour and a half interval session at sea level – the reality being that you probably couldn’t sustain the intensity for an hour-and-a-half anyway,” says Stevenson, who claims a club-level cyclist could see gains of up to 30 per cent on repeated sprint ability versus a sea-level training programme.

The benefits will also last, Stevenson says - unlike those seen within receptors on sleep high-train low camps: “It’s an actual structural change in the body,” he says. “If you use it as a tool to train and do six weeks, providing you’re still training thereafter and giving yourself high intensity work, it’s not going to disappear - it’s a training method as opposed to a short term adaptation.”

Mont Blanc

OTE runs coach-led training sessions in the chamber and advises riders to schedule at least one session a week for a minimum or four weeks in order to see the desired adaptations. “I get some of my own athletes to do it at the end of the season,” says Stevenson. “When the weather is really bad, we do it twice a week for four-five weeks, and when we go back to a normal training block they can normally deal and tolerate more training than what they could have done without that altitude block.”

But if it’s such a revolutionary training method, why don’t we see snaps of the professionals live from the hypoxic chamber? Well, they’re generally already pretty close to their physical limit, and so there’s less scope for improvement, according to Stevenson.

“Their gain [from a training block of altitude interval sessions] might only be 1-2 per cent,” he concludes. “They also aren’t short of time, so it would just be adding the icing to the cake, but they’ve got the option and the budget to go away and stay away for ten days, which for them might be a larger adaptation.”

It’s fair to say that altitude training isn’t for everyone. Although proven at pro level (for some riders), training camps in Tenerife and tents for the bedroom come at a cost. For the time being, the keen club rider in search of performance gains will probably have to stay a bit closer to home and settle for dedicated hypoxic sessions, but if you're looking to take your riding to the next level, altitude training could be the answer.