Sign up for our newsletter


The high life: the Cyclist guide to altitude training

Stu Bowers
9 Jan 2018

These days you can train at altitude from the comfort of your own bed. We investigate the theory, follow the plan and assess the benefits

I am not Chris Froome. I have no designs on winning a summit finish at a Grand Tour, so altitude training is not something I’ve ever given much consideration to.

I know it can boost performance but, like most people, I don’t have the time or money to spend weeks up a mountain in the Alps.

There is, however, an alternative. Which is how I come to find myself pedalling a Wattbike at 2,850m above sea level in the heart of London.

I’m at The Altitude Centre, which is at an actual height of around 35m, but the hypoxic chamber I’m in simulates riding on high mountains.

Under the watchful eye of performance specialist James Barber, I’m experiencing what it’s going to feel like when I get out to Colorado for the 2017 Mavic Haute Route Rockies multi-day race.

Most of the Haute Route’s 800km distance takes place above 2,000m, including a number of visits to peaks above 3,000m.

Higher calling

That’s seriously high, and without acclimatisation I could easily end up a breathless wreck (or worse) somewhere in the Rocky Mountains.

That’s one reason I’m here. The other is that I’m keen to find out more about the physiological changes likely to occur in my body.

‘The main goal from altitude training is to improve your efficiency with the oxygen that you breathe,’ says centre manager Sam Rees.

‘The more oxygen you can get from the air into your blood and to your muscles, the greater your performance potential. Different modes of altitude training can be used to target specific physiological changes.

‘Sleeping and resting at altitude will target your oxygen-carrying capacity, increasing your red blood cell count.

‘Training at altitude can help to improve the efficiency at which your muscles uptake oxygen. The more oxygen your muscles can extract from the blood, the more energy they can produce via aerobic pathways, enabling you to sustain a higher intensity for longer.’

It doesn’t take long in the hypoxic chamber for me to realise just how much the altitude affects my performance.

As I pedal on the stationary bike I watch my power numbers on the monitor, and they’re nowhere near what I can usually manage.

I’m puffing and sweating, but the wattage numbers are what I’d expect to see for an easy recovery ride.

Crash course

I have a lot of adapting to do for my body to cope with the altitude, but I only have six weeks until the race, so this is going to be something of a crash course.

To speed up the process, Rees suggests I should sleep in a hypoxic tent for a few weeks too.

‘Exposing yourself to reduced levels of oxygen for a prolonged period during sleep stimulates a process known as erythropoiesis,’ he says.

‘It’s likely that after two to three weeks you’ll start to see these adaptations occurring. The more red blood cells you have, the more space there is for transporting oxygen around the body.

‘It’s widely accepted that more red blood cells correlates with an increase in performance.’

Erythropoietin (known as EPO) is a hormone secreted by our kidneys to generate red blood cells, and it can be stimulated by altitude training (of course, as Lance Armstrong knows, it can be stimulated chemically too, but that’s a whole other issue).

‘This performance improvement can be seen at both sea level and altitude,’ Rees adds.

‘Sea-level performance improves because the rider can make the most of the abundance of oxygen through their physiological adaptations, while at altitude the rider can cope better with the diminishing levels of oxygen in the air, as they’re able to use what’s available with far greater efficiency.’

For me this journey is more about the latter – getting through the high altitude in good shape – but it will be interesting to see how it affects my performance at sea level as well.

I’m already pondering how I broach the subject of the oxygen tent with my wife. It will also be interesting to see how the cats feel about sleeping at over 3,000m, too. 

Crunch time

A few days later I’m back in the chamber again. Barber gets me to perform a standard 20-minute functional threshold test, something I’ve done countless times, but never at 2,850m (the height The Altitude Centre’s chamber is routinely standardised to, equivalent to the highest passes in the Alps).

Ten minutes in, I know I’m in trouble. I’m in severe oxygen debt and even easing off considerably doesn’t seem to alleviate the build-up of lactic acid in my muscles, which feel like they’re being ripped to shreds by what is now only a fairly meagre power output.

By the end of the test I’m in a world of pain just to maintain what, on a normal ride, would be a pedestrian pace.

‘First big lesson learned there, I think,’ Barber says with a wry smile. I’d underestimated just how much the altitude would affect me. I now know to carefully meter my effort up to the ‘red line’, but not to cross it (at least not for any sustained periods) to avoid the impending crash in performance.

Barber usually prescribes high-intensity training sessions to extract the maximum gains from altitude sessions, but given the demands of the event I’m training for, my best plan of attack is to focus on longer intervals.

The process now is a straightforward one: I’ll keep turning up here, do my sessions as diligently as I can and hopefully my body’s ability to deal with altitude will be much improved by the time I fly to Colorado. Five weeks and counting. 

Does it work?

Each session edges me closer to being prepared for the real highs of the Rockies.

When I actually get to the event I’m keen to assess whether all the time spent sweating and cursing in a sealed room in central London has paid dividends, and I’d have to say that the answer is most definitely yes.

I don’t have any hard data so I can only speak on the anecdotal evidence of my experiences throughout the week-long event, but given how well my body coped with such an arduous test at altitudes proven to be highly detrimental to physiological performance, I’d vouch for its validity and effectiveness.

I witnessed many ‘less prepared’ riders struggle with the symptoms of altitude exposure, and listening to some of the stories around the dinner table each night reassured me that I was faring well above average, which

I could only attribute to the time I spent in the altitude chamber.

I’m now keen to try out my new powers at sea level, and more than anything I’m looking forward to putting the hurt on my regular riding buddies before the effects of my time at altitude wear off. 


Understanding altitude

Cyclist gets the lowdown on high training from Professor Louis Passfield of the University of Kent

Cyclist: How does altitude affect the body?

Professor Louis Passfield: Oxygen delivery in the body is compromised, so all aspects of performance that rely on oxygen tend to be compromised too.

Training hard, racing and recovery are all affected. However, the body adapts to altitude over a period of time. You can’t train as hard but some of the adaptations that altitude triggers can be beneficial.

You want your altitude training to emphasise the positive adaptations and minimise the negative consequences of not being able to train as effectively. 

Cyc: How high do we need to go?

LP: Generally above 2,000m. Some will feel the effects of lower oxygen availability at half this, while others need to go even higher.

There’s an upper limit beyond which altitude is mostly stressful and offers few of the benefits and more of the disadvantages.

This is around 3,000m, hence altitude training camps are usually held at between 2,000m and 3,000m. 

Cyc: How long does it take to acclimatise?

LP: The adaptations that altitude triggers can range from occurring immediately to taking several weeks or even months in the case of red blood cells.

Most of the short-term changes occur in the first few days, but full acclimatisation is really a process of two or three weeks and more.

Cyc: What are the effects and benefits of altitude training?

LP: Any aerobic or endurance exercise will feel disproportionately more stressful at altitude, and recovery will take longer.

One long-term adaptation is that the number of red blood cells in the body increases. The more red blood cells, the more oxygen is delivered to your muscles, meaning muscles can work harder. 

Cyc: How long do the effects last?

LP: In general the positive performance benefits are thought to last between one and three weeks after returning to sea level.

However, this is a contentious point because many scientists and coaches are sceptical that the purported benefits of altitude training outweigh the disadvantages.

Cyc: What is the current thinking on the best technique?

LP: Live high and train low is generally regarded as the most effective technique, but it’s difficult to achieve.

Where can you live at over 2,500m and train at sea level without using a helicopter to get around?

Therefore most athletes’ actual experiences of altitude training are really about compromising to something more like ‘live high and train a bit lower’. 

Cyc: For the average rider, are the benefits enough to warrant the effort and costs?

LP: Possibly not. Unless boosting your performance by a fraction of 1% is really meaningful to you, and you’ve explored the myriad other options in terms of exercise, nutrition and psychology, I’d leave altitude training to the pros.


Do it yourself

In reality, most of us lack the time and resources for lengthy trips to altitude. But what if you could high-altitude train without ever leaving home? Well, you can.

As well as offering its altitude chamber as an effective training facility to those city dwellers (or workers) close enough to regularly access it, The Altitude Centre, in London’s banking district (, also offers rental packages for equipment that’s easy and safe to use in your usual home-training environment.

Hypoxic air generator (including mask, connective tubes etc): from £225 per month. Altitude tent: from £50 per month.


Altitude theories

Live high, train low

This is theoretically the best combination. Rest and sleep are taken at high altitude (ideally at least 12 hours each day) to harness the benefits of acclimatisation, while training is conducted below 1,500m in an oxygen-rich atmosphere that allows for maximum effort.

Live high, train high

This is logistically more manageable and is how most altitude training camps work.

The constant exposure to high altitude means it’s harder to train at high intensity initially, but research has shown that after around four weeks it is possible to get past this and see considerable benefits.

Live low, train high

This would appear to be the weakest of the altitude training theories. As well as logistical issues, it is also difficult to achieve the desired intensities while riding ‘high’, such that an athlete might potentially even lose fitness training in this way.


Do it in your sleep

A hypoxic tent means you can sleep at altitude without having to leave the house 

First developed by Hypoxico in the 1990s, altitude tents can be a far easier and cheaper alternative to spending long periods of time living or staying at high altitude for acclimatisation.

Unlike ‘real’ altitude, an altitude tent does not reduce the barometric pressure of the air within. Instead hypoxic (oxygen-depleted) air from an altitude generator is pumped continuously into the tent, displacing the regular air inside along with any exhaled carbon dioxide.

The hypoxic air has about 12% oxygen content compared to the 21% that sea level air contains.

Using this system, altitudes of up to 5,000m can be simulated in the comfort of your own bedroom, allowing athletes to sleep or rest in a hypoxic atmosphere but train in their usual oxygen-rich environment.

Prolonged and regular use has been shown to have significant benefits to athletic performance, so much so that WADA (World Anti-Doping Agency) considered whether or not it should ban the use of altitude tents recently, although it was deemed too difficult to enforce.


The pro view

How important is altitude training to the WorldTour teams?

Marco Pinotti, performance coach, BMC Racing

‘It’s a tool that can help riders racing in the mountains and the Grand Tours, but only some riders respond well.

‘There are markers we can check to see if it has worked, but the real check is the road – the race results after they return to sea level.

‘Often when they come back the first race is not so good, and then they perform well maybe two or three weeks after.

‘Every time a rider goes to altitude we learn something about their body, and how to use this tool better in the future.

‘We go to Tenerife or Sierra Nevada, maybe Mount Etna in Sicily, but weather conditions mean it’s logistically difficult to organise so we usually only take one single rider or a small group. Never the whole team.’


Jon Baker, coach, Dimension Data

‘We don’t go as a team to altitude – we take small groups, often to Tenerife, but some riders prefer Boulder, Colorado.

‘It’s hard to find locations that don’t have snow above 2,500m for most of the year.

‘Altitude training isn’t a magic bullet. The research supports its benefits, but there are negatives as well – reduced sleep, and it’s harder to train at high intensity.

‘Riders’ responses are an individual thing. My job is to understand the physiological profile of the rider and how they adapt.

‘It’s hard to provide actual numbers but I would say a 20 watt improvement [in threshold power] would be a brilliant result.

‘Realistically we would see more like 5-10W.’

Read more about: