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Altium i10 review

A device designed to mimic the effects of altitude training from your sofa? Joel Enoch takes a closer look at the Altium i10

The benefits of altitude training on endurance performance have been well-documented for decades. These gains have traditionally been reserved for the sporting elite – until now.

Over the last few years, scientists in Scotland have developed the Altium i10 (the ‘i10’ taking its name from Iten, the 2,400m-above-sea-level town in Kenya’s Great Rift Valley that’s produced many of the world’s best endurance runners). This rebreathing device reduces the saturation of oxygen inhaled from normal levels of around 21% to around 9-12% (equivalent to altitudes of 4,500-6,000m).

An Altium starter pack costs £499, and includes the i10 device, five CO2 scrubber cartridges, a Bluetooth Pulse Oximeter, nose clip, mouthpiece and an aluminium carry case (order at www.altium-i10.com).


Our testing involved two VO2max tests either side of a 28-day period, during which you use the Altium i10 for 6mins on/4mins off for 56mins every other day. While breathing through the device, your O2 saturation (sats) is monitored with an easy-to-use oximeter, which clips onto your finger and connects via Bluetooth to an app that shows your sats in live time.

On first use, we found the Altium i10 to be far more demanding than expected. The air feels damp and warm, the lack of oxygen producing a feeling as if the walls are closing in and, with HR rising about 30 beats, you feel rather like you’re exercising in a shrinking steam room. After some further calibration, though,
and more practice at regulating our breathing, we started to find the device easier to use.

The art is to keep sats between 80-85% – dropping more than this is challenging and isn’t shown to produce a greater effect. By halfway through the trial, most sessions felt relatively stress-free and it was easier to keep sats in the suggested range.


But does it work? Over the 28-day cycle we found it difficult to perceive any benefits in training, even though we did everything possible to keep training consistent. Nevertheless, the retest showed a 4% increase in total power and, while we could simply have been trying harder in the retest, the results showing a 2% increase in lactate threshold and an increase in efficiency (lower HR/VO2) are outside of an athlete’s control.

These findings are typical of average results from competitive cyclists in prior testing, which showed a 4% improvement in VO2max, a 3% increase in maximum work-rate, a 2% increase in efficiency and an 11% improvement in lactate threshold.

Respected exercise physiologist Dr Chris Easton of the University of the West of Scotland, who worked on the i10, believes. “The changes seen in lactate threshold/efficiency go beyond what you’d expect to see from training in a similar timeframe. Also untrained individuals might see even greater gains.”

We found using the Altium i10 just before bed sometimes affected sleep quality and it possibly made training feel harder. Yet the impressive numbers don’t lie and, while it may not hold the beauty of the Rift Valley, the Altium i10 might well be as effective (and is certainly less cumbersome than an altitude tent), making these performance gains available to endurance sports people anywhere at any time.

More research is needed (and we haven’t gone into the timing of altitude training in relation to racing), but the launch of the Altium i10 could potentially be a hugely significant innovation for endurance sportspeople of all levels.

Image: Secretstudio.net

Profile image of Matt Baird Matt Baird Editor of Cycling Plus magazine


Matt is a regular contributor to 220 Triathlon, having joined the magazine in 2008. He’s raced everything from super-sprint to Ironman, duathlons and off-road triathlons, and can regularly be seen on the roads and trails around Bristol. Matt is the author of Triathlon! from Aurum Press and is now the editor of Cycling Plus magazine.