Humon: Measuring oxygen levels is the fitness metric everyone is going to want

Meet the wearable you wear on the leg that's being built for endurance athletes
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In our Wareable 50 run down of the hottest trends to go big in 2017, we tipped hardcore fitness metrics to truly go mainstream. Fitbit led the way last year introducing VO2 Max testing with its Charge 2 fitness tracker. Humon, a startup based out of Boston feels that while it's a positive thing that companies like Fitbit are offering users more fitness data, there's still some work to do to educate users what it all means and how it can help you get fitter.

That's why it developed a wearable specifically for endurance athletes, although it wasn't always the intention to be a wearable when the idea was first hatched. "I was at MIT Sloan and became very obsessed that biology and technology would intersect and help you learn more about your body," Humon's co-founder Alessandro Babini told us.

Read this: Why hydration monitoring is about more than fitness

"MIT Sloan were also convinced in doing research on this topic so we partnered with them and did a nine-month research project with the goal to identify how the two subjects could be brought closer together.

"After the research we found that the only people that were going to adopt these technologies were the athletes and endurance athletes. So I'm talking about runners, cyclists and triathletes. The problem is that they don't have access to the information they need to know how hard to push themselves. Only the endurance athletes really knew what information they needed."

For elite eyes only

Humon: Measuring oxygen levels is the fitness metric everyone is going to want

The result of that research was the Humon Hex, a wearable you wear around the mid thigh area. There's no calibration or need to tap in data like your age, height, weight etc on the companion app. It uses an optical sensor to shine a few different coloured lights into the muscle and reads the absorption of the light. Based on that measurement it can then look at the level of blood in the muscle tissue and is able to measure oxygen saturation in the blood. The Hex then analyses this measurement to give training insights and uses the data to help formulate a personal AI-powered coach.

"By wearing the device directly on the quad, the biggest muscle that is exerted the most during these endurance sports, we are able to tell how your muscles are reacting," Babini explained. "We can tell you in real time about how you are warming up, how far you are from your limit, how you are recovering and when or not you should keep pushing yourself."

The tech is inspired by the pulse oximeter a device commonly used in hospitals to measure blood oxygen. The difference here is that Humon looks at oxygen concentration in the muscles directly and not in the arteries like an oximeter. While it's recommended that you wear it on the lower body, Babini has found that early testers have been calling for the Hex to be used away from the legs as well.

"The device has been built to be worn on the thigh because of the market we are going after, but it does work on any muscle", he said. "So we have a bunch of people who are wearing it on their triceps and doing press ups and trying to see the optimal recovery time doing push-ups sets. A bunch of crossfitters and weightlifters have asked us for sensors in t-shirts that can monitor muscles in the upper body and that's something we are going to look at in the future."

Getting Hex up to scratch

Humon: Measuring oxygen levels is the fitness metric everyone is going to want

While Babini told us that it has no intentions to create an FDA approved device to give you medical recommendations, it has had to put the wearable through a rigorous testing process to get the measurement accuracy right and could truly benefit endurance athletes.

"The product was vetted clinically. The study is still going so I'm not allowed to discuss by who," he said. "In terms of absolute value, we are 94% accurate. In terms of physiological change, we are spot on. We have been working with a lot of professional athletes runners, cyclists, triathletes as well as gyms and athletes from different kinds of sports. We've had NFL players and basketball players test it out as well. Along with a host of physiologists we've been able to tailor the programs that can help lead to performance improvements."

For any new fitness device third-party integration is going to be crucial to maximising its appeal and that was definitely a priority for the team. Hex is compatible with all Garmin Forerunner watches using ANT+ to pair and uses a colour coded system to signal to tell you whether you should be taking a break or whether there's still something left in the tank to push on. The companion app captures GPS, pace and cadence data as well and lets you export data to other platforms including Garmin's.

The idea of tapping into your oxygen may well be reserved for the elite, but Babini believes it won't be too long before people will see the value of the data and will start to form a big part of shaping fitness regimes in the same way that heart rate has done for many years.

"We were worried about how we were going to sell it and how to explain to people what it can do and why oxygen saturation is important," he said.

"This is going to be the new heart rate. If you talk to a physiologist at Nike or any other sports company they know about it and they are working on it. If you speak to someone who runs around in Hyde Park twice a week it's a lot different. No one has a device that can be bought for less than $300 that can measure the oxygen saturation. In the future I strongly believe that this will replace heart rate and I believe Garmin will build a similar solution."

Future of fitness lies away from the wrist

Humon: Measuring oxygen levels is the fitness metric everyone is going to want

Humon's first wearable is now available for pre-order and is primed to ship in June. International sales are scheduled to kick in before the end of the year as well. Babini is confident the startup is here to stay and places a big emphasis on the decision not to build a wrist-based wearable.

"Most wearables that are going to survive are going to be the ones from companies where wearables won't be worn around the wrist," he said. "There's really nothing that can be reliably measured from the wrist. There's no wrist based heart rate monitor that is accurate, they are all inaccurate. Wearables will be placed on the part of the bodies that matter."

Beyond that, the wheels are already in motion to evolve and improve the ecosystem and it's already in the process of looking at other places the monitoring tech can prove valuable.

"Our insights and artificial intelligence we are building will only get better," he said. "Because the device can be worn on any part of the body, we have received interest from professional teams from american football, basketball and soccer. The coaches want the devices on their athletes. That's a process we will start next year. We believe our sensors can really impact on how different people train and how they can get better, stronger and faster."

How we test

Michael Sawh


Michael Sawh has been covering the wearable tech industry since the very first Fitbit landed back in 2011. Previously the resident wearable tech expert at Trusted Reviews, he also marshaled the features section of

He also regularly contributed to T3 magazine when they needed someone to talk about fitness trackers, running watches, headphones, tablets, and phones.

Michael writes for GQ, Wired, Coach Mag, Metro, MSN, BBC Focus, Stuff, TechRadar and has made several appearances on the BBC Travel Show to talk all things tech. 

Michael is a lover of all things sports and fitness-tech related, clocking up over 15 marathons and has put in serious hours in the pool all in the name of testing every fitness wearable going. Expect to see him with a minimum of two wearables at any given time.

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