AmpStrip CEO: 'Everyone knows that optical heart rate sensors are not accurate'

Heart rate sensing band aid creator on wearables versus invisibles
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"We were way before Fitbit," Dave Monahan, CEO of Fitlinxx told Wareable from his office in Philadelphia. He's talking to us on the phone, but the words are spoken with an audible smile.

"We had wearable devices in the market in 1999. Our first fitness wearable was the FS1. It clipped to your running shoes and sent data wirelessly to a watch, and when you were running you could watch pace, distance and calories on the watch – and that was in 1999!

Read more: Future fitness tech round-up

"When we started back in the 90s we had to tell people what 'wearable' actually meant!"

It was fair to say the FS1 was ahead of its time. It didn't change the world, despite being a forerunner to the wearables we know and love today.

Now 16 years later Fitlinxx is back again with AmpStrip – a connected band aid that will continuously monitor your vitals for up to seven days at a time. However, since the FS1 the company has produced Nike+ and a host of high-end gym equipment.

AmpStrip CEO: 'Everyone knows that optical heart rate sensors are not accurate'

However, Monahan was always certain that wearables were the future.

Monahan, started life working on drones for the US Defence industry way before they were as popular as today, worked for Microsoft before making the switch to the health and fitness market.

"I had a passion for engineering and fitness. Fitlinxx used to be a company focused on close systems for fitness, taking data from cardio and strength equipment, and showing it to members of a fitness facility, enabling them to create goals. It's still a big business for us," he said.

"The Nike+ product is actually our product, and we always had a pedigree in fitness and sports and that kind of brings us up to the AmpStrip, which is a product we think is needed in the sports market.

AmpStrip CEO: 'Everyone knows that optical heart rate sensors are not accurate'

"After I joined Fitlinxx my thought was that everything was heading towards wearable or fitness devices. We ended up acquiring FitSense a year after I joined, and incorporated their technology for wearable fitness devices," he continued.

"My feeling was that across all technologies, things always go personal. So we looked at what was around, and all fitness and healthcare devices were large, and people wanted to take them home and use them.

"I'm surprised it's taken so long. We were way ahead of market adoption."

Back in 1999 Monahan has a unique product, and he seems to have gone full circle.

AmpStrip works by sticking to the body, and transmitting a host of biometric information back to the user's smartphone. It's designed for athletes and those with serious heart conditions, but requires users to buy new sticking plasters. A year's supply costs about $80.

But are they too far ahead of the curve again?

"Hopefully, we're not too far ahead like last time, and consumers are ready to use the product. We have done a lot of research into what the market wants, and they want 24/7 insights into their bodies as they work out and recover. Our goal was to make something easy to use and was accurate," he continued.

"The wrist is not a great place to take heart rate data"

AmpStrip CEO: 'Everyone knows that optical heart rate sensors are not accurate'

Heart rate tech has been one of the big stories of the last 12 months, with the Apple Watch, Fitbit Charge HR, Jawbone UP3 and Basis Peak all packing optical sensors. Last month, we spoke to Mio boss Liz Dickinson who said those players were lagging in accuracy.

However, Monahan believes that the wrist is flawed for heart rate tracking altogether.

"We're more accurate. I think everyone knows that optical wristbands are not accurate. They lose a lot of your heartbeats – on average 30% – which has a major impact on accuracy.

"The wrist is just not a great place to take heart rate data from."

It's not just optical wrist monitors that Monahan has beef with.

"Straps lose a lot of information, when you sweat and when the product moves. Plus, they're very uncomfortable. We have the accuracy and the comfort for 24/7 wear," he said.

AmpStrip CEO: 'Everyone knows that optical heart rate sensors are not accurate'

"As you work out you'll be getting instantaneous heart rate and heart rate zones, in real time, and uniquely, it will survive the most rigorous exercise you can put it through. Most straps and bands will not be accurate at a hard rate of exercise. We have tested it on someone swimming in the ocean for two hours a day."

Aside from tracking, Monahan says that it's what AmpStrip does behind the scenes, when you're not in training, that's just as important.

"The best time to take resting heart rate is right before you get up, while you're away. In the background we have algorithms that see you stir, know you're awake but haven't got up yet, and take your resting heart rate," he said.

The wearable disappearing

AmpStrip CEO: 'Everyone knows that optical heart rate sensors are not accurate'

Out at SXSW this year, where we met Dave's team for the first time, a lot of the talk was about wearables disappearing. And Monahan believes this is the way forward.

"We like the term invisibles versus wearables. We're behind the idea that people don't want to show off their wearable. In my opinion invisible is the right way to go. Put it into the background and forget about it. Ensure that the data can be shown off on social media, but people don't have to show it off."


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James Stables


James is the co-founder of Wareable, and he has been a technology journalist for 15 years.

He started his career at Future Publishing, James became the features editor of T3 Magazine and and was a regular contributor to TechRadar – before leaving Future Publishing to found Wareable in 2014.

James has been at the helm of Wareable since 2014 and has become one of the leading experts in wearable technologies globally. He has reviewed, tested, and covered pretty much every wearable on the market, and is passionate about the evolving industry, and wearables helping people achieve healthier and happier lives.

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