World's first strapless continuous heart rate monitor for athletes utilizes Bluetooth low energy wireless technology

February 21, 2013 // By Paul Buckley
The world's first strapless continuous heart rate monitor for athletes is now employing a Nordic Semiconductor µBlue nRF8001 Bluetooth low energy Connectivity IC to communicate live or stored training data directly from the wrist to any Bluetooth v4.0 enabled device.

The MIO ALPHA sports watch is designed for both serious amateur and professional athletes and employs an electro-optical cell with a pair of optical sensors on the underside of the watch to track blood flow volume in the wrist as it pulsates with the rhythm of the heart to extrapolate heart rate.     

"This technology enables the MIO ALPHA sport watch to measure a user's heart rate without an uncomfortable strap at performance speeds up to 12mph [19km/h], with the same accuracy as traditional EKG/ECG [electrocardiogram] based heart-rate straps," commented Emily Rothwell, VP of Sales and Marketing at Physical Enterprises Inc., the company behind the MIO ALPHA.     

"Achieving this level of end-user simplicity without compromising accuracy compared to a traditional heart-rate strap wasn't easy," admitted Rothwell. "An onboard motion detector and built-in noise filtration software developed by consumer electronics giant Philips compensate for arm movements and perspiration typical of fast running and cycling, which can all interfere with blood flow measurements."    

The class-leading ultra-low power and RF performance characteristics of the Nordic Semiconductor µBlue nRF8001 Bluetooth low energy Connectivity chip enable the MIO ALPHA's built-in rechargeable lithium ion battery to offer up to 10 hours of 'live' heart-rate smartphone-linked monitoring (its most energy intensive operating mode). This ensures reliable performance even in demanding 2.4 GHz operating environments such as busy, modern gyms that can house numerous local active devices and emitters (in particular Wi-Fi) all working on the same frequency.     

In operation, the MIO ALPHA can be used as a standalone device and includes features such as workout timers, continuous heart rate display and audible heart-rate zone alerts, or in conjunction with popular smartphone apps such as MapMyRun, RunKeeper and Wahoo Fitness.     

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