Heart rate monitoring specialist Salutron has announced its latest wearable device - the LifeTrak Brite R450, offering an extra ingredient to the usual activity tracking mix.
The LifeTrak Brite R450 monitors both ambient light and blue light exposure simultaneously, and warns you when you've not had too much or too little of the latter.
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In case you're unfamiliar with the term, blue light is a high frequency light (that is emitted from LED displays); and while it's said to be beneficial to mood and energy levels, it can also cause trouble when it comes to bed time.
Sleep expert Professor Paul Gringras recently explained to Wareable that too much blue light late at night, for example looking at a smartphone display, could contribute to restlessness.
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Able to track sleep, the LifeTrak Brite R450 also boasts a vibrating alarm and Intelligent Wake Up function that determines a users's optimal wake time based on real-time sleep quality.
As well as the light and sleep functions you'll find calorie tracking, heart rate monitoring and step counting; and the companion app offers weekly and hourly view modes.
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Charging won't be an issue with the R450 - it runs on regular watch coin batteries and you should get six months of life between changes.
On sale 15 October, the Salutron LifeTrak Brite R450 will cost $129.99. The UK price is expected to be around ¬£79.
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