TomTom has integrated heart monitors into two new sportswatches, the Runner Cardio and the Multi-sport Cardio.

TomTom's sportwatches combines GPS technology with an integrated heart monitor to measure the intensity of a workout. Five intensity zones have been programmed into the Cardio sportwatches, all of which can be accessed using a practical D-Pad arrangement of buttons found on the strap.

Integrating the heart monitor eliminates the need for a separate chest strap. The Mio optical sensor found in the smartwatch works by "monitoring changes in blood flow by shining light through the skin".

TomTom's head of marketing in the Asia Pacific, Winnie Kwan, said: "Heart rate monitoring is the single most accurate way to understand how the body is responding to exercise. Now all runners can easily use heart rate training to improve their performance," said Winnie Kwan, TomTom's head of marketing in the Asia Pacific.

Samsung's second generation of Galaxy watches already come equipped with heart monitors; however, the Samsung watches don't feature in-built GPS, and must be used in conjunction with select Samsung smartphones to track exercise routes.

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TomTom's sportswatch works across a number online community platforms, including the TomTom MySports website, MapMyfitness, RunKeeper, Training Peaks and Strava.

The TomTom Cardio GPS sportswatches have a scratch resistant screen, are waterproof to 165 feet, feature Bluetooth connectivity and have a battery that can last up to 10 hours.

The Runner Cardio and the Multi-sport Cardio are available now for $349 and $399 respectively.

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