He likes to use a pulse monitor wristwatch, which has a cartoon face to tell the wearer when to put in more effort, depending on their optimal heart rate.

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Many were to do with health - from the pulse monitor you plug into your smartphone, to a fitness monitor, the Fitbug, which sets you exercise goals after monitoring your physical activity.

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Checking your heart rate, whether using a monitor or simply feeling your pulse immediately after a workout, can provide valuable information as to how hard you are working.

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Brands like Cookoo, Martian and Pebble let you read your email, monitor texts, play music and take your pulse on your wrist.

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