Nike FuelBand prototype and design process detailed in pics

Nike's lifted the veil on how its fitness-tracking FuelBand gadget came to be, also showing off a prototype design for the motivational wrist-occupier.

Development kicked off in late 2009, Nike says, with colour-coding to demonstrate how much exercise you'd done proving a popular idea from the off. The team was inspired by "thick, terry wristbands worn by the tennis greats of the '70s", apparently, and wanted a band covered in smart panels that would change colour "like a chameleon".

That obviously proved too difficult, as the FuelBand sitting in shops today looking nothing like the wrist-lizard Nike was dreaming of. The NikeFuel metric for exercise, however, was key to the gadget's development.

NikeFuel is the made-up substance that FuelBand wearers acquire when they exercise, watching as a grid of coloured lights charts your progress through the day from red to green.

Happily the FuelBand doesn't need to be told when you're exercising, which means you get credit for ordinary tasks like hoofing it up several flights of stairs, or gambolling clumsily towards the bus before it pulls it away.

The fictional fuel, Nike explains, is a modified version of Metabolic Equivalent of Task (MET), which defines how much energy you're expending based on how much oxygen you're using, and combined with the wristband's built-in accelerometers.

The final band itself, meanwhile, conceals two curved batteries, while the polymer coating on the outside is heated to melting point.

Are you a FuelBand fan? Do you think it works well, or are there aspects you would change? Let me know in the comments, or on our Facebook wall.

Image credit: Nike