If you stuff yourself silly this Christmas, drink too much booze or lay around watching too many Only Fools and Horses repeats, don't worry - the Fitbit Ultra is going on sale in the UK from Boxing Day, so you'll be able to get right back into shape.

That's the plan, at least - as the US company brings its popular actvity tracker to British shores for the first time. In the US Fitbit has sold thousands of trackers since its launch in 2010, growng its business over 300 per cent in 2011.

So it seems to be fighting its corner pretty well in the face of stuff competition from the usual fitness big names such as Nike and Adidas.

The Fitbit Ultra will track your steps, distance, sleep patterns and even stairs climbed using its "state-of the-art altimeter" and boasts a display for real-time feedback. You can't cheat it when it comes to stairs either, it can tell the difference between stairs and an escalator.

The device teams up with an iPhone app and an online portal where all your data is synced and there's a community aspect too, so you can set yourself goals and inspire / be inspired by other Fitbit Ultra users.

"Our research shows us that one of the biggest challenges to maintain fitness regimes is motivation – especially as we get further into January," said Gareth Jones, VP for Fitbit.

"Fitbit offers a really simple and easy to use system that motivates as well as making it easy to share progress with interested parties, be they friends, family and/ or colleagues. The Ultra, which is the first in a number of related products we will be bringing to the UK, combines all that is best in design with technology which delivers all the information you need to track and communicate your progress and help motivate for the future."

Fitbit Ultra will be available to pre-order from 26 December at will hit shops on 2 January. It comes in blue or plum and will cost £79.99.