A facebook friend recently wrote, ‘…Nearly cried when I realised I didn’t have my Garmin' when she turned up at a half marathon, and I sympathised. Like its predecessor, it’s easy to use and provides excellent training feedback. And in the recent Brighton Half Marathon long course controversy, it was feedback from this that forced organisers to publically acknowledge that they’d made a mistake and adjust everyone’s times accordingly.

Just over five years ago many of us would have taken to our car to measure how far we’d run, and estimates about pace and distance and weekly mileage would be just guesses!

Until recently there were two main types of speed and distance monitors for runners: GPS-based models which use satellites to track your movements; and models that use foot-pods on your shoelaces which you preset according your individual stride and measure your speed and the distance covered.

But now there are apps for iphones and android devices which come with pods, and bands, that link up to satellites to measure time over distance almost as effectively as the watches, most notably Nike+ and micoach from Adidas. And another recent development has been the arrival of sophisticated online training programmes and support packages, where you can not just record your data but share it with other users (eg www.garminconnect.com).

And as well as recording time over distance, most now also measure heart rate, so you have as much data as a sports scientist need to accurately plan your training and assess your progress in races.

Need to know

In the last three to five years this market has exploded. Garmin Forerunner are the market leaders and the Forerunner series offers a wide range of gadgets with different levels of sophistication. The key change over recent years has been that these gadgets are now sleeker (you no longer need to look like you’re wearing a laptop on your arm), easier to use (you don’t need to be a complete geek to work out how to use them) and the accuracy and ability to pick up satellite reception has improved so that you can often get a good signal even in built up areas.

Timex tend to offer more functions than Garmin and the Ironman series (not surprising given the name) is very popular with Triathletes. Garmin Forerunners are doted on by runners. Polar the original heart rate monitor makers cross over to cyclists, runners, triathletes, and Suunto, make GPS watches with features such as compass making them popular with mountaineers, mountain runners, and trail runners.

Extras that make these watches ‘must-haves’ include functions that mean you can plan accurate interval sessions, virtual personal trainers and target pace/heart rate alerts. Most allow you to measure the elevation and altitude, as well as providing detailed online maps where you can see the course you’ve just run.