When Runner's World readers were asked to list their essential kit last year, heart-rate monitors came out on top. Unfortunately for the female runner, using a heart-rate monitor is usually an uncomfortable experience, requiring 10 minutes before

Gone are the days when runners would rate our efforts based on the colour of their cheeks after a run. Heart-rate monitors are now so easy to use, affordable and accurate that there's no excuse for skipping the science bit in your training. Most

Heart-rate monitors vary hugely in price and functionality. For less than £20 you can pick up an HRM that simply measures your pulse, while parting with £150+ will give you a monitor that will set training zones for you, tell you how many calories

though, it does the basics well enough.Contact www.timex.comTimex BodyLink Trail Runner £180 Tested by Big KevFeatures Simultaneous display of heart rate and speed distance, 2 linked interval timers, latitude, longitude and altitude, navigation

, but your new training paces might come as a surprise too. Before you get started, work out the right benchmarks to work towards by finding your maximum heart rate. If you're a complete beginner, start off with this very approximate formula: 214 - (0.8 x

’s still packed with all the features that made the 305 great: it monitors your time spent running, distance, pace, calories and heart rate, and your runs can be stored in the memory, so you can review and analyse the data and the routes you’ve taken later

If you are new to running, or only want an approximation of your maximum heart ate, you can use the formula of 214 – (0.8 x age) for men and 209 – (0.9 x age) for women. Unfortunately for 5-10 per cent of the population, this figure can be wrong

11 heart rate monitorPantsAnts, for his excellent assessment of his Polar 625x speed & distance monitorCMR, for his love-hate review of his Garmin Forerunner 201David Howard, for his review of his Navman R300And, as we also promised a 205 or 305 to a

watches on test is its heart rate monitoring functions. There's just the one hear-rate zone compared with the Polar's five, and there are no features like Polar's OwnIndex V02 test.Contact www.nike.com; 0870 700 0988Suunto T6 - £310 (£250 without the foot

(with a battery-life reading in hours), a PC interface to download data (with free Garmin software) and the GPS lock, once established, is reliable. Contact www.garmin.com; 0870 850 1241Timex Speed and Distance Monitor – £180Timex’s arm-mounted receiver