feel your feet and hands, and there's also an altimeter. The Trek Alpine is fairly easy to fit using the cable ties provided and it is a very user-friendly computer that can also be upgraded to display heart-rate. The choice you would have to make

at our heart-rate monitor or stopwatch," says Bill Black, who coached the GB Men's Triathlon Team at the Sydney Olympics. "But if we train at a certain pace in the pool we can keep cross-checking with the clock - plus every length is usually 25 metres

to let your heart rate return to normal and for your body to clear out any metabolic  waste created during your efforts," says Kastor.7. Don't worry if you ache a littleIf you ease into running, your post-run discomfort shouldn't be debilitating

worse for the extra miles, and having looked at my heart rate over the last few runs it does look like my fitness is improving.My speedwork sessions still feel tough – doing them outside feels totally different to using the treadmill. I had