Garmin Forerunner 35
£169.99, garmin.com
Checking resting HR over time is the best way to detect fatigue, overtraining or a depressed immune system. So wrist-based heart-rate (HR) monitors are exceedingly handy. But while chest-strap sensors are still more accurate, attaching that tight band under your bra first thing in the morning isn’t everyone’s favoured pre-caffeine activity. The main appeal of the 35 is that, as well as GPS, it records wrist-based HR data constantly – if a little erratically - something the dead-fancy watches don’t do yet.