There's nothing strange in seeing a cyclist exchanging his bike for a quick run to simply maintain fitness or for when its not possible to ride. Like in all disciplines that also use running as training to improve fitness needs a heart rate monitor to control important values such as heart rate and most of them having options to track distance, calories burnt and many more. To do this, a heart monitor on our wrist is the best solution: there are different types available on the market using the latest technology to get the most out of your potential.