Ever walked into the gym, made a beeline for the rowing machines (maybe all the treadmills were taken?), plonked yourself down and then kind of... not really been sure what to do next? We hear ya! But ...

Gyms are full of fancy contraptions these days – reformers, VR games, stair machines – but don’t forget about the rowing machine in the corner (or let the Hyroxers hog it). By some calculations, ...