Most compendiums of studies and exercises suffer the same fate as the infamous home-trainers: one sets out full of good intentions but after a few weeks of blood, sweat and tears they are left to gather dust in a corner. Why? Any athlete prefers a proper cross-country run to a stint on the treadmill. If there is variety and a chance to make decisions, all the senses become involved. May this set of studies be spared the fate of the exercise-machine; rather they should serve as the equivalent of ...