Get ready in five minutes Nothing sums up modern life better than the name of a current Japanese TV game show: Get up, have breakfast and get ready for work in five minutes.The new fad is for HIIT - short for High-Intensity Interval Training whereby just twelve minutes of very intense activity is supposed to be 3 every bit as beneficial as conventional exercise.It's supposed to get you fitter in a considerably shorter period of time than conventional exercise routines.Not only are activities getting significantly quicker, but our assumptions are changing, too.Advocates of HIIT training claim that it can burn fat up to 450% more effectively than low-intensity exercise.They also maintain that it speeds up metabolism and so makes you burn more calories throughout the day.A recent survey suggests we now walk 10% faster than we did ten years ago.But have our personalities changed, too?