rods and cones; it contains cells that then report to the suprachiasmatic nuclei in the hypothalamus.” This part of the brain controls our circadian rhythms over a 24-hour cycle. “It’s the light that controls it. It’s like saying: 'Why can’t you control your heartbeat?'” But it isn’t just students who would benefit from a later start. Kelley says the working day should be more forgiving of our natural rhythms. Describing the average sleep loss per night for different age groups, he says: “Between 14 and 24, it’s more than two hours. For people aged between 24 and about 30 or 35, it’s about an hour and a half. That can continue up until you’re about 55 when it’s in balance again. The 10-year-old and 55-year-old wake and sleep naturally at the same time.” This might be why, he adds, the traditional nine to five is so ingrained; it is maintained by bosses, many of them in their mid-50s and upwards because “it is best for them”. So, should workplaces have staggered starting times, too? Should those in their 50s and above come in at 8am, while those in their 30s start at 10am and the teenage intern or apprentice be encouraged to turn up at 11am? Kelley says that synchronized hours could have “many positive consequences. The positive side of this is people’s performance, mood and health will improve. It’s very uplifting in a way because it’s a