Setting Your Biological Clock

Light, particularly sunlight, plays a crucial role in regulating the body's internal clock, making it 1,000 to 10,000 times more effective than exercising in darkness. Melanopsin cells, discovered by David, are key to this process as they provide the only direct input to the central clock. While exercise and food intake also influence circadian rhythms, they do so through different pathways that complement the effects of light.