THE body’s natural clock influences much more than just our sleep-wake patterns and hormonal cycles. Physicists have found that circadian rhythms affect the variability of heartbeats and even the movement of limbs.
It has long been known that heart attacks and other heart-related failures occur most often in the hours around 10 am, presumably reflecting the stress of morning activity following a night of rest. But Eugene Stanley’s team from Boston University in Massachusetts discovered that circadian rhythms might also have a role to play. They studied the variability in the time between heartbeats in different people. Lower variability has…
