If you are looking to settle down for a long Winter's nap, you should look into adding some exercise into your life. eDiets thinks doing cardio between 4 and 6 p.m. might just help you snooze more deeply. Circadian rhythms that affect our sleep and wake cycle are heat sensitive. When you exercise you increase your body temperature, which is the opposite of what your body does when sleeping. By raising your temperature before dinner, your body will experience a steeper drop in temperature by bed time. This more dramatic temperature change might just help escort you to the land of nod more quickly and help you stay there.