Exercise is deeply beneficial to sleep. And you don’t have to run marathons or scale mountains to receive those benefits. Any amount of exercise can have a positive effect on your nightly rest. A regular routine of moderate exercise – 20 to 30 minutes a day, most days of the week – can help you sleep longer and better, and can strengthen your overall sleep routine.
More exercise, more deep sleep
Exercise increases time spent in deep sleep, a phase of sleep that is essential to the body’s physical restoration and rejuvenation. During deep sleep, the body releases high levels of human growth hormone, which help repair and replenish cells throughout the body. As we age, we spend less time in deep sleep. Maintaining a regular exercise habit can help to offset this age-related decrease in deep sleep.
People who exercise tend to fall asleep more quickly and sleep more soundly. A survey conducted by the National Sleep Foundation found regular exercisers rated their sleep quality significantly higher than people who do not exercise. Exercisers also reported experiencing less difficulty falling asleep and staying asleep throughout the night. Science backs this up. Studies show exercise improves sleep onset – the time it takes to fall asleep – and experience fewer awakenings throughout the night. Physical activity during the day also may contribute to greater sleep duration, an increase the total amount of sleep you receive in a night.
Falling body temperature helps you drift off
Daily exertion of exercise makes you more tired and ready for sleep at the end of the day. Exercise also raises body temperature. A gradual drop in body temperature occurs during the later part of the day and evening, as part of the natural physiological process of preparing for sleep. Exercise can enhance this drop in body temperature, helping you to fall asleep more easily.
The broad sleep-benefits of exercise
Regular physical activity influences sleep indirectly, by improving other conditions that contribute to sleep troubles:
- Regular exercise lowers stress. Stress is a common source of sleep disturbance. Exercise can ease anxiety and aid in mental and physical relaxation, making sleep easier to achieve and sustain throughout the night.
- Exercise makes it easier to control your weight. Maintaining a healthy weight protects sleep over the course of a lifetime. People who are overweight are more likely to experience disrupted sleep and are at higher risk of certain sleep disorders.
The timing of exercise is important, both to maximize its sleep-enhancing benefits and to avoid any interference with nightly rest. Exercising in the morning boosts alertness and focus, and helps to strengthen the internal body clock that regulates sleep-wake cycles. The early-morning benefits of exercise to sleep are enhanced when physical activity is combined with exposure to natural light. Getting outside early in the day is another way to increase morning alertness, and to strengthen the body’s sleep-wake cycles, enhancing sleep at night.
Late afternoon and early evening is another excellent time for exercise. Toward the end of the day, body temperature is at its highest. Exercise raises body temperature even further, enhancing the drop in body temperature that is associated with feeling sleepy and with sleep onset. Scheduling exercise in the late afternoon can maximise these benefits to sleep. While late afternoon exercise can often be beneficial, physical activity too close to bed can interfere with sleep. To avoid disrupting sleep, it’s a good idea to finish exercising at least three hours before your bedtime.
A little bit goes a long way
You don’t have to spend a lot of time exercising to receive a boost to sleep. Nor do you need to get your daily exercise all at once. Breaking up exercise throughout the day will provide the same benefit to sleep, provided you don’t schedule exercise too close to bedtime. A 10 minute walk in the morning, at mid-day, and before dinner can achieve the same improvements to sleep as a 30-minute session at the gym.
Since all types of exercise will help sleep, you’re free to find a physical activity you like. Do yoga in the morning or take a dance class. Walk the dog or step out for a jog in the sunshine. Join a gym or your company’s softball team. The more you enjoy exercise, the more likely you are to stick with it – and the more your sleep will benefit.