Getting outside and being active during the day can have a positive impact on a child's sleep at night. In this blog, we'll take a closer look at how outdoor activity and exposure to natural light affect babies' and toddlers' sleep, and what parents can do to maximize the benefits.
The Science
Before we delve into the impact of outdoor activity, it's important to understand the concept of circadian rhythms. Your baby's circadian rhythm is a biological process that follow a roughly 24-hour cycle and influences the timing and duration of sleep. The primary cue that synchronizes the circadian rhythm is exposure to light. While indoor light can have an impact on your child's circadian rhythm, being outside exposes your child to light that is orders of magnitude brighter than anything that you could achieve inside. When babies and toddlers get outside and are exposed to natural light, it helps to regulate their circadian rhythms, which can improve their sleep quality and duration at night (for more on circadian rhythms and how sleep works check out this blog).
Some research shows that spending more time outside in bright light during the day can improve children's sleep quality and duration. The benefits to spending more time outdoors during the day include longer nighttime sleep duration and better sleep quality. Exposure to natural light shortly after waking can help maintain earlier bedtimes and longer sleep duration at night, when coupled with dimmer light in the evening before bed. Natural light is especially important for newborns. A baby's circadian rhythm stabilizes over the first few months of life. Regular exposure to natural light has also been shown to accelerate nighttime sleep consolidation (for more on newborn sleep, check out this blog).
Going outside usually increases a child's physical activity too. Physical activity has been linked to improved sleep efficiency among young children, meaning that children spend more of their time in bed asleep. Outdoor play can also improve mood, reduce stress and anxiety, and increase overall physical health, all of which can have a positive impact on sleep quality.
Although there are certainly benefits to getting your child outside, there can be some drawbacks too. Exposure to bright light at the "wrong" time of day can inhibit sleep. Make sure you are inside 1-2 hours before putting your child to bed because light in the evening suppresses melatonin production and shifts sleep onset timing later. In addition, some studies find weak or no associations between physical activity and sleep. This might be because children who are generally very active have been shown to have worse sleep outcomes. This doesn't mean that you need to prevent your child from being active. Just know that this association exists and do your best to help your child wind down in the few hours before bed. If you have a toddler or preschooler and are experiencing bedtime challenges, this blog should help.
Tips for Using This Information in Real Life
Now that we know how outdoor activity and natural light can benefit sleep in babies and toddlers, let's look at some tips for using this information in real life.
Get outside every day: Make a habit of getting outside with your child for at least a little bit every day, weather permitting. Even 20-30 minutes of outdoor time can be enough to make a difference.
Time outdoor activity appropriately: Aim to get your child outside in the morning or early afternoon to take advantage of natural light exposure. Avoid late afternoon or early evening outdoor time, as this can shift your child's circadian rhythm later and make it harder for your child to fall asleep at night. (If your child is up too early, then evening light can be helpful. Check out our blog on how to fix early waking here.)
Encourage physical activity: Encourage your child to be active outside by playing games, exploring, or engaging in other age-appropriate activities. Try to make outdoor time fun and engaging to maximize its benefits.
Maintain a consistent sleep schedule: Even with outdoor activity and exposure to natural light, maintaining a consistent sleep schedule is crucial for promoting healthy sleep in babies and toddlers. Aim to establish a consistent bedtime and wake-up time, even on weekends. If you aren't sure how much your child should be sleeping, check out this blog.
Not sure how to get into the habit of getting outside? Here are some ideas:
Take a daily walk around the block or to a nearby park. Even a short walk can provide an opportunity for fresh air and outdoor activity.
Make outdoor playtime a part of your daily routine, by bringing a play mat outside for babies or playing a game of catch or with sidewalk chalk for toddlers.
Plan a daily picnic lunch or snack in a nearby park or green space.
If possible, walk to the grocery store instead of driving or take your child to a local farmer's market or outdoor mall.
Sign up for a family-friendly outdoor class or activity, such as a gardening or nature walk program.
By incorporating outdoor time into your daily routine, you can help ensure that your child is getting enough fresh air and physical activity each day. Remember to always supervise your child during outdoor activities and follow any safety guidelines appropriate to your child's age and development.
Of course, increasing daytime outdoor time won't solve behavioral sleep issues. If your child is waking frequently, then these blogs might help (4-month sleep regression, 9-month sleep regression, toddler sleep regressions). If you need more help, Our team of sleep experts, including PhD-level sleep scientist, Dr. Erin Flynn-Evans and nurse Meg Casano, have developed a comprehensive online class on sleep training for babies aged 6-15 months. With information on setting schedules, developing routines, and reducing night feedings, our class offers four different approaches to sleep training, including options with high and low soothing. For parents who want even more personalized support, we also offer one-on-one consultations.
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