An NCBI study states that “when people are exposed to sunlight or very bright artificial light in the morning, their nocturnal melatonin production occurs sooner, and they enter into sleep more easily at night. The melatonin rhythm phase advancement caused by exposure to bright morning light has been effective against insomnia, premenstrual syndrome, and seasonal affective disorder (SAD).” Similarly, an article in the Scientific American tested the impact of natural light on a persons sleep habits when being compared to primarily artificial light sources. They stated that “after the week’s study indoors, the Colorado subjects went camping in the Rockies. Instead of artificial lighting, they had only sunshine during the day and campfires at night. Wright estimates the light from the sun was four times as intense as what they experienced indoors. The nature of the light also changed during the day. Think of the bright white light of midday and the golden glow that often precedes sunset. After their week of camping, researchers measured the subjects’ melatonin levels again. The researchers found that the onset of melatonin shifted two hours earlier, and the subjects’ actual sleep shifted more than an hour earlier. Their bodies were recalibrating themselves, Wright explained.”
In addition to the positive effects of sunlight on sleep patterns, exercise in general is proven to help you fall and stay asleep better. The Sleep Foundation states that “A nationally representative sample of more than 2,600 men and women, ages 18-85, found that 150 minutes of moderate to vigorous activity a week, which is the national guideline, provided a 65 percent improvement in sleep quality. People also said they felt less sleepy during the day, compared to those with less physical activity.” From experience I can attest to the positive effect of exercise on sleep patterns. On days when I exercise, I feel like I have exerted enough energy to rest with a fatigued body and a calm mind.
If you want to check more check out these links below: http://www.scientificamerican.com/article/trouble-sleeping-go-campi/ http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2290997/ https://sleepfoundation.org/sleep-news/study-physical-activity-impacts-overall-quality-sleep