If you're making healthy lifestyle choices but still feeling tired throughout the day, you could be disrupting your body's circadian rhythm.
What is a circadian rhythm?
All living organisms have what scientists call a 'circadian rhythm' which is an internal body clock encoded within our cells. This circadian rhythm is what regulates our body's metabolism and is what causes our body to sleep or feel awake at particular times of day. While healthy lifestyle habits such as regular exercise are important in maintaining sleep health, some of these habits can actually be detrimental to your sleep health. Here are three healthy habits that could be messing up your internal body clock:
1. Exercising too early or too late in the day
Regular exercise is great for your overall sleep health. Exercise regulates your metabolism and helps set your circadian rhythm but it also has the effect of releasing 'wakeful hormones' such as endorphins. Research led by Christopher Colwell, a professor of psychiatry at the University of California, suggests that exercise does affect our circadian rhythm, and the effect may be most beneficial if the exercise is undertaken midday. Research also suggests that exercising too early in the day can disrupt your sleep pattern and cause fatigue—particularly if you didn't have a restful sleep the previous night.
2. Planning your meals around your exercise regime
Most people prefer to forego their usual meal-time to squeeze in a workout session, but research suggests that planning your meals around your exercise regime can throw your internal body clock off-balance. A recent study by UT Southwestern Medical Centre found that mice who were given regular eating schedules slept normally at night, while mice who were fed irregularly were more active when they were meant to be sleeping.
Similar results were echoed in a 2017 study of a group of young men who experienced disruptions to their sleep patterns due to irregular eating schedules. Moreover, eating at the wrong time of day can have a significant impact on body weight and our circadian rhythm. According to Dr. Joseph S. Takashashi, Chairman of Neuroscience at UT South Western Medical Centre, for those who are trying to lose weight, dieting will only be effective if calories are consumed during the daytime when you are awake and active. Eating at the wrong time, such as late at night, will not lead to weight loss even when dieting.
3. Catching up on sleep on the weekend
In 2016, Norwegian and Swedish sleep researchers at Karolinska Institute found that sleep rhythms need to be maintained throughout the week—even on weekends. Your internal body clock thrives on regularity and even minor disruptions to your normal sleep patterns can cause tiredness and a feeling of jet-lag. The study echoed similar findings to an Australian study in 2008 that found catching up on sleep on the weekend could actually be detrimental to your circadian rhythm and could lead to greater daytime fatigue and a decline in mood and cognitive functioning.
According to science, the best way to develop and maintain your overall well-being and maximise the results of your healthy habits is to prioritise your sleep health. Read our top tips on how to develop a healthy bedtime routine here.