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Your body has a 24-hour internal clock that controls your sleep-wake cycle. If you have trouble falling asleep or waking up, it may need resetting. Join us as we explore how to reset your sleep schedule.
6 Min Read | By Chris Clark
Last Modified 5 September 2024 First Added 8 June 2022
Your body clock, also known as your circadian rhythm, can be hampered by many things, whether that be daylight savings, consuming too much caffeine, or neglecting regular exercise. Whether you’re an early riser, or a night owl, it’s important you reset your body clock when you’re struggling with sleep. So, join us as we explore how to do exactly that.
For the majority of human history, circadian rhythms were largely aligned with sunrise and sunset. However, the blue light – which has the strongest impact on the circadian system – that comes from electronic devices used at night tricks your body into thinking it’s daytime. That’s because it suppresses melatonin production, the hormone responsible for sleep regulation.
Try turning off your TV, phone, and tablet, and dim the lights at least an hour before bed to reduce your exposure to blue light levels in particular to simulate the natural progression into darkness to align your sleep cycle.
Various studies have shown that napping can improve vigilance, logical reasoning, and alertness. And this is why we sometimes feel the need to nap, to reduce drowsiness and feel refreshed.
However, waking up from long naps can lead to sleep inertia, a state of impaired cognitive performance immediately after waking up. A 2014 study found that those who are self-reported as frequent, long, and late nappers may have a higher risk of poor night-time sleep quality.
In general, healthy adults should ideally nap for approximately 10 to 20 min to enjoy the benefits of revival without compromising their body clock.
People who are ‘tired but wired’ are characterised by the inability to get to sleep despite being tired. If this happens regularly, you may begin to associate your bed with the inability to sleep, further preventing you from sleeping.
Richard Bootzin, mastermind of stimulus control, cognitive behavioural therapy for insomnia, recommends only going to bed when sleepy. If you can’t sleep within 20 minutes of trying, reduce negative bedtime associations by going to a different room and engaging in a non-stimulating activity e.g. reading a boring book.
A regular bedtime schedule can strengthen your circadian rhythm, and is beneficial for achieving good quality sleep. Since your body clock works in a series of rhythms, you need an ‘anchor time’ to start the day.
Set an alarm and stick to that time. After 2 or 3 weeks, your body should find it natural to wake at your desired time. Even a one-night alteration to a sleep schedule can induce difficulties with sleep initiation and maintenance.
Whilst most attention is directed at how much sleep you need, new research also points to the need for adults to have consistent sleep routines, with sleep irregularity being associated with greater health problems.
Caffeine is a natural stimulant and promotes both alertness and attentional performance. More importantly for sleep, however, caffeine blocks adenosine receptors – a chemical that prevents arousal, therefore, promoting sleepiness.
Caffeine prevents the build-up of adenosine, causing us to remain alert. A study found that caffeine delays our circadian rhythm by as much as 40 minutes.
A further study also found that caffeine affected sleep for up to 6 hours after consumption. And this is why we recommend cutting down your daily intake and, try to avoid a cup of coffee at least 4-6 hours before sleep.
A study found that in as little as four weeks, those with chronic insomnia could fall asleep 13 minutes faster with regular exercise. Exercise is a strong signal for the circadian clock.
Research from Arizona State University found that exercise in the morning, around 7 a.m. or early afternoon between 1-4 p.m. advanced the body clock and helped participants feel ready to start the day earlier. Those who exercised later in the evening struggled to get to sleep and were drowsier the next day.
Regardless of the time, however, exercise has a plethora of benefits and the best time for exercise is whenever you have free time to spare.
Sleep routines are ever so important, here’s one of our favourite bedtime routines to help reset your body clock:
These steps will help you reset your body clock to the right time, resulting in your having more energy, becoming more productive and leading a healthy lifestyle.
Our body clocks do shift as we age although this happens very gradually. This is therefore not an explicable factor as to why your body clock may be out of sync.
In line with anecdotal evidence, it has been found that circadian rhythms do shift across our lifespan and are latest in adolescence. Hence, whilst teenagers may have late bedtimes and even later lie-ins, the science shows that this is a naturally occurring consequence of later circadian rhythms.
Over time, circadian rhythms gradually change as we age. From middle age, they shift 30 minutes earlier every decade. Whilst there is significant evidence that shows as we get older we tend to both sleep and wake up earlier, we don’t exactly know why.
One theory is that as we age, our genes change the way our internal rhythms work, making them less reliable. Further research also posits that circadian output from the suprachiasmatic nucleus (SCN) of the hypothalamus, the central biological clock, decreases with age. This can lead to less melatonin produced at night, a hormone which peaks during sleep and result in age-related declines in behavioural rhythmicity. If you’re struggling with age-related changes in circadian rhythm, follow the advice as outlined above.
The symptoms for understanding whether your body clock is out of kilter are relatively straightforward:
If you have ever been jet-lagged before, then this is exactly what an out of sync body clock feels like. Jet lag is simply a mismatch of the time of day and your body clock and is one of the primary causes of an out of time sleep-wake rhythm.
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