Getting an extra hour of sleep isn’t necessarily impactful unless it’s the right kind of sleep that truly restores your body and mind. There was a time when I eagerly anticipated the clocks springing forward, especially when it coincided with a bank holiday Monday, promising the luxury of an extended lie-in. I would diligently ensure my alarm was switched off the night before, eagerly anticipating a morning of uninterrupted rest. I’d linger under the covers, postponing any plans until well into the afternoon, waiting until I felt sufficiently rejuvenated to emerge from my slumber.
However, my perspective on sleep shifted when I started using a sleep tracker. Despite clocking in a seemingly solid eight hours of sleep each night, I discovered that I was falling short on one crucial aspect: deep sleep. According to the data, I was only experiencing anywhere between 6-12 percent of deep sleep, averaging about one hour and seventeen minutes, whereas the recommended range by The Sleep Foundation is 20-25 percent, equivalent to 1.4-2 hours.
Deep sleep is widely regarded as the most rejuvenating phase for the brain, during which the body effectively purges potentially harmful substances from its system. A recent study published in the journal JAMA Neurology underscored the importance of deep sleep, revealing its significant impact on cognitive health. Conducted by researchers from the Monash School of Psychological Sciences and the Turner Institute for Brain and Mental Health in Melbourne, Australia, the study suggested that insufficient deep sleep could heighten the risk of developing dementia. As someone who harbors a profound fear of cognitive decline, this revelation prompted me to seek assistance from a sleep expert in hopes of resolving my deep sleep deficiency.
Sleep stages explained
Understanding the different stages of sleep is crucial to comprehending its importance in our overall health and well-being.
During deep sleep, also known as slow wave sleep (SWS) or stage 3 sleep, the body engages in vital physiological processes essential for both physical and mental restoration. Growth hormones are released during this phase, promoting tissue repair, muscle growth, and immune system renewal. Moreover, the brain actively clears out toxins accumulated during waking hours. A deficiency in deep sleep has been linked to mood disturbances, compromised immunity, and an elevated risk of chronic conditions such as dementia.
«If you’re fortunate, you’ll transition into stage 3 deep sleep,» explains Bostock. During this phase, the brain undergoes rhythmic pulsations, facilitating increased circulation of cerebrospinal fluid and the release of toxins. Approximately 95 percent of growth hormones are produced during deep sleep, crucial for mood regulation and cognitive function. Bostock emphasizes that deep sleep is profoundly restorative, with a higher occurrence typically observed in the first half of the night.
In the latter part of the night, the sleep cycle shifts to include more REM (rapid eye movement) sleep, characterized by heightened brain activity resembling wakefulness. REM sleep is particularly conducive to innovation, creativity, and emotional regulation. Each sleep cycle repeats approximately every 90 minutes.
Contrary to common belief, Bostock highlights that it’s natural to awaken between sleep stages, as our ancestors evolved to do so as a safety mechanism. Although some may perceive this as disruptive, especially as they age and experience more frequent awakenings, it’s a normal aspect of sleep architecture. Therefore, individuals shouldn’t become overly distressed if they awaken during the night.
The sleep scientist weighs in
The sleep scientist, Bostock, offered valuable insights to guide my approach. Rather than fixating on my sleep tracker’s data, she encouraged me to pay closer attention to how I felt each day, serving as my deep sleep coach for the duration of the experiment.
Bostock highlighted that while sleep trackers offer some utility, their accuracy varies widely, typically ranging from 50-60 percent when comparing sleep stages. However, becoming excessively preoccupied with sleep metrics can exacerbate insomnia, a phenomenon known as orthosomnia.
Following Bostock’s advice, I embarked on a trial to improve my deep sleep, incorporating a simple daily log to record my subjective feelings alongside my tracker data.
Addressing my rigid beliefs about sleep duration, Bostock challenged me to experiment with shorter sleep periods and assess how I felt the following day. Despite currently experiencing 6-17 percent deep sleep, Bostock assured me that adult norms typically range from 15-25 percent, indicating that my current situation wasn’t a failure but rather an opportunity for improvement.
By adopting Bostock’s recommendations and maintaining a flexible mindset towards sleep, I aimed to explore strategies to enhance my deep sleep quality.
My deep sleep experiment
“If light sleep wasn’t useful you wouldn’t spend half of your night in stage 2 sleep,” says Bostock. “Light sleep is still having an impact on your health. But it’s possible to do small things to impact the amount of deep sleep you get, though the changes will be subtle, small and probably slow but every bit counts,” says Bostock. “If we can try and get you a little bit more deep sleep each night, over time that will impact how you feel.”
Sleep hygiene advice tells us to sleep in a dark room, drink herbal tea before bed, have a hot bath and if we wake up in the middle of the night, get up and do something else, like the ironing, until we feel tired. I had read advice like that so many times, it seemed more tired than I was. I hate ironing. So Bostock and I decided on making five key changes that she felt would be most impactful for my deep sleep but that I felt were easy enough that I’d actually do them.
What the numbers said
The results were a surprise as I slept a little less but my deep sleep improved by 2 per cent. I also felt much better.
Maintaining a regular sleep schedule, even on weekends, is crucial for syncing up your body’s internal clock and optimizing sleep quality. Drifting off to sleep and waking up at consistent times helps regulate circadian rhythms, ensuring that your body operates on the same time zone every day. While it may be tempting to indulge in long lie-ins on weekends, doing so can disrupt your sleep patterns and lead to what experts call social jet lag.
Don’t snooze
The detrimental effects of hitting the snooze button became apparent during my sleep experiment. Pressing snooze not only prolongs sleep inertia, that groggy feeling upon waking up, but it also makes it harder to wake up feeling refreshed. Research published in the Journal of Physiological Anthropology in 2022 found that pressing snooze can extend sleep inertia for up to 20 minutes, further disrupting the wake-up process. Therefore, it’s advisable to avoid hitting snooze altogether and instead aim to wake up at the same time every day, even on weekends. This consistency will help regulate your body’s sleep-wake cycle and promote better overall sleep quality.
Exercise
Exercise plays a crucial role in regulating sleep patterns and improving sleep quality. As explained by Bostock, physical activity helps burn adenosine triphosphate (ATP), a fuel that produces adenosine, a substance that promotes sleep pressure. By engaging in regular exercise, you increase the desire to sleep naturally, making it easier to fall asleep and stay asleep throughout the night.
Wake up to light
Exposing yourself to bright light in the morning is another effective way to enhance your sleep-wake cycle. Bright light stimulates receptors in the back of the eye, signaling the brain’s master clock to promote alertness and wakefulness. Simply switching on the lights in your bedroom upon waking can help kickstart this process and set a positive tone for the day.
Avoid caffeine after midday (or give it up)
Cutting back on caffeine consumption, especially after midday, can have a significant impact on sleep quality. Caffeine temporarily blocks adenosine receptors in the brain, preventing feelings of sleepiness. By avoiding caffeine later in the day, you allow your body to naturally build up sleep pressure, making it easier to fall asleep when bedtime arrives.
How do I feel afterwards?
After implementing these changes for 20 days, the results were promising. Despite the initial challenges of adjusting to a regular sleep schedule and cutting back on caffeine, there were noticeable improvements in focus, alertness, and overall energy levels throughout the day. The gnawing tiredness experienced in the evenings indicated that sleep pressure was being effectively built up, leading to better sleep at night.
While it may be tempting to sleep in on weekends, maintaining consistency in waking and sleeping times proved beneficial for overall sleep quality and daytime functioning. The commitment to sticking with these changes, despite occasional challenges, yielded positive results and contributed to improved mood and mental well-being.
For those struggling with sleep issues, trying these simple lifestyle changes may offer significant benefits without the need for drastic measures. By prioritizing sleep hygiene and making small adjustments to daily habits, you can optimize your sleep and reap the rewards of better rest.