Latest news with #circadianRhythm
Forbes
24-05-2025
- Health
- Forbes
Best Time To Work: Align Tasks With Your Circadian Rhythm
Shot of a young businessman taking a break at his desk Have you ever wondered why some parts of the day feel easier than others? Why does your mind function best in the morning, yet reading an email after lunch can feel overwhelming? The answer lies in your circadian rhythm—your body's internal clock that regulates energy levels, alertness, and cognitive performance throughout the day. Just as your energy levels fluctuate throughout the day, different activities require different types of energy. The key is to find the best time to work on each activity. In my book Timebox, I explore how aligning your schedule with your natural rhythm isn't just beneficial for your health—it's a game-changer for your productivity and well-being. Let's examine the best times of day for various types of work based on how your brain and body actually operate. Your brain is sharpest in the morning, especially during the first few hours after waking up. This is your Power Time, ideal for tasks that require deep focus, strategic thinking, and willpower—like planning, writing, decision-making, and studying. Use these early hours to work on your most important goals—not email. Your willpower is at its maximum, so use this time to tackle tasks that require a lot of self-discipline. You perform at your best physically either early in the morning, when your mind is sharp, or in the late afternoon before dinner, when your body feels warm and flexible. Schedule your workout for the early morning, ideally between 5 and 7am, or around 5 to 7pm before dinner. If you are in a super busy schedule and dedicating aa full hour to a workout seems out of reach, research from Google and Fitbit shows that keeping your body active even for 10–15 minutes of distributed activity can combat fatigue, increase energy, and enhance focus. After lunch, you may notice a dip in your energy levels and cognitive sharpness. This period is perfect for handling routine or administrative tasks that require less mental exertion, like replying to emails, arranging meetings, or updating documents. Consider this as your body's 'maintenance mode.' As the day progresses, your brain grows more divergent and creative. When you begin to feel a bit tired, you tend to restrain your thoughts less, which boosts brainstorming, content generation, and innovative thinking. Use late afternoon to do more creative work or uncover the blockers you found in the morning. After dinner your brain begins to slow once more. Your willpower reaches its lowest ebb. This offers an excellent opportunity to absorb content instead of creating it. Consider reading a book, listening to a podcast, reflecting on your day, or journaling your thoughts. The best time to schedule One-on-Ones is mid-morning (9:30–11:00 a.m.), when energy remains high and individuals have had a chance to settle in. Such meetings tend to be more focused, productive, and emotionally connected. The best time for Team Meetings is Late morning (10:00–12:00) or early afternoon (1:00–3:00 p.m.). If the aim is high attendance, YouCanBookMe's research suggests that the best time and day is around 2:30 on a Tuesday. Calendly research shows that Wednesday was the most popular day for work meetings, while Tuesday was the most popular day for virtual meetings. If you engage in training or competition twice weekly, plan those sessions for the morning when you feel most alert. Use the remaining three mornings for your most critical tasks. This schedule allows you to maximize both your physical energy and mental clarity while avoiding burnout. I've observed that my optimal performance in sports occurs between 8 and 10 AM, and I cannot train too early or without having breakfast. Therefore, I dedicate three mornings to focused work and two mornings to intense exercise. Time management isn't just about discipline—it's about working with your biology, not against it. By respecting your circadian rhythm and finding the best time to work on each activity, you'll reduce stress, avoid burnout, and accomplish more with less effort.
Yahoo
24-05-2025
- Health
- Yahoo
Why You Wake Up Earlier As You Get Older
There are many jokes that center around older adults waking up before the sun, and even more about teenagers' late-sleeping habits. Turns out there's truth to them: The time our body naturally goes to sleep and wakes up is not only part of our genetics, but part of the natural aging process, too. As we age, our bodies change both internally and externally, which is a major factor behind the sleep changes that come later in life. 'Like most of the things that change with age, there's not just one reason, and they are all interconnected,' said Cindy Lustig, a professor of psychology at the University of Michigan. We asked Lustig and other experts to break down the main reasons why this occurs, and what you can do to push back if you just want those few extra hours of Zzzs. Like other aspects of our physical and mental health, the brain becomes less responsive as we age. 'The wiring of the brain is likely not sensing ... and responding to the inputs as well as it should because it's an aging brain,' said Dr. Sairam Parthasarathy, the director of the Center for Sleep and Circadian Sciences at the University of Arizona Health Sciences. These inputs include sunset, sunlight, meals, social cues and physical activity that help mark where we are in a day. 'These are all what we call time givers, or they give time to the brain,' he said. In other words, they help the brain sense where it is in the 24-hour circadian cycle. So, for a younger person, dinner time may help the brain understand that bedtime is in a few hours; for someone older, this connection may not happen. The nerves that are supposed to give the brain time cues have undergone the same amount of degeneration as the brain, Parthasarathy said. This inability to sense time cues is part of the reason why older people tend to get tired before their children or grandchildren. And, as a result, wake up fully rested and earlier than the rest of the world. 'Interestingly, one of [the reasons] seems to be that the vision changes that come with age reduce the intensity of the degree of light stimulation that our brain receives, which plays an important role in 'setting' our circadian clock and keeping it on track,' Lustig said. Parthasarathy explained that this is especially true for people with cataracts, a common eye condition that impacts more than 50% of Americans ages 80 and up, according to the National Institutes of Health. Cataracts cause blurred vision, double vision and general trouble seeing. 'If there's cataracts, the evening light doesn't go into the eyes as much, so, according to the brain, sunset is earlier than when it actually set,' Parthasarathy said. Why does this matter? Since there is less light getting into the eyes because of the vision issues cataracts cause, the body starts to release melatonin (the sleep hormone) earlier than it should. For younger people, melatonin 'starts rising after sunset,' Parthasarathy said, which is why you generally feel tired a few hours after. For people with cataracts whose brain thinks sunset was earlier, their perceived sunset is earlier, which makes them tired sooner in the evening. And going to bed sooner means waking up earlier. 'There is some evidence that cataract removal surgery can help improve sleep quality and duration by helping those light cues get through,' Lustig said. According to Parthasarathy, if you struggle with this issue, you should ignore the advice to put away the screens and instead expose yourself to bright light in the late evening. This can mean going for a walk outside before the sun sets, reading a book on a bright iPad, getting artificial lights for your home or watching TV on a bright screen. These bright lights will tell the brain that the sun hasn't set yet, which will hold the melatonin production, he said. To help yourself stay up a little later (and sleep a little later as a result), Parthasarathy said you should try these things 30 to 60 minutes before sunset, which will vary depending on the time of year and where you live in the U.S. The exact amount of time you should expose yourself to bright light varies, and might take a bit of trial and error, but he said you should aim for about two hours of exposure — and should certainly keep the light on after sunset. Lustig added you should avoid alcohol before bed — 'while that nightcap might make you sleepy, it actually disrupts the quality of your sleep.' Additionally, she said exercise can help you get better sleep and the morning sun can help your circadian clock follow the sun's rise and set cues. All in all, changes in sleep patterns are a part of life. While some of these factors are out of your control, you can also counteract them with healthy habits so you can get your best rest. Time Flies By Faster As We Get Older. Here's Why. 5 Age-Old Health Remedies That Actually Work iPhones Have A Built-In White Noise Feature That No One Knows About
The Guardian
09-05-2025
- Health
- The Guardian
Plastics in everyday objects may disrupt sleep in same way as caffeine, study finds
Chemicals in everyday plastics may disrupt the body's natural 24-hour sleep-wake cycle and circadian rhythm in a way similar to coffee, which increases the risk of sleep disorders, diabetes, immune problems, and cancer, new in vitro research shows. The study looked at chemicals extracted from a PVC medical feeding tube and a polyurethane hydration pouch, like those used by long distance runners. PVC and polyurethanes are also used in everything from kids toys to food packaging to furniture. The findings showed for the first time how plastic chemicals likely wreak havoc on cell signals that regulate the body's internal clock, throwing it off by up to 17 minutes. The internal clock is 'incredibly important for physiology and overall health', though more research is needed to know the precise consequences of exposure, said Martin Wagner, a study co-author and plastic chemical researcher with the Norwegian Institute of Science and Technology. 'This study adds to the increasing body of evidence that plastics contain compounds that cause a wide range of toxic effects,' the authors wrote in the peer-reviewed study published in Environmental International. 'A fundamental shift in the design and production of plastics is essential to ensure their safety.' The circadian rhythm is the molecular clock that regulates alertness and tiredness in relation to daylight and the dark. Shifting rhythms are linked to increases in the risk of obesity, dementia, and cardiovascular disease, among other issues. Research into plastic chemicals' toxicity most often focuses on how chemicals like phthalates and bisphenol impact the endocrine system and hormone-related effects, which can take years to manifest. The new paper looked for an impact through a different biological pathway: cells. It checked for adverse effects on the adenosine receptor, which is a key component in cellular control of the internal cock that takes part in relaying signals that regulate circadian rhythm. The biological process of how the plastic chemicals impact the body is similar to caffeine in its effects on the circadian rhythm and adenosine receptor. Caffeine deactivates the adenosine receptor, thus increasing the circadian rhythm and keeping us awake. The plastic chemicals activate the adenosine receptor, but also to have a similar effect in keeping us awake. The receptor is in the brain and 'sends signals to the body that say 'the sun is coming up – let's start the day',' Wagner said. But when the adenosine receptor is activated by the chemicals, it may not relay the message, delaying the body's natural physiological processes. While the chemicals aren't as potent as caffeine, their impact on the cellular processes happens much more quickly than plastics' impacts on hormones, Wagner said. What this means for the body is unclear, but it's probably not good, Wagner said. 'We don't know the significance of it and you could say 'Oh it's just 15 minutes so it's not a big deal', but it's such a tightly controlled clock that it's a significant shift,' he added. The study was done in vitro, meaning on human cells in a lab, and Wagner said the next step is to look at how the chemicals affect zebrafish, which have some similar physiological processes in their brains to humans. Future research will also look into which chemicals in plastic and PVC are impacting the sleep-wake cycle. PVC can contain any of 8,000 chemicals, some of which aren't intentionally added but are by-products of the production process, so the material is incredibly complex and difficult to manage. The findings of each new study will be used to pressure lawmakers to enact regulations, and to try to convince industry to remove the chemicals from the plastic, Wagner said.
