Boost Your Immunity During Flu Season by Sorting Out Your Circadian Rhythm and Sleep

In the past, we’ve shared several posts about how sleep improves performance and recovery, and what athletes like triathlete Sarah True, Vikings All-Pro tight end Kyle Rudolph, and runner/coach/supermom Mary Johnson do to get high quality slumber every night. But there’s something about this time of year that seems to mess with your sleep, isn’t there? Often it’s a combination of the cold weather, the early evening darkness, the rebound after a jam-packed holiday calendar, or all of the above. 

We know that when you’re stressed out and sleep and sun-deprived, you’re not performing at your best, bouncing back between training sessions, or bolstering your immune system to fight off the flu season that’s been making its rounds. The aim of this article is to help you get your body back on track so you can crush your 2020 goals and stay healthy doing it. 

Falling Back or Falling Apart?

We’re a few months past the clocks changing, but you might still be struggling to get your sleep schedule back on track and waking up feeling groggy each morning. That’s annoying in general, but beyond feeling frustrated, you might also be undermining your training gains and putting your health in jeopardy if your sleep is out of whack. We spoke about this with Kristen Holmes, a Vice President at the sleep-wearable and technology company WHOOP who played for the women’s US field hockey team and coached Princeton to a national title. According to Holmes, lack of self-awareness can often prevent us from even realizing we’re not getting enough rest. 

“We tend to over-report how much sleep we get, partly because the time we spend in bed isn’t all devoted to deep sleep,” she said. “We also don’t often perceive our cognitive or physical declines related to sleep, so we can mistakenly think we’re getting enough. So we end up adapting to a sub-optimal level of function. Technology can help draw our attention to such deficits, and help us be more intentional in our actions. Then it’s simply a matter of repeating such positive behaviors – like getting more sleep – as often as possible.” 

If you’re the kind of person who is consistently low on energy, then it’s time to make some changes. The first step in doing so, according to Kristen, is to simply listen to what your body is telling you.

“It’s important to understand your chronotype and give in to your biological pressure to get natural sleep, because then you’re in lockstep with what your body wants to do,” she said. “Enable the process of self-regulation by going to bed at the time you feel sleepy, which will put you on a consistent sleep and wake-time schedule. That’s the lowest hanging fruit for resetting your sleep at this time of year. Your gut, brain, hormones, and all the other clocks that regulate your body become more aligned when you stabilize your sleep-wake timing. There’s this cascade of positive effects from just going to bed and getting up at the same time every day.”

Start Your Day Right

In addition to going to bed at a consistent time each night and setting your alarm for a regular wakeup, there are some other things you can do to overcome any kind of circadian rhythm disruption. The first couldn’t be simpler: open your front door and go outside. 

“Light is one of the primary cues for re-establishing our natural sleep cycle,” Kristen said. “Just one hour time change, from things like travel or when the clocks fall back, is enough to get us out of sync, as can going to bed later for holiday events. The best strategy is to expose yourself to sunlight when you wake up in the morning. The other thing that tells you it’s time to be awake is the temperature of the ground, so I’m a big fan of grounding. If you can go out in bare feet or minimal footwear, this can help remind your body that it’s time to be alert and get going.”  

The latest evidence backs up what Kristen is suggesting. A paper published in Sleep Medicine concluded that increasing morning light exposure and restricting it at night did more to help people adjust their sleep-wake time than the time they went to bed and got up.¹ 

Do the D

While getting outside for a few minutes in the morning and taking a longer walk later can help recalibrate your sleep-wake cycle, people living in the Northern Hemisphere often struggle to get sufficient sun exposure at this time of year to create adequate levels of vitamin D. In which case, you would do well to start taking 2,000 to 5,000 IUs of vitamin D daily. Combining this with vitamin K can help absorption. 

Another tactic that can help keep your circadian rhythm in sync during fall and winter is exposing yourself to red light several times a week. A study of Chinese basketball players published increased levels of melatonin (which is key in helping you drift off and a key ingredient of Momentous Sleep), which may explain the increase in their sleep quality. An added bonus? The players who received 30 minutes of red light therapy nightly for two weeks also increased their endurance.2 

“Combining red light therapy with a vitamin D supplement can cue your system to work synchronously,” Kristen said. 

Fight Off Colds and Flu

Another factor that makes things harder for our bodies in fall and winter is that our immune system is constantly bombarded by bacteria and viruses. With this in mind, getting a flu shot has become a go-to for millions of people, but Kristen cautions that you should rest up first. 

“If you’re going to get a flu shot, make sure you’re well recovered first so that your body can process it and it’s helpful, not harmful,” she said. 

Another way to bolster your immune system is to mind your micronutrients. A study conducted out of University of Otago in New Zealand asserts that vitamin C plays a potent role in killing off microbes, increases the proliferation and diversity of disease-fighting B and T cells, and clears out byproducts from sites of infection. “Furthermore, supplementation with vitamin C appears to be able to both prevent and treat respiratory and systemic infections,” the authors note. They recommend 100 to 200 milligrams daily, with higher intake if you’re already sick. You could also incorporate more oranges, lemons, grapefruit, and bell peppers into your diet.3

Breathe Your Way Through Stress

One of the biggest yet largely overlooked factors that compromises both sleep and immune function is stress. And while taking a nice hot bath, listening to music, or reading at night can all help, undoing all of the day’s emotional damage at night can be too little, too late. 

“Instead of waiting to deal with stressful events in the evening when we should be winding down, we need to find ways to manage stress proactively to prevent it accumulating,” Kristen said. “When we’re already run down, it’s one of the main things that makes us more likely to get sick and injured. Understanding the toll that non-workout stress takes on you and getting better at managing it is huge for making the most of your recovery.”

One of the simplest ways to bust stress during the day is to schedule regular check-ins with your breath. While we pay more attention to eating and hydrating, breathing is arguably the most elemental thing we do as humans, but it’s often last on the list of things we think about because it happens automatically. Simply being conscious of your breath for a minute or two at a time can help you reset your physical and emotional state, calm anxious thoughts, and offer many of the benefits of a longer meditation session. Findings released in the summer 2017 edition of Frontiers in Psychology revealed that breathing slowly from the diaphragm even lowers stress at a cellular level, by reducing cortisol production.4 Short bouts of daily breathwork also increased participants’ attention span. 

“Box breathing can help regulate your autonomic nervous system,” Kristen said. “It offers both mindfulness and a trigger for parasympathetic recovery. 90 seconds is enough – just breathe in for four seconds, hold for four, out for four, and hold again for four. If you box breathe four or five times throughout the day, you’re putting in periods of intentional rest, which will have a powerful effect because you won’t accumulate too much negative stress.” 

The Momentous Difference

The formula is a combination of three ingredients: Melatonin, Magtein®, (Magnesium L-threonate), and Wild Jujube Seed Extract to help reduce nighttime anxiety, gently fall asleep, and improve circadian rhythm to achieve higher quality sleep. NSF Certified for Sport and Informed-Sport Certified.

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1 – K Appleman et al, “Controlling Light-Dark Exposure Patterns Rather than Sleep Schedules Determines Circadian Phase,” Sleep Medicine, May 2013, available online 

2 – Jiexiu Zhao et al, “Red Light and the Sleep Quality and Endurance Performance of Chinese Female Basketball Players,” Journal of Athletic Training, November 2012, available online at 

3 – AC Carr and S Maggini, “Vitamin C and Immune Function,” Nutrients, November 2017, available online at 

4 – Xiao Ma et al, “The Effect of Diaphragmatic Breathing on Attention, Negative Affect and Stress in Healthy Adults,” Frontiers in Psychology, July 2017, available online at

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