We appear to believe that pushing ourselves to the absolute redline limit is reasonable. We are expected to replace our restorative processes, including time for sleep, being in nature, exercising, eating healthily, and breathing deeply, with more time on task, more time hammering away at whatever it is we hammer away at.
And what is all this go, go, go and do, do, do doing
to our health and wellbeing? We know the answers: Stress is high and rates of stress-related illnesses are climbing. Depression and anxiety are pervasive. Even adolescents are experiencing escalating panic and hopelessness.
The truth is that humans are resource-limited; we aren’t born with a solar panel on our backs. Just like every biological organism we need to recharge on a regular basis.
The good news is that nature understands the importance of recovery and it doesn’t leave such a critical process to chance. Evidence for this is that all living things on the planet—from plants and complex animals to the tiniest bacteria—are guided by rhythms. Rhythms provide set periods for peak energy and activation and periods of low energy. I’ve been studying these rhythms in my sleep lab for the last 20 years. I’ve developed terms to simplify these concepts. I call the first half of the rhythm the Upstate, which is reserved for activation, excitation, instigation, and motivation. I call the second half the Downstate, which is reserved for restoration, renewal, replenishment, and repair.
Rhythms are a universal principle of all living things because nature repeats itself when it has found a pattern that works. All of our internal systems operate via rhythms—breathing, heart rate, sleep, exercise, metabolism—and we as individuals function best when we get our own personal rhythm in sync with the larger rhythms of nature.
This rhythm of Upstate and Downstate has been cycling since the beginning of time, and we see that in the way nature has organized what happens in our bodies as we move from day to night and back again. Our most energy-requiring activities have been relegated to the daylight hours; this is the time for hunting and foraging, exploring and conquering, and information gathering and learning. And all of our mental and physical systems are fully supported by having naturally greater energy availability and stronger cardiovascular function during the Upstate day. Our metabolism is set up for eating and processing our foods and turning them into energy most efficiently during the daylight hours. Our cognitive processes and ability to self-regulate our behaviors and our emotions are at their highest during the day.
Our autonomic nervous system also divides itself between day and night in its own, related rhythm, reserving peak sympathetic fight-or-flight activity—activity I call REV—for daytime and peak parasympathetic rest-and-digest activity—activity I call RESTORE—for nighttime.
I like to think of them as twin subengines, each with different jobs that keep each other in check. REV is activated when you have any stressful experience (good or bad), making sure you have the resources you need for quick mobilization. This is appropriate when it happens during the day, but as with many things in life, too much REV can be a bad thing and can wreak havoc on your cognitive, immunological, metabolic, and cardiovascular systems. It’s RESTORE’s job to reign in REV. RESTORE helps with healing broken tissue, calming racing hearts, replenishing energy supplies, strengthening cognitive systems, and calming our fired-up emotions.
As the sun works its way across the sky and dips below the horizon, RESTORE starts to turn on, indicating the beginning of the Downstate. This is the time we head for the safety of our burrow to initiate the processes that can only occur during rest time. During this precious period, you can turn your attention inward and start the quiet labor that keeps you intellectually sharp, helps you learn new tricks, heals growing muscles from your workout, lessens emotional triggers, restocks your cells with much-needed proteins, and gives your heart and metabolism a much-needed holiday. All of which sets you up for success come morning.
So, how do you make the most of this Upstate-Downstate rhythm? Many metabolic processes function better when the sun is out. For example, processing food in the body produces heat and burns calories via diet-induced thermogenesis, which peaks in the morning and is two-and-a-half times higher in the early hours than at night. Your body’s ability to process glucose, which provides the body and brain with energy to take action and think, is also faster early in the day. Insulin, which transports glucose from the bloodstream into your organs, shows high levels by day but low levels at night—lounging on the couch snacking at night leaves glucose in the bloodstream that ultimately gets stored as fat.
You can sync up your eating habits with the Upstate of your metabolic system by frontloading calories—making breakfast the biggest meal of the day. Studies support the benefits of shifting eating times to earlier hours. Beyond physical fitness, earlier mealtimes are also associated with higher levels of melatonin, our bodies’ natural sleep hormone. This demonstrates that all of your biological subengines are interdependent; eating patterns affect sleeping patterns, sleeping and exercise patterns affect alertness and metabolic health, and so on.
When we honor these universal Upstate/Downstate rhythms, we bring all these systems into alignment. By making room in our modern lives for the ancient rhythms of the Downstate, we can have the peace of mind and body to accomplish our loftiest goals and tune in to our highest and best selves.