Circadian Rhythms Are Like Walking

Have you ever timed up your steps with a friend’s as you walk on the sidewalk? Or synced up your steps to match a pattern of tiles on the ground? 

Our bodies know what it’s like to find a groove, a pattern, a rhythm. It turns out, that’s not just true for your feet—it’s also true for your body’s circadian clock.

Circadian rhythms, the internal clocks that govern everything from your sleep cycle to your immune response and grip strength, work in much the same way. They’re adaptable, resilient, and sensitive to the signals in their environment, and they’re happiest when those signals are clear. Let’s break it down with a little metaphor.

Walking the Rhythmic Sidewalk

Imagine I give you a yellow shoe and a black shoe. You’re walking on a sidewalk with alternating yellow and black tiles. Your job? Step with the yellow shoe on the yellow tiles, and the black shoe on the black tiles.

If the tiles are spaced just right—not too long, not too short—you’ll naturally adjust your stride to match the pattern. You’re entraining: matching your internal timing (your gait) to external cues (the sidewalk). If you needed to stretch your step a little or shorten it slightly, you could. That’s the flexibility of your walking rhythm, and your circadian clock is flexible in much the same way. 

Suppose you come upon a puddle on the sidewalk. You step around it, maybe break the pattern for a moment, and then fall back into it without much trouble. That’s robustness—both your walking rhythm and your circadian rhythms can bounce back from disruption.

Now Let’s Talk Light

For your body’s clock, it’s not about colored tiles—it’s about light.

Your circadian rhythms are constantly syncing themselves to the light in your environment. Left totally on their own, your body’s rhythms would likely run slightly longer than 24 hours. But because you’re exposed to daylight, your brain tweaks the clock to fit the world’s 24-hour schedule, just like your feet adjusted to the sidewalk pattern.

This synchronization to light and dark is critical. Entrainment to your light/dark schedule is how your brain knows when to wake up, when to feel hungry, and when to sleep.

The Sidewalk Gets Complicated

But what happens when the sidewalk starts sending mixed signals?

Let’s say you’re back on the sidewalk, but now the pattern gets weird: yellow tile, black tile, short grayish tile that’s kind of in between. Keep matching yellow with yellow, black with black! I yell. You can try, but your stride is off. The rhythm feels forced. You’re not walking smoothly anymore. You’re stepping, stumbling, constantly having to adjust and think about where your foot goes next.

That’s what happens when we give our brains ambiguous light cues. Artificial lighting late at night, inconsistent sleep schedules, or even the shift to Daylight Savings Time all blur the signals your brain relies on. The rhythm falters, and the consequences show up in your sleep, mood, metabolism, and overall health.

Keep the Rhythm Smooth

Just like walking is easiest when the tiles are clear and evenly spaced, your body functions best when your circadian rhythms have clear, consistent cues. Think: Regular wake times, predictable light exposure in the morning, and winding down with dim lighting at night.

Sleeping should be as effortless as walking, and one way to make your sleep easier is to pay attention to your light exposure. Another way? Download Arcashift, your personalized circadian coach.