"I'm just driving, but by the time I arrive I'm completely worn out."

"Getting stuck in traffic alone feels like it drains a whole day's worth of energy."

You're supposedly just sitting there, just moving from one place to another — so why does the fatigue you feel in a car weigh so heavily? Today we'll look at the theme of "in-car fatigue causes" from both the mechanics of the body and Japan's travel wisdom dating back to the Heian period.

Why the Car Is So Tiring — the Body's Sensitivity to Vibration

There's an international standard called ISO 2631-1, set by the International Organization for Standardization, covering whole-body vibration. According to this standard, a seated body's sensitivity rises for vibration in specific frequency bands. It's been pointed out that vibration transmitted to the body through the seat, from the engine or the road surface, tends to overlap closely with exactly this sensitive frequency range. In other words, the sense that "my body somehow feels heavy" has a part that can be explained as an actual bodily response, not just imagination.

Research examining fatigue while driving often uses heart rate variability to estimate the state of the autonomic nervous system. During traffic jams or long stretches of monotonous driving, the sympathetic nervous system, which activates the body, tends to become dominant, and this is thought to build into a strong sense of fatigue when it accumulates. This is also a field where institutions like Nihon University's College of Science and Technology and the Toyota Central R&D Labs have conducted ongoing research into physical strain during urban driving and fatigue assessment while driving. A car cabin, where vibration, noise, and monotony all pile on continuously at once, places more of a burden on the body than you might expect.

Katatagae | People in the Past Also Tended to "Travel" Itself

During the Heian period, there was a custom called katatagae, rooted in Onmyodo. On a day when a directional deity like Tenichijin was believed to occupy the direction of your destination, you would first head in a different direction, spend the night there, and only set off toward your actual destination the next day, approaching from a different direction. The oldest recorded instance of katatagae is said to date to the year 865, and the custom is said to have been deeply woven into the daily lives of the aristocracy.

This wasn't an idea that has passed modern scientific scrutiny — it's understood as a custom rooted in the belief system of Onmyodo at the time. Still, it's interesting that people didn't treat the act of "traveling" lightly, and took the trouble to tend to their state along the way. For us today, often so focused on simply reaching our destination that we let the car, our "time in transit," become an empty stretch where fatigue just accumulates, this offers a suggestive perspective.

Scent and Habits for Tending to Your Car

Take a Breath and Switch On With Scent Before You Drive

Before starting the engine, take one deep breath and breathe in a scent before setting off. This alone lets you deliberately mark the start of your driving time.

Ventilate Frequently to Refresh the Air

A car cabin easily becomes a small, sealed space. The habit of cracking a window at a red light or a rest stop to refresh the air helps ease the heaviness that comes from stagnant air.

Don't Keep Looking at Your Phone in Traffic

Glancing at your phone while stopped piles even more visual information on top, keeping what should be a chance to rest from actually resting. Use those few dozen seconds at a red light to turn your attention to scent or breathing instead of a screen.

Deliberately Release Tension in Your Seat Position and Shoulders

Vibration and tension often leave your shoulders and neck tight without you realizing it. Small adjustments — rolling your shoulders lightly at every stop, rechecking your seat position — also help reduce the strain that builds up over time.

Reset With Scent

No.17 Deep Reset, made with digital environment stress in mind, pairs well with commute and travel care. It works as a quick spritz in the car when your head feels foggy and heavy, or as a switch before and after driving. After coming home, some people use the same Deep Reset bath salt to slowly reset starting from a foot bath. For more, see the Reset Series.

Summary

• A seated body tends to respond sensitively to vibration in specific frequency bands, as shown by the international standard ISO 2631-1
• Traffic jams and long stretches of monotonous driving make the sympathetic nervous system more likely to dominate, thought to accumulate as fatigue
• The Heian-period custom of katatagae, an idea of tending to travel itself, has something to say to commute care today
• Small habits — scent, ventilation, keeping your attention off your phone — can reduce the strain of time spent in the car

On digital environment stress, see Why Computer Work Leaves You So Tired | A Scent Habit to Settle Your Autonomic Nervous System. On screen fatigue, see Why Focused Computer Work Gives You a Headache | EMF Care and a Scent-Based Reset Habit.

References: The ISO field of standards for evaluating whole-body vibration, engineering and physiological research on fatigue assessment while driving, and research on heart rate variability as an indicator of autonomic nervous system state.