[Model: Hitomi Kaji] Embracing the 100-Year Life—Staying Physically and Mentally Ready to Pursue What We Love at Any Age

How do professionals across sports, business, art, and culture engage with their bodies and unlock their full potential?
We speak with individuals who continue to push boundaries in their respective fields, asking them how they approach “conditioning” in their daily lives—and how it supports both their physical and mental performance.
※ Conditioning refers to the proactive care of one’s body and mind to stay in optimal shape for work, performance, and everyday life.

Our guest this time is Hitomi Kaji, a model widely admired by women for her toned physique and commitment to gut health—a practice she has continued since her twenties.
For Hitomi Kaji, the key to maintaining a healthy body and mind lies in one simple approach to conditioning: staying consistent with the basics.

※At TENTIAL, we define conditioning as the practice of optimizing all factors that affect physical and mental well-being, with the goal of enhancing overall life performance.

Gentle gut care with warm water and fermented foods—no stress, just balance.

— Long before “Kaji Body” became a trend or gut health became a buzzword, you were already mindful of your digestive health and living a wellness-focused lifestyle. Looking back, how would you define “conditioning” today, in your own words?

To me, conditioning isn’t just about maintaining a beautiful appearance—it’s about keeping my internal organs functioning well and ensuring that my mind and thoughts are clear and energized.
To make that happen, I focus on three key pillars: gut health, exercise, and sleep.
Rather than relying too heavily on just one, I try to maintain a balance that works best for me, giving each the attention it deserves.

— What inspired you to start focusing on gut health?

I was physically weak as a child and spent a lot of time in and out of the hospital.
Because of my health, I often couldn’t do the same things as my classmates, and I lived with many limitations.
Naturally, I began learning more about health and nutrition from an early age.
Looking back, I think that’s where my focus on gut health really began.

— What does your daily gut health routine look like?

I always start my day with a glass of warm water.
It helps warm up my body, boosts circulation, and even reduces bloating. It’s simple, costs nothing, and anyone can do it—so why not? [laughs]
I also regularly eat fermented foods. Japan has so many options like natto, kimchi, and amazake, so it’s easy to incorporate them into everyday meals.

Fiber is also really important—especially soluble fiber found in seaweed.
It helps relieve constipation and gives your gut a gentle cleanse, so I definitely recommend adding it to your diet.

Just 10 minutes of cardio each morning clears my mind for the day ahead.

— What kind of exercise do you do?

I’ve been practicing Pilates for about 12 years, but recently I’ve also started doing 10 to 15 minutes of cardio every morning.
Specifically, I go for a run at a pace of around 7 to 9 km/h. I started running to help clear my mind and body at the start of the day.
I actually have a lot of new projects coming up—like a collaboration café and launching an online community—so there’s a lot I need to think through every day.
That’s why I wanted to find a way to “switch on” my brain in the morning, and running has really helped with that.

After running at the gym, I usually stop by a café.
It’s become a daily routine—organizing my schedule for the day, reading a book, or reflecting on future plans.
It’s a quiet moment I really value to reset and prepare myself for what’s ahead.

— Just 10 to 15 minutes of running?
That’s surprising—I assumed you’d be doing something much more intense to maintain your signature “Kaji Body.”

People tell me that all the time! [laughs] But honestly, that’s really all the exercise I do right now.
There are so many standard goals out there—like “run for at least 30 minutes to burn fat” or “walk 10,000 steps a day.”
But I try not to get too caught up in those numbers. I focus more on what feels right for my body.

What I trust isn’t numbers—it’s myself.
I listen to my body, my energy levels, and what fits into my lifestyle at the time. That’s how I decide what kind of exercise to do and for how long.
Most importantly, I focus on consistency. If a workout is too intense, I know I won’t stick with it—so I keep things sustainable.

Because I struggle to fall asleep, I pay extra attention to my sleep environment.

— Do you have any personal rules or routines when it comes to sleep?

I aim for around seven hours of sleep each night.
I’m naturally a long sleeper—I could easily sleep for 12 hours if I had the time! [laughs]
But for my current lifestyle, seven hours feels just right.

I make sure the lighting and room temperature are comfortable before bed.
As for baths, I’ve learned that getting into bed right after a hot soak raises my body temperature and makes it harder for me to fall asleep.
So I try to take a bath at least two hours before bedtime.

I’m not good at doing nothing—I’m the type who’s always thinking about something.
That’s why, before bed, I make a conscious effort to put my phone away and clear my mind as much as possible.

— Is there anything else you’re particular about?

In the colder months, I make sure to keep my neck, wrists, and ankles covered while I sleep to avoid getting chilled.
I often use things like leg warmers to stay warm and comfortable through the night.

I’m also a big fan of TENTIAL’s recovery wear.
It keeps me warm without feeling stuffy, and the fabric is breathable and lightweight.
You can really feel the care and research that went into every detail.
With so many options—short sleeves, long sleeves, different materials—I love being able to choose what suits the season.

Conditioning my mind and body so I can give my all to what I love.

— We’ve heard that you also place great importance on conditioning your mind.

Yes. I often think about things with the mindset of, “What if I live to be 100?”
In a career like mine, there’s no guarantee that the kind of work I do now will still be available in the future.
And honestly, we no longer live in a time where people stick to one job for their entire lives.
Our lifestyles and interests naturally evolve over time—and I try to keep that in mind.

When something I truly want to do comes along, I don’t want to have to give it up because I lack the physical or mental energy.

You could say that I focus on gut health, exercise, and daily conditioning so that I can always be ready to give my all to my dreams and the things I truly want to do.

— It’s really about how to live a long and fulfilling life, isn’t it?

Yes. When your body and mind are healthy and fulfilled, you naturally feel more at ease—and I truly believe it changes your personality.
That’s exactly what happened to me. I stopped getting irritated, and I no longer snap at others.
When you become more kind to yourself, you become kinder to those around you—and that kindness spreads.
In the end, it makes everyone a little happier.

I think those thoughts may have come from my childhood experiences of being sick so often.
I was a quiet, introverted child who had trouble making friends because I was always unwell—I spent most of my time reading books. [laughs]
Looking back, maybe that’s what shaped the way I see health and life today.

I always remind myself how important it is to be healthy.
Without that foundation, it’s hard to even take the first step toward achieving your dreams.
Good health isn’t just a goal—it’s what makes everything else possible.

TENTIAL: A brand built on athletic insight and scientific evidence.

— Could you share your thoughts on TENTIAL’s products?

I first came across TENTIAL at a pop-up event in a department store.
As a recovery wear brand that incorporates insights from athletes and health experts, it really appeals to someone like me who’s a bit of a wellness and knowledge nerd! [laughs]
What stands out to me across all the pieces I’ve tried is how warm they feel.
At the same time, they’re incredibly lightweight and easy to move in.

The item I wear most often is the MIGARU Hoodie.
I love how the fabric is thick and structured—it doesn’t lose its shape and gives off a clean, put-together look.
It’s my go-to whenever I head to the gym.
At home, I often wear the BAKUNE Pile, made with soft pile fabric.
It’s fluffy, cozy, and feels amazing on the skin—perfect for lounging!

When I pair it with the matching shorts, it looks super cute and makes my time at home even more enjoyable.
I also wear the compression socks the night before a photo shoot—they’ve become part of my routine.
And the sandals are incredibly comfortable too—I really like how they feel.

— Thank you for sharing so many of your favorites with us!

I’m drawn to products that have a story behind them.
TENTIAL was founded by someone with a background in sports, and every item is developed with a solid scientific foundation.
Hearing that kind of story builds a deeper sense of trust for me.

People today are incredibly busy.
Even if they want to take care of their health, many simply don’t have the time to commit fully.
That’s why I think using items developed by professionals—like those from TENTIAL—can be a smart and helpful option.
By combining those with things like gut health practices or regular exercise, which take more time to show results, you can create a more balanced approach to conditioning.

Model & Certified Gut Health Planner, Hitomi Kaji

At age 26, Hitomi Kaji entered the Tokyo Girls Audition (TGA) and won the Grand Prix in the artist category.
She made her debut as a recording artist at 28.
Having been physically fragile as a child, she developed a deep interest in nutrition and fitness—leading to her toned and graceful figure, famously known as the “Kaji Body,” which has become a source of inspiration for many women.
She is also active as a radio personality and author, having published a book about gut health, a wellness practice she has followed for many years.