Posture Support Wearable 'Seitai Shirt ONE' Launches on Makuake - Posture Expert Realizes New Challenge After 6 Years of Development

BodySprout Inc. (Headquarters: Kawasaki City, Kanagawa Prefecture; CEO: Atsushi Kobayashi) will begin pre-sales of its new product, 'Seitai Shirt ONE,' on the crowdfunding platform Makuake starting Monday, June 15, 2026. This product is a posture-support innerwear developed over six years by Atsushi Kobayashi, a posture specialist with 14 published books totaling over 230,000 copies in sales, who has been researching and guiding posture improvement for more than 20 years.

Makuake Project Page 'Seitai Shirt ONE': https://www.makuake.com/project/seitai-shirt-one/

'Seitai Shirt ONE': A New Habit of Effortless Posture Care, Supporting Those Who Strive

'Seitai Shirt ONE' was developed as a 'new habit of effortless posture care.' Born from dissatisfaction with conventional posture care products, it represents the next evolution of the 'Haku Dake Seitai®' series, which has surpassed 630,000 units sold. Responding to customer requests for an upper-body wearable, we gained new insights through market research.

While traditional products forcibly pull or stretch the back and shoulders, we focused on the aspect of 'awareness.' Being conscious of good posture is admirable, but maintaining it in a busy daily life is difficult. Moreover, forcibly correcting posture may place unnecessary strain on the back and shoulders, potentially causing injury. Therefore, while respecting the desire to 'take care,' we have pursued a method to naturally align posture without strain.

Approaching the Body's Center: The 'Dantian'

'Seitai Shirt ONE'—Guiding the Body to Proper Posture Naturally and Without Conscious Effort, Simply by Wearing It

The greatest feature of 'Seitai Shirt ONE' is its approach to the 'dantian,' the body's central core. The dantian is located slightly below the navel and is a crucial point for core stability in sports and martial arts. When posture collapses, it is often not just the back but the entire body's balance that is affected. 'Seitai Shirt ONE' is designed to support the dantian, thereby naturally and effortlessly supporting correct posture.

Three Support Structures Aimed at Achieving a 'Body That Naturally Aligns Without Conscious Effort'

'Seitai Shirt ONE' incorporates three mechanisms to support posture (Utility Model Registration: No. 3255992).

1. Dantian Support Structure

A unique abdominal structure gently supports the dantian, the body's central core.

2. Thoracic Spine Support Structure

Targets the thoracic spine—a particularly important area of the back—and supports natural chest expansion.

3. Dual-Point Support Structure

A unique design that simultaneously engages both the dantian and thoracic spine to stabilize the core without strain.

Our goal is not posture correction, but rather 'creating an environment where posture can be naturally and effortlessly aligned without conscious effort.' In other words, the aim is to create a state in which the body naturally aligns simply by wearing the shirt.

Background of Development

The development of this product was significantly influenced by encounters with entrepreneurs and business professionals. Those who challenge themselves to contribute to society—through long meetings, business trips, travel, and public speaking—often end up neglecting their own bodies. With the intention of 'supporting those who strive, starting from their bodies,' we developed this product.

BODY SPROUT's Vision for the Future

Our goal extends beyond being a health product manufacturer—to 'create environments that enable healing.' We aim to spread environments in which the body naturally aligns through everyday life, without requiring special effort. 'Seitai Shirt ONE' represents a new challenge that embodies this vision.

Developer's Comment

Atsushi Kobayashi, CEO, BodySprout Inc.

'For over 20 years, as a posture specialist, I have worked to guide people from posture to health. The conclusion I have reached is that 'methods requiring effort won't spread.' Seitai Shirt ONE was developed to create an environment where even busy modern individuals can effortlessly align their bodies. I sincerely hope this product becomes a supportive presence in many people's lives.'

Product Overview

Product Name: Seitai Shirt ONE Pre-sale Start Date: Monday, June 15, 2026

Sales Method: Makuake pre-sale

Planned General Retail Price: 9,900 JPY (tax included)

Color: Gray

Sizes: M, L, LL

Makuake Project Page

https://www.makuake.com/project/seitai-shirt-one/

Company Overview

Company Name: BodySprout Inc.

Representative: Atsushi Kobayashi

Headquarters: B-123, Miyamaedaira 3-12-3, Miyamae-ku, Kawasaki City, Kanagawa Prefecture Business Activities: Chiropractic and holistic therapy clinics, product development, e-commerce, practitioner production consulting

Website: https://bodysprout.com/

BodySprout Online Store: https://store.bodysprout.com/ Email: info@bodysprout.com

Press Inquiries: 044-863-7686 General Inquiries: 0120-706-089