STC Japan

STC Japan is an educational organization that aims to spread the latest training theories and practices in Japan, based on "Strength Training and Coordination: An Integrated Approach" by Frans Bosch.

We promote a transition from traditional linear training to an approach based on non-linearity, complex systems, and chaos theory, aiming for more effective strength training and optimized coordination.

Officially launched in May 2023, STC Japan brings to Japan the STC program originally started in South Korea by Professor Il-Bong Park (international name: James Park). The program was adopted in the strength training of the Japan national rugby team during the 2015 Rugby World Cup and provides a training approach that can be applied to a wide range of individuals, from athletes to rehabilitation patients. (Contributed by Frans Bosch Systems)

The STC Course is composed of five courses in total.

These include the Basic Course, which teaches the foundational theories of STC; the Advance Course, which focuses on sport-specific training; the Rehabilitation Course, which specializes in applying STC theory to rehabilitation; and the Professional Course, which provides practical knowledge such as the constraint-led approach.

After completing all of these courses, participants can enroll in the Master Course, which further develops practical applications in the field and detailed programming based on the knowledge gained so far.

CHAOS® AquaBag / AquaBall

Unlike traditional weights, the CHAOS® AquaBag and AquaBall are dynamic training tools that require balance, coordination, and core stability in every movement, thanks to the shifting water inside the bag.

The adjustable load allows users of all levels—from beginners to advanced athletes—to train effectively. With a compact and portable design, these tools make it easy to perform high-quality training anytime, anywhere.

The CHAOS® Ball Stability System leverages the unpredictable movement of water to create a chaotic environment that stimulates the body’s motor control system. In response, the muscles surrounding the joints contract in a coordinated and immediate manner to stabilize them—promoting a mechanism known as co-contraction.

This mechanism not only helps prevent injuries, but also eliminates muscle slack during explosive movements, resulting in a faster Rate of Force Development (RFD).

Thanks to its portability and easy setup, the CHAOS® Ball can be used not only in traditional gym settings but also on the field or in space-limited environments. By switching out attachments, it can also be adapted for sport-specific training, making it a versatile tool for athletes and professionals alike.

The CHAOS® Barbell Bands are the world’s first adjustable resistance bands specifically designed for Olympic-sized barbells. With just one CHAOS® Barbell Band, you can create over 20 different resistance levels.

Whether you're suspending weights to introduce external perturbations or anchoring the barbell to the floor, this single tool meets a wide range of training needs with versatility and ease.