Tabisuke Tabizo / T2 High Mount Fit™

T2 High Mount Fit™

T2 High Mount Fit™ is Tabisuke Tabizo’s proprietary technology developed in pursuit of natural movement and effortless running. It is a specialized fitting system designed to eliminate interference with pelvic motion and enable the pack to be carried comfortably around the thorax.
In running packs without a waistbelt, the load must be supported primarily through the shoulder harness during while running.

T2 High Mount Fit™ combines a thorax-integrated fit, a load-supporting structure positioned on the upper back, and an adjustment mechanisms that minimizes load change.
This configuration helps avoid load concentration and reduce pain around the clavicular region, while enabling the runner to maintain a gait pattern closely aligned with that of natural running. The result is enhanced comfort and stability that support sustained high performance over extended durations.

Photo = Natsu Yanaru

Photo = Makoto Iyori

Features

A running pack that avoids pelvic interference
and is carried on the thorax.

During forward motion—such as running—the thorax slides laterally relative to the pelvis.
T2 High Mount Fit™ is designed and engineered to carry the running pack in a position
that does not interfere with pelvic motion, allowing for natural movement while wearing.

Designed to reduce shoulder loading
by supporting load across the upper scapular region.

T2 High Mount Fit™ actively supports the load of the running pack through the shoulder harness at the upper scapular region̶specifically the upper trapezius spanning from the base of the neck across the scapula and shoulder ridge̶ which is considered the least prone to pain among contact areas of the shoulder harness.

The storage compartment is positioned near the upper body’s center of mass, around the thoracic vertebrae T7‒T9, thereby reducing load on the clavicular region and promoting a more integrated and pain-reducing fit.

Engineering rationale behind the design

Studies investigating the relationship between shoulder contact areas and
perceived pain during backpack use have shown that the upper back (beige zone)
is significantly less sensitive to pain compared to the clavicular (red zone) and chest regions (orange zone).
The T2 High Mount Fit™ system is based on this biomechanical insight.

Pain sensitivity map of the shoulders

N. Wako, et al., “Characterization of shoulder load for backpack shoulder strap design based on the relationship between interface pressure and shoulder pain”, 2020 8th IEEE RAS/EMBS International Conference for Biomedical Robotics and Biomechatronics (BioRob2020), 2020.

In addition, the center of mass and load distribution of the backpack
have been carefully considered in determining the placement, shape,
and volume of the storage compartments.

Load distribution during pack wear

N. Wako, et al., “Investigation of Relationship Between Multi-Point Mechanical Stimuli on Shoulder and Overall Pain on Backpack Wearers”, 2021 IEEE/SICE International Symposium on System Integrations (SII2021), 2021.

Adjustment mechanisms
that minimize load change while running

T2 High Mount Fit™ also incorporates a dynamic adjustment system to minimize load imbalance
caused by pack displacement, as well as variations in force intensity resulting from vibration and impact during running.

Multiple harness straps allow fine-tuned control over fit, while the compression system stabilizes the storage compartment
to accommodate various load volumes and shapes.

By maintaining a consistent fit close to the initial wearing condition, the system helps reduce physical fatigue
and discomfort during high-speed or prolonged running efforts.

Adjustment mechanisms : Load Lifter

Comparison Video：Side View

Comparison Video：Back View

Adjustment mechanisms : Compression Cords

Comparison Video：Side View

Comparison Video：Back View

Test data: Relative acceleration of the pack
relative to thoracic vertebra T8
(Dynamic impact of the pack body relative to thoracic motion during running)

The running cycle was divided into 40 phases,
with the solid line representing the mean of 30 trials for each phase.
Statistical analysis was conducted to test for differences
in the mean values under different loading conditions,
and significant differences are indicated by bars at the bottom of the graph.

Test day：December 5, 2024

Supervised by: Nanta Wako,
Backpack R&D Engineer,
Ph.D. (Engineering)

Tester：Akito Nagao,
Trail Runner, YouTuber

Back pack：T2 Trail 15

Pack weight：5,091g
　Pack & Pad 583g
　Bottle & Walter 1405g
　Waterproof inner 64g
　Insulated clothing (top & bottom) 506g
　Rainwear (top & bottom) 348g
　Headlamp and spare battery 259g
　First aid kit 217g
　Wind Shell 177
　Water dispenser and water 1117g
　Energy food 415g

Gradient：0%
Pace：5’30”/km

X: Fore-aft oscillation of the pack during running

Y: Side-to-side oscillation of the pack during running

Z: Vertical oscillation of the pack during running

Supervision and data preparation

Nenta Wako

Tabisuke Tabizo Product Advisor
Born in 1983. Born in Yawata City, Kyoto.
Backpack R&D Engineer. D. in Engineering.
YouTuber：@BackpackResearcher

After graduating from Waseda University's School of Science and Engineering in 2009 and completing a Master's degree in Management Systems Engineering in 2011, he joined Ace Co., Ltd., a leading Japanese bag manufacturer, where he contributed to product development. Following the completion of his doctoral studies in Comprehensive Mechanical Engineering at Waseda University in 2021, he established a backpack technology consulting business in 2022. His expertise lies in ergonomics and backpack load reduction technology.

Main Sports Achievements
・National High School Athletic Meet, Men's Triple Jump: 5th place (Rakunan High School)
・Former Class A Professional Boxer (Wajima Koichi Sports Gym): 14 matches, 7 wins, 6 losses, 1 draw

Tester

Akito Nagao

Tabisuke Tabizo Product Advisor / Ambassador
Born in 1988. Father of three. Trail runner.
Youtuber (Vlog “Just Running Videos”)
Member of Team 100Mile (Achilles).

With over 30 years of running experience, Nagao started as a sprinter in his high school track team and became deeply engaged in marathon running during his university years. After suffering from iliotibial band syndrome in 2013, he struggled with limited mobility for years. However, during a trail run from Mt. Takao to Mt. Jinba with his local running club, he discovered that his injury didn’t hinder him on mountain trails.
In 2015, he participated in his first trail running race (Three Peaks Yatsugatake Short Course). Since then, he has gradually extended his race distances, joining Team 100Mile to pursue excellence in 100-mile races. He continues to aim for faster, stronger, and authentic performances, competing in both marathons and track meets, ranging from 1,500m to 100-mile ultra-distance races.

Main Race Results
◎2023
・Katsuta National Marathon: Personal Best (2:36:30)
・OSJ Shinshiro Trail 32K: 6th place (4:32:33)
・Mt. FUJI 100: 14th place (22:34:56)
・Fuji Climbing Race: 21st place (3:10:54)
・Fuji Climbing Relay Race: 4th place (Hundred RC)
・Tsukuba Marathon: (2:30:39)

◎2024
・HITECH Half Marathon: (1:12:38)
・Shinetsu Five Mountains Trail Running Race: 1st place (20:50:00)