Aimed for a personalized comfort and fit – “Foot + craft”

From experiences of supporting many athletes, we have been paying attention on the feet in order to develop sports gears that are useful for many users. In order to jump higher and move forward strongly, contact points where capture the ground and convey power are important. On the other hand, the collapse of feet can become a cause of various troubles. Like the work done by craftsmen who create fine pieces with a lot of care, we have created Footcraft insole with serious considerations to the feet.

Insole for Foot Trouble Solution “Footcraft”


[Feature 1] Optimal support with selective arch type

From the 3 arch types, you can choose the type best suited for your own feet. Footcraft gives you a personalized comfort and excellent fit.

[Feature 2] Ideal Alignment by Windlass Mechanism

Windlass Mechanism is a phenomenon in which the arch and rigidity of a foot becomes stronger by raising the toes.
Design based on the Windlass Mechanism which is the natural foot movement. It properly supports the ideal foot alignment and leads the tilt of the foot to the more neutral state with less load, and reduces the impact. Foot troubles can be reduced.

[Feature 3] High Stability and Flexible Support

Gradual support by “Core Stabilizer” and “Flexible Holder” provides high stability on the unstable heel and flexible support that follows the arch movement.




I will explain the importance of "foot arch", "foot alignment" and "insole" and how to select the correct insole according to each case.

Dr. Jun SASAHARA is an orthopedics doctor conducting medical practices using a ultrasound imaging device for various sports injuries (especially foot and ankle).

Foot Arch and Foot Alignment

[Point] When the foot arch collapses, the foot alignment also collapses, and it will cause various pain.


Foot arch is the foot framework that is composed of ligaments and muscles/tendons with three arches, 2 longitudinal arches and 1 transverse arch. The Foot arch plays a cushioning role when walking on the ground and is a key for the Windlass Mechanism. The Windlass Mechanism is a mechanism of the foot in which the arch rises as the toe rises upward when kicking out (toe separating period) the ground by walking (toe separation period), enables efficient walking. If the arch collapses, this mechanism will not work properly. Thus it may cause pain on the feet, Achilles tendon, and even around the knee.

[Foot alignment]

When the medial longitudinal arch, which makes the plantar arch collapses, the plantar arch disappears and becomes a flat foot (Overpronation). Looking at this state from the rear, the angle between the lower leg and the heel (Leg Heel Angle, LHA) is larger as shown on the left figure. If the foot alignment is not in the proper position, it may cause pain on the feet, Achilles tendon, and around the knee.

Importance of Insole

[Tip] The roles required for insole are stabilizing the arch support and heel.

[Arch support effect]

As the arch collapses due to fatigue and aging, the risk of causing various pains mentioned above increases. Therefore, it is important to support the arch (Arch Support) so that it will not collapse. It is considered that taping, functional sock, and insole work for the purpose.
What you should not misunderstand is that it is not about just raising the arch.
Even if the arch is raised forcibly with insole, to those who originally have low arch, it will give an opposite effect with pain and discomfort.

[Stabilization of heel]

If the heel is unstable, it may affect and cause pain on not only foot and Achilles tendon, but also on knee and hip joint. Insole has not only the arch support effect, but also has the heel stabilizing effect. Stabilizing the feet firmly is important. Not only that it works for preventing foot injuries, it is also important for knee and hip joint.


[What is Plantar Fasciitis?]

Plantar fasciitis is the symptom that plantar fascia, which connects the calcaneus bone of the heel and proximal phalanx of the foot finger, gets pain by degeneration or inflammation. It is the most frequent symptom that occurs on heels of adults.


The insertion of plantar fascia and the bone of the heel is not only the part where impact applies at landing, but also it is being added the power of pull toward the toe by Windlass Mechanism. By repeating walk or run under this condition, plantar fascia keeps on being damaged little by little, and eventually gets deformed or pain.

Expected Symptoms

Heels can become painful by playing sports or long-time walk. The most known feature of the symptom is getting ache at the first step after waking up. The ache on the back of the heel by pushing is often seen, but the ache around the plantar arch is also seen, depending on where the symptom has appeared.

Frequently Caused Sports and Movements

Running or sports with jumping movements such as athletic sports, soccer, and rugby.

Treatments and Preventions

The basic treatment for plantar fasciitis is physical therapy such as stretch exercise, and wearing insole. Not only on the plantar arch, stretch exercise on the Achilles tendon is also important for prevention. If the condition does not get better, medication with drugs, injections, ESWL (extracorporeal shock wave therapy) will be applied, depending on the condition. In case of the severe condition, surgical intervention may be needed.

[What is Achilles Tendonitis?]

Because the Achilles tendon keeps getting stresses from running and jumping, pain often occurs around it. The injuries on it can be roughly classified into the injury of the Achilles tendon, around the tendon, and of the insertion of the calcaneus.


The Achilles tendon is a common tendon made of gastrocnemius muscle and soleus muscle. Strong force is applied during sports. At the insertion, compression is also added between the calcaneus and the tendon. It will cause the deformity or inflammation, and consequent pain on it.

Expected Symptoms

The common symptom is swelling of the fascia and synovial bursa around the Achilles tendon that causes pain with walk and exercise. If the symptom is severe, the swelling could be easily detected visually. At the injury of the insertion, the bone can become swollen and bulgy (Haglund’s Deformity).

Frequently Caused Sports and Movements

t is seen among sports that require frequent run and jump, such as athletics, volleyball, and basketball.

Treatments and Preventions

First of all, wearing wider-front shoes is important. Then stretch and exercise of the foot and fingers. If the symptom could not be recovered with them, the next step is applying medical treatment or functional orthotic treatment including wearing insole. In case of the severe condition, surgical intervention such as osteotomy surgery may be needed.

[What is Symptomatic Accessory of Navicular Bone?]

It is the condition that the extra bone of os tibiale externum located on the inner side of the navicular bone develops pain i.e. by wound. It is often seen among adolescents who play sports.


The posterior tibial muscle tendon adheres to the navicular bone and os tibiale externum. The os tibiale externum exists in the foot of about 15% of the healthy people and usually no symptom occurs. However, the strong transition on the posterior tibial muscle tendon by some injuries such as sprain or stress by exercise may cause pain. In case if the os tibiale externum is too large, it may cause pain due to the compression inside a shoe.

Expected Symptoms

Swelling occurs inside of the navicular bone or pain by pushing or exercising. If the os tibiale externum is too large, it can be seen as if there were two ankles on the foot and the pain can be aggravated by wearing a shoe. In addition, plantar fasciitis can be occurred together.

Frequently Caused Sports and Movements

It is seen among sports that require frequent run and jump, such as athletics, volleyball, and basketball.

Treatments and Preventions

The basic treatments to prevent aggravation of the symptom are mainly physical treatment, medical treatment, limitation on exercise, or wearing insole. Additionally, it is also important to select the best-fit footwear and fastening the shoelace for stabilizing the foot. In case of the severe condition, surgical intervention such as bone fenestration and osteosynthesis may be needed.


Footcraft showed a statistically significant arch lifting effect compared to the result without insole. There was no significant difference between Footcraft and Custom-Made insole.

Discussion by the Doctor

Insole can be roughly divided into 3 categories from its creation method.
Ready-made insole, custom-made insole mold by applying insole to each foot, and an original insole created out of each shape of foot. Although the latter two are expected to have higher effects, they take time and cost to create the insole on the other hand. Footcraft is classified as ready-made insole, but 3 arch types are prepared according to the form of the arch, so you can choose your best-fit insole for your foot. From the survey above, it is found that Footcraft provides the same level of effects on both arch support and foot alignment, comparing to custom-made insole. Unlike general ready-made insoles, it can be said that Footcraft is closer to custom-made comfort.


Kentaro HOSHIYA (Volleyball Suntory Sunbirds)

I felt that the heels were tacked in, and Footcraft fits my feet. It was a new experience, “Wow”. I guess now it is easier to carry my feet smoothly.
I did not feel much effect at the front of my feet, but I believe that the sense of fit has increased because Footcraft holds my heels firmly. I think that Footcraft helps users’ activities because it may reduce possibilities of getting fatigue and injuries with the 3 arch types that users can choose, depending on each foot condition.

Kenya FUJINAKA (Volleyball Suntory Sunbirds)

I do not like my foot sliding in the shoe. Footcraft fits securely to my heels and I got a feeling of being wrapped as if being protected.
Due to my position, I often jump, so I am impressed with the cushioning function and shock absorbing function when I land.

Yu YAMAMOTO (Volleyball Suntory Sunbirds)

I feel pain on both outside and inside of my feet, but the cushioning property of Footcraft saved me.
I think that it fits well to those with a flat foot because the arch part is solid and high. Footcraft comes with three arch types, I think that it is good that anyone can choose the best-fit one depending on your arch types.

Ayaka IKEHARA (Handball)

As my position is the wing, I feel that I am able to stand firm on the ground and jump higher with Footcraft when I shoot.
Using Footcraft with arch type LOW, I felt a great fit to my feet and I could perform with stability.

Nozomi HARA (Handball Mie Violet Iris)

(Although it is not custom-made insole) I feel a great fit. (Before I try) I underestimated….
Because I have to defend strongly holding the ground, such as when switching over from offense to defense, going to shoot after a faint, having a post in the defense, I am really impressed with the importance of shoes/insoles that matched me within such a short time.

Erena YAMANE (Handball Mie Violet Iris)

(Because it is a ready-made insole) I was concerned that it might not fit for my feet. When I actually wore it, I wondered why it fits so much.
Since I am a goal keeper, I move around more explosively. I thought that it is very good to keep the goal with the feeling of my own feet. It is a good thing to get rid of fatigue and I think you can achieve good performance during your play. I wish many people try this.