What Is an Insole? Put Your Foot Into Shoes That Fit Perfectly

What is an Insole?

I think most people think of insoles as the removable sole inside their shoes.

That is exactly right!

But, what is their function and why do we need it inside our shoes?

Let’s take a look today.

The Role of Insoles

The insoles that you put into your shoes have various roles.

However, they can be loosely divided into three main reasons:

  1. Pressure distribution

Simply put, it is a state in which pressure is evenly applied to the entire sole of the foot.

By creating this state, the burden on the sole of the foot is reduced and it becomes less tiring.

Specifically, it plays the role of distributing pressure by supporting the three arches on the sole of the foot.

Are there calluses or blisters on the soles of your feet?

This is usually caused by pressure being concentrated on one place on the sole of the foot.

In such cases, it is necessary to make fine adjustments to the insole so that the affected area is not burdened.

  1. Adjust the distortion of the foot

The insole can also play a corrective role when the structure of the foot is deformed.

By supporting the foot’s structure from the soles of the feet, it also has the role of reducing pain in the knees and lower back and improving the strain of the body.

The insole kind of acts like a “cane” that supports the sole of the foot.

  1. Improve sports performance

Sport insoles play various functions depending on the event.

The role of the insole differs depending on the purpose, such as increasing speed, or jumping power.

It absorbs the impact of the foot, increasing the speed, and so on.

It depends on the type of exercise, such as body movements and how the muscles are used.

Insole That Supports the Foot’s Arch

It is no exaggeration to say that the burden on the soles of human feet is supported by three main locations:

1. The base of the toes, 

2. The base of the little toe

3. The heel 

The line connecting the big toe and the little toe is called the "horizontal arch”.

The line connecting the little toe to the heel is called the "outer vertical arch”.

The line connecting the big toe to the heel is called the "inner vertical arch”.

The arch connecting these three points is the "sole arch". 

Optimal Shape of the Sole Arch

The healthy "three-point sole arch" creates a “bow-like” shape when drawn. 

The rest of the foot itself acts like a “cushion”.

The cushions on the soles of the feet distribute the strain on the toes and heels, reducing the fatigue and pain in the legs. 

The two main roles of the insole are:

1. Size adjustment of large shoes; and 

2. Correction of an abnormally-shaped sole arch

I Want to Get Rid of Shoes That Don't Fit With an Insole

If you wear shoes that don't fit your feet, whether they are too large or too tight, your feet will get tired within a few hours. 

Forcing yourself to put up with the pain can cause the deformation of the sole arch", which can lead to pain in the heels and toes, and serious problems such as hallux valgus, varus valgus, and flat feet.

Do you need insoles in the first place?

There’s no straight “yes” or “no” answer.

Because it depends on the purpose and application.

In the first place, the insole is easy to adjust according to your foot.

So if you don't need it, you don't really have to have it.

The comfort of shoes is not determined only by the insoles.

Even shoes without insoles are easy to wear because the shoes and insoles are integrated.

On the other hand, if comfort is important to you, shoes with insoles are recommended.

Of course, adjustments are possible without an insole, but with one, the range of adjustments is wider.

Therefore, it is easy to deal with any inconvenience while wearing it.

If there is a shoe store that measures your feet and adjusts them to suit your feet, you should inquire there.

If possible, avoid replacing the insoles yourself or adjusting with commercially available parts.

It may not be as effective as you would expect.

Foot Problems of Modern Humans

Unlike in the past, modern people do not walk barefoot on uneven areas like gravel roads full or pebbles and small stones. 

Abnormalities and degeneration of the soles of the feet causes problems like hallux valgus and secondary flat feet.

Flat Feet

Did you know, we are not born with the arch in our feet?

This is formed gradually by walking.

It is formed around the age of eight, and when the arch is not formed after that, it is generally called flat feet. 

The arch of the foot acts like a spring that supports the weight and absorbs impact. 

However, because the arch disappears and the feet becomes flat, the impact when the weight is applied to the feet cannot be absorbed well.

This can cause fatigue and pain in the soles, feet, calves and thighs when standing or walking for a long time.

Hallux valgus

Hallux valgus is a state in which the toe is bent towards the little toe. 

This is usually a result of wearing tight footwear too often. 

Depending on the symptom, you may feel pain every time you walk or even stand up.

The protruding part may hit your shoes and cause pain or swelling.


Fatigue is the most common cause of tired feet. 

The feet are located farthest from the heart, and even under normal conditions, blood circulation is likely to be impaired and fatigue substances are likely to accumulate. 

On top of that, if you use the muscle too often, it will harden and further reduce the ability to circulate blood.

This causes an accumulation of fatigue. 

In severe cases, the legs may have internal bleeding and red spots may spread.

Plantar Fasciitis

Plantar fasciitis is a disease in which the tendon and plantar fasciitis becomes inflames which causes small tears and pain.

The plantar fasciitis stretches like a membrane from the base of the toes to the heel. 

When the vertical arch collapses and the plantar aponeurosis is excessively stretched and flattened, plantar fasciitis occurs, and the plantar aponeurosis becomes difficult to stretch and becomes like an old rubber that is easily cut.

How to Choose the Right Insoles

The use of insoles is effective as a countermeasure for symptoms such as flat feet, hallux valgus, fatigue, and plantar fasciitis, which are problems of the feet that modern people have. 

Here, I will introduce the role played by insoles:

There are three important points which will help you choose the perfect insole. 

  1. Purpose of Using Insoles

Insoles are roughly divided into those for correcting foot distortion and those for sports. 

Choose an insole depending on which purpose you use it for.

  1. Types of shoes

What you choose depends on the type of shoes, such as whether you use them with leather shoes or heels. 

What is an Insole Made Out Of?


Insoles made of urethane or sponge have cushioning properties to reduce foot fatigue, but they tend to get stuffy when there is excessive sweating or when it rains. 

There is also an insole for cold weather in the winter. 

This type of insole is often used for sneakers and athletic shoes.


Insoles made of polyester is often used for size adjustment.


Insoles crafted from wool is mainly used for cold weather. 

They keep your feet warm but can easily cause stuffiness.


It's hard to get stuffy, it's easy to absorb sweat, and it emphasizes comfort, but there are few stores that sell it or the price is high. It is often used for leather shoes, boots, and high heels.

Activated carbon

It is not as stuffy as leather, but it is intended to absorb sweat. Some have been enhanced by using silver or mesh.

Choosing the Perfect Insole

For example, shoes for hiking, sports, travel, pumps with heels, shoes for standing work, etc., there are various purposes and designs for wearing shoes.

There are also insoles that have been treated with antibacterial and deodorant functions that have a deodorant function, and insoles that have been developed for medical purposes such as for plantar fasciitis. 


Often insoles are overlooked, but they serve many useful functions. 

When deciding on which insole to choose, ask yourself this question: “What is the purpose of wearing shoes and foot problems that you want to improve most now?


Leave a comment

Please note, comments must be approved before they are published