Help, I stepped in shit!

Review expert: Wang Linyu, deputy chief physician of the Department of Orthopedics, the Second Affiliated Hospital of Tianjin University of Traditional Chinese Medicine

Friends who like online shopping must have heard of the term "stepping on shit feeling".

Although stepping on "shit" is not a good thing, the word "stepping on shit feeling", which seems disgusting but has a mysterious sense of comfort, is often used to describe home slippers.

According to the merchant's introduction, the "shit-feeling" shoes are soft, light and springy, and feel as comfortable as stepping on naked, or even like stepping into bread.

Source: A shopping platform

Why are walking shoes so light and soft? What health risks do the "shit-like" shoes that are popular among consumers hide?

What is the “stepping on shit feeling”?

In fact, the real reason for the "stepping on shit feeling" comes from the special material used in the shoes - EVA material.

EVA, whose chemical name is ethylene-vinyl acetate copolymer , is a common product raw material obtained by copolymerization of ethylene and vinyl acetate.

Ethylene-vinyl acetate copolymer Source: Baidu Encyclopedia

Compared with the traditional shoemaking material, polyethylene , it has a lower degree of crystallinity, thus having better flexibility and impact resistance. It is often used to make slippers, foam boards, various types of luggage, etc.

In fact, the term "stepping on shit feeling" has appeared more frequently in the running shoe circle before. Compared with other shoes, the soles of this shoe are softer and have sufficient support.

Later, more and more businesses equated "feeling like stepping on shit" with "softness" and used it as a gimmick for crazy marketing. They claimed that their brand of shoes were so soft that they could be twisted into a knot without losing their shape.

However, there are huge health risks hidden behind this.

The role of shoes

If we want to understand the harm of "stepping on shit" to people, we must first analyze why people must wear shoes?

The answer is simple. The purpose of wearing shoes is to protect our feet from the external environment and avoid injury, while also keeping them warm.

Several researchers from the School of Mechanical and Vehicle Engineering of Beijing Institute of Technology conducted relevant experiments on the forces on the soles of the feet. The experiments found that when we walk, the maximum force on the soles of the feet is about 800N per step, which is even greater when running, with a maximum force of about 1400N, and can even reach more than 2000N when jumping.

Source: Zhang Chunlin, Cui Laiyou, Tan Cheng, Wang Guangquan, Kong Lingjia.

Human plantar force test and analysis. Journal of Beijing Institute of Technology

If a person walks 1000-2000 steps a day, it means that the soles of the feet have to bear 1000-2000 times of force impact every day, not to mention those friends who have WeChat steps of tens of thousands a day. Can the feet withstand such frequent pressure?

In addition, our feet have a complex tissue structure, among which the arch, Achilles tendon and plantar fascia play an important role in the weight bearing and shock absorption of the soles of the feet . But they are not absolutely omnipotent, and it is easy to get injured and have problems if you are not careful. Therefore, we need shoes to help the soles of the feet share this pressure.

Good shoes can provide good rebound and shock absorption for the feet. Rebound means providing rebound force, which helps us to be more efficient and save energy when walking, running and jumping; while shock absorption means absorbing the impact of the ground on the soles of the feet. In layman's terms, it means that the shoes are very soft to wear and can also relieve the force on the soles of the feet and provide sufficient support for the feet.

Soft shoes are hurting your feet

Regarding the "shit-feeling" shoes mentioned above, many merchants simply try to make them "softer" but fail to improve the resilience and support of the shoes at the same time , which poses many hidden dangers to the health of users.

First of all, if you wear shoes that are too soft for a long time, the pressure on the soles of your feet will not be supported and relieved for a long time, which will increase the fatigue of the soles of your feet, not to mention running and jumping.

Secondly, if the sole is too soft, the instability of the shoe increases, our control over the foot weakens, and the risk of sprains and ankles increases.

Source: CCTV.com

What’s more serious is that the soles of shoes that are too soft do not provide enough support for the soles of our feet. The arches of the feet do not get enough support, so they will easily become sore and painful after walking for a long time. In the long run, this may cause the arches of the feet to collapse and lead to flat feet.

Source: CCTV.com

Our feet are connected to our calves and knees, so injuries to the feet will affect the legs. Severe cases may even affect changes in leg shape, damage to joints, and even the lumbar spine and pelvis.

Source: CCTV.com

Therefore, choosing a pair of suitable shoes is not only important for our feet, but also for the health of the whole body. So, how do we choose a pair of shoes that suits us?

How to choose a pair of comfortable shoes

First, we need to know our arch type .

Wet your feet and step on the ground, and use the marks on the soles of your feet to determine whether you have normal feet, flat feet, or high arches .

Source: CCTV.com

For people with high arched feet , the arch is high, the sole of the foot has almost no contact with the ground, and the shock absorbing ability is poor. When choosing shoes for this type of foot, it is necessary to choose shoes with larger internal space, or choose shallow-mouthed shoes with no covering on the instep, otherwise they are easy to get stuck; you should also focus on choosing shoes with good shock absorbing ability to help the feet relieve the impact from the ground.

As for people with flat feet , unlike people with high arches, the curvature of their arches is very small and the arches are collapsed. When choosing shoes for this type of foot, people should focus on choosing shoes with better fixation and support to help strengthen the support of the feet.

For people with normal feet , it is important to choose a pair of shoes that are moderately soft and hard and of the right size.

Source: pixabay

all in all

“You can only tell whether a pair of shoes fit you by putting them on.”

Everyone's foot shape is different. No matter how exaggerated the merchants' propaganda is, you still have to try more and compare prices to choose the shoes that are truly suitable for you.

Of course, if you already feel discomfort or pain in your feet, you should go to the hospital as soon as possible.