When summer comes, flip flops have become a must-have item for trendy men and women. Together with shorts, they have a proper street style. However, no matter how comfortable the flip-flop is, it can’t be worn for a long time, otherwise it will cause a variety of injuries to our lower limbs. Don’t believe it, there is research to prove this fact.
I. research related to flip flops
Auburn University in the United States has done a research related to wearing flip flops. Under the chairmanship of Wendy Weimar, an associate professor of biomechanics, students of the Department of biomechanics established a research group on flip flops. Thirty nine volunteers, male and female, aged between 19 and 25 years, participated in the experiment, and none of them had a history of lower limb injury.
In the experiment, volunteers will wear running shoes and flip flops to walk. In order to make the data as objective as possible, the flip flops provided in the experiment came from different manufacturers and retailers, and the prices ranged from $5 to $50. The materials and comfort levels also varied. Similarly, running shoes have many different prices and designs.
Volunteers participating in the experiment will attach sensors to their backs, hips, calves, ankles and feet. There is a platform on the ground. When you step on it, the vertical force data of the foot will be recorded at the moment when the foot contacts the surface of the platform. At the same time, the movement posture of the subjects when walking, and any subtle movements of their hips, legs, ankles, feet and toes were recorded by the video system.
The final experimental report points out that when people wear flip flops, they walk with shorter strides. The same distance requires more steps, which leads to more pressure on the body, which means more wear and tear on muscles and joints.
II. Foot injuries caused by flip flops
Compared with stiletto heels, the pain caused by flip flops is slow and not obvious, and the hidden harm is even more terrible.
1. Cause chronic ankle injury
Mike O’Neill, spokesman of the British Association of foot care and podiatrists, said that people wearing flip flops land on the outside of the soles of their feet, and then turn their feet inward, transferring the pressure to their big toes. This repeated twisting action brings pressure to the ankle, which may cause chronic injury in the long run. When the ankle becomes fragile, it is easy to sprain, and once sprained, it will cause frequent sprains.
2. Inflammation of plantar fascia
In normal gait, when a person steps off the ground, the minimum value of the maximum ankle dorsiflexion angle is 10 °, if it is less than 10 °, it will lead to a compensatory turnover of the foot, which will increase the tensile load of the plantar fascia. In the above tests, when the volunteers walked with slippers, the maximum dorsiflexion angle of the ankle joint was less than 10 °. Therefore, if they wore flip flops for a long time, it was inevitable that plantar fasciitis or other foot discomfort would be caused due to excessive tensile load of plantar fascia.
3. Causing multiple pain in lower limbs
When wearing flip flops, in order not to drop the shoes, the stride will be automatically shortened, and the ankles will turn inward, which will form the “inner splay”, and the inner splay will cause too much stress on the knees, resulting in knee joint strain. In addition, when walking, a person’s center of gravity will tilt forward, his knees will naturally bend slightly, and his lumbar spine will bend backward. As time goes on, his hip joint and lumbar spine will be painful. Flip flops lack support for the feet, which will also cause arch and tendon pain, and may also cause calf pain.
4. The foot is more vulnerable to trauma.
In the UK, more than 200000 people seek treatment for falls or chronic foot injuries caused by wearing flip flops every year. The annual expenditure of the British health department on treating injuries caused by flip flops is 40 million pounds. Flip flops actually make your feet more vulnerable to trauma. For example, if you walk on an uneven road, you will be sprained and bruised carelessly; Walking in the grass will be stabbed and cut by flowers and plants; And in crowded places, they also face the risk of being trampled; wait.
5. Severe leg deformation in many places
① The legs are bent. Flat bottom flip flops can hardly provide any support for the feet. The ankles must turn inward to better apply force and walk. The calves are forced to expand outward, which will lead to the appearance of inner eight, and it will be difficult to correct the leg shape for a long time.
② Toe variant. When walking in flip flops, the toes will bend and “hook” the slippers. The muscle contraction of the toes at each step is contrary to normal physiological behavior, which is easy to lead to big toe deformity.
③ The deformation of the soles of the feet is normal. The soles of our feet have a certain curvature, which can play a buffering role. If we wear flat flip flops for too long, the gap between the five toes will become larger, and the soles of our feet will sink to form flat feet.
6. Provide a living environment for bacteria
A study by the University of Miami in the United States once said that flip flops carried as many as 18000 bacteria, and 13900 bacteria after entering and leaving public toilets. These bacteria include Staphylococcus (a deadly bacterium), Escherichia coli and even some fecal bacteria. In summer, when the heels are dry, the plastic soles of flip flops rub against the soles of the feet and all minor wounds and cracks, which provides an ideal breeding environment for a large number of bacteria. However, most flip flops require less cleaning times, and the presence of these bacteria will affect your health.
7. It is easy to cause traffic accidents.
A survey found that nearly 1.4 million road traffic accidents or dangers were caused by drivers wearing flip flops every year. On the question of whether to consider the impact of shoes on driving safety, only 14% of drivers will give up driving because their shoes are unsafe. Many people only consider whether it is beautiful, not safety. Even 10% of women admit that they will drive in shoes that even make it difficult to walk. However, this will easily lead to traffic accidents.
Generally speaking, flip flops are not impossible to wear, but you should appropriately change into other comfortable shoes to recover from the damage caused by flip flops.