"People who walk fast live 15 years longer than people who walk slower", can walking fast really live longer?

True points:

There is only a correlation between walking speed and longevity, and there is no causal relationship. A person's health is the real factor that affects the length of life.

Verifier: A section of Ginger 丨 Associate Professor of Research in the Department of Pathology and Experimental Medicine, University of Pennsylvania School of Medicine

Recently, there are many articles on the Internet "popular science": walking must be fast! A study in the United States found that people who walked faster lived longer than those who walked slowly, and the average life expectancy was about 15 to 20 years higher. Netizens quickly said that they need to take a big stride. "The speed of walking can determine a person's life span", is this true?

First, the study can only show that the speed of walking is related to the length of life, which does not mean that walking fast can lead to longevity

The study mentioned in the online article was published in the Mayo Clinic Journal in 2019. The study was conducted by researchers at The University of Lighthouse in the United Kingdom, which surveyed 475,000 middle-aged and elderly people in the United Kingdom, and the follow-up period was 7 years. During the follow-up period, a total of 12,823 deaths were recorded.

The researchers compared the walking habits of these 475,000 people and compared the average life expectancy of different groups at the age of 45: 86.7 to 87.8 years for women who walk fast, and 72.4 years for women who walked slowly, a difference of about 15 years; the average life expectancy of men who walked fast was 85.2 to 86.8 years, and the average life expectancy of men who walked fast was 64.8 years, a gap of more than 20 years. This is the origin of "people who walk fast live 15 to 20 years longer than people who walk slowly."

Theoretically, if all people have the same health status, but the walking speed is different, in the time frame examined, the other behaviors and environmental influences of the two groups of sho are also the same, but the final mortality rate is different, then the walking speed may indeed be the cause of the difference in mortality.

But in epidemiological investigations, it is difficult to find two people with exactly the same health status, and it is difficult to ensure that the behavior of the two groups of people is exactly the same as that affected by the environment. Therefore, for such studies, we need to carefully interpret their conclusions. In general, epidemiological studies can find a correlation between two events, but do not account for a causal relationship between the two events.

Specific to this study, the conclusion can show that there is a certain relationship between walking speed and life expectancy, but it does not mean that walking fast is the cause of longevity, let alone that as long as the walking speed is improved, life can be extended. In fact, the researchers also clearly pointed out in the paper that "as an observational study, it is impossible to infer causality."

This is like the rooster chirping and the dawn, there is a certain correlation between the two, although the rooster chirping first, the dawn is later, but it can not be said that the rooster chirping is the reason for the dawn. As we all know, the Earth rotates around the centroid of the solar system, so the circadian rhythm is the reason for the dawn.

Second, don't care too much about walking speed, the real impact on life expectancy is the health of the body

The object of the study was selected from the Uk's Biobank database. Previous studies have shown that the walking speed reported by the investigators in the UK Biobank database is closely related to their cardiorespiratory health. We all know that if a person is weak, his walking speed will be very slow.

Obesity and being too thin may indicate a person's health problems. In the study, the researchers analyzed the relationship between the respondent's obesity and life expectancy, and found that the subjects were relatively short in life, whether they were too fat or too thin. Specific to different indicators, BMI is too low, waist circumference is too long, body fat rate is too high or too low, all three of which have a very obvious correlation with short life.

It should be pointed out that for people with different walking speeds, the impact of fat and thin is not the same. For people who walk fast, the effects of being fat and thin are not very obvious; but for people who walk slowly, if they are too thin (whether it is a BMI that is too low, a waist circumference is too short, or a body fat rate is too low), the life expectancy is significantly shorter.

The authors also make it clear in the paper that the slow walking speed may be due to the fact that the respondents have infectious or chronic diseases. Faster walking speeds, especially in older people, can indicate that the body is not weak and there are no orthopedic problems. These health factors may be the ones that really affect walking speed and longevity (confounder).

In addition to obesity, the study also analyzed the grip of the hand and found that it also had a certain correlation with longevity. In fact, it can be understood that walking fast and slow, body fat and thin, and whether the hand has grip strength may be the appearance of physical health and cannot be interpreted one-sidedly. If a person cannot walk fast, is too thin or fat, or has no grip on his hands, he first needs to examine the body to rule out hidden health problems.

If the physical examination does not find obvious health problems, through proper exercise, it should be possible to prolong life. But if a person is too thin, it may be malnutrition, if you do not increase nutrition, it is useless to go too fast; if a person is too fat, especially the waist circumference is too large, if you want to live a long and healthy life, you not only need to open your legs, but also need to control your mouth, in order to improve your own health.

This article was edited by connerliu

Pay attention to [more true] to get more reliable knowledge.

Copyright Notice: This article is an exclusive manuscript of Tencent Zhenzhen, and it is forbidden to be reproduced by the media without authorization. Individuals are welcome to forward to the circle of friends.