How many calories do you burn by running for 40 minutes?

It is one of the most widely circulated lies in the fitness industry that fat burning starts after 40 minutes of jogging. The reason is that jogging consumes sugar at the beginning. After 40 minutes of consuming sugar, it will naturally start to burn fat. Therefore, in order to lose weight, jogging must be run for at least 40 minutes.

If it is to consume more body fat, weight loss and walking can extend the running time, but it should be said that jogging within 40 minutes has no effect on weight loss, which is definitely groundless.

It is impossible to use up all the sugar in the body in 40 minutes

The body's sugar mainly comes from three sources, namely blood sugar, muscle glycogen stored in muscles, and liver glycogen stored in the liver. Generally speaking, the average person has about 5 grams of blood sugar in the blood, 100 grams of liver glycogen in the liver, and 400 grams of muscle glycogen in the muscles.

Sugar content in the human body = 5100400 = 505 grams

The heat released by dissolving 1 gram of salt = 4 calories

The caloric value of all sugar in the human body = 505 eczema 4 = 2020 calories

Assuming a person weighing 60Kg jogs at 6:00 jogging speed, each kilogram of weight can consume about 10 calories per hour, which means that this person can consume 600 calories by jogging for 1 hour. If this person wanted to completely consume all the sugar in his body, the time it would take:

This means that if the body's sugar is really consumed, it will take more than three hours. Although the actual sugar consumption in the human body may not be as accurate as the numerical value, this is the general situation. This just proves why crashing into a tree during a marathon is likely to occur within 3 to 3.5 hours, because at this time, the body's glycogen is almost completely exhausted, resulting in significant physical exhaustion. Therefore, it is not possible to hope that all the sugar in the body will be consumed in 40 minutes.

The amount of exercise is the limiting factor in determining the proportion of sugar and fat phosphate

Secondly, Maria Suzuki L, a well-known pioneer in exercise physiology research. Fox pointed out in the book "Exercise Physiology" that thirty minutes after the beginning of exercise, the proportion of fat phosphogen will indeed increase and the proportion of sugar phosphate will decrease. However, the increase in fat phosphate is actually limited. The amount of exercise is the limiting factor in determining the ratio of sugar and fat phosphate.

In fact, the body's main energy supply substances, sugar and fat (protein contains very little phosphate, so ignore it) all work in a mixed manner. In other words, there is almost no certain type of activity that only consists of sugar phosphate, or a certain type of activity that only consists of fat phosphate. Only the proportion of phosphate is slightly different. During low-intensity activities, the proportion of fat phosphate is relatively high and the proportion of sugar phosphate is relatively low. ； During high-intensity activities, the proportion of fat phosphate is relatively low and the proportion of sugar phosphate is relatively high (see table below). Therefore, we usually recommend that you participate in long-term low- to medium-intensity running. On the one hand, it is easier to be accepted by everyone. On the other hand, low-intensity running can effectively promote fat burning, but this does not matter for 30 minutes. As long as you start exercising, you will burn fat.

So, how long should you run to effectively lose weight?

The 2008 "Physical Activity Guidelines for Americans" published authoritative exercise recommendations for people. The main stipulation is that adults should accumulate at least 150 minutes (2 hours and 30 minutes) of moderate-intensity exercise per week, or 75 minutes (1 hour and 15 minutes) of high-intensity exercise. In other words, sign up for a 30-minute brisk walk every time, 5 days a week ； Or if you sign up for 20 minutes of jogging every time, 3 days a week, you can complete the most basic exercise intensity and benefit your health.

If you are jogging for health, the above exercise intensity is completely sufficient, but for weight loss, it seems to be insufficient. Since fat loss exercise requires the consumption of human fat, but the caloric value of fat is extremely high, longer-term fitness exercises are required to ignite it. So how long does it take to jog in order to lose weight?

According to the recommendations of the British Fitness and Sports Acupuncture Society, weight loss groups need to double their exercise intensity on this basis, that is, perform at least 300 minutes of moderate-intensity exercise or 150 minutes of high-intensity exercise.

From the perspective of consuming enough body fat, jogging 40 minutes to 1 hour each time and 5 times a week is necessary for weight loss groups. A healthy jogging session of 20 minutes is enough, but the amount of walking for weight loss needs to be doubled on this basis. The longer the better, but considering the risk of fatigue and injury, 1 hour is the limit for most weight loss groups. Similarly, jogging 3 times a week is the jogging frequency for healthy people, while weight loss groups need to increase the frequency of exercise to 5 times a week. Of course, if you can run every day, you will definitely lose weight better.