1 Exercise for more than 20 minutes before you start to decompose fat. Therefore, if you want to lose weight, you should exercise for no less than 20 minutes.

This is a popular saying, in fact, this view is unconvincing. The energy supply during exercise never follows the absolute principle of either sugar or fat. The energy supply ratio of sugar and fat decomposition varies with the intensity and duration of exercise. At the beginning of low-intensity exercise, the energy supply ratio of these two substances is about 50% each. When the exercise intensity approaches the limit, the energy is mainly supplied by sugar decomposition (anaerobic metabolism). When the low-intensity exercise lasts for more than 20 minutes, the energy supply ratio of sugar decomposition still accounts for 40%, and fat accounts for 60%, which is not completely supplied by fat. Pay attention to the relationship between energy supply characteristics and diet during exercise. Studies have confirmed that the more fat you eat in your diet, the more fat you consume during exercise. Similarly, the greater the percentage of body fat, the greater the proportion of people who use fat decomposition to provide energy during exercise.

1998, British scholars Murphy and hardman reported an interesting research result: female subjects with an average age of 44.4 years old were divided into two groups, one group walked for 30 minutes continuously, and the other group divided the 30 minutes into three times, each time only walking for 10 minute, * * three times, and the total exercise time was also 30 minutes. Exercise intensity is 70%-80% of the maximum heart rate, exercise 5 times a week, * * * is 10 week. The results showed that the thickness of sebum around the body decreased, but only the weight of the group who walked for 10 minutes for 3 times decreased 1.7kg, while the weight of the group who walked for 30 minutes did not change significantly. Therefore, the idea that you can lose weight or only lose weight by continuous exercise for more than 20 minutes is denied. Of course, the total time of exercise every day should not be less than 30 minutes. At present, it is considered that as long as the exercise time is not less than 10 minute, the total exercise time of one day can be accumulated. There is no need to stick to the definition of "moderate intensity, continuous exercise for more than 30 minutes at a time" in order to be effective.

Strength exercise can increase "lean body mass", and then improve the level of basal metabolism. Because energy consumption increases at rest, the inevitable result is weight loss.

This kind of reasoning seems seamless, but so far there is no empirical research evidence to support it. According to the experimental results of 0/09 subjects in a university in the United States, the physical fitness level, that is, the maximum oxygen uptake relative to lean body weight, is highly negatively correlated with the percentage of body fat, and there is no meaningful correlation between the physical fitness level and the energy consumption during daily inactivity or sleep, that is, the percentage of body fat is not correlated with the level of quiet energy metabolism. It shows that there is no significant difference in the level of quiet energy metabolism between obese and thin people.

It is generally believed that the characteristics of individual energy supply during exercise (individual difference) are only manifested during or after a period of exercise, and there is no obvious individual difference in the process of energy supply in a quiet state.

Sharp reported in 1992 that there is an obvious linear correlation between lean body mass and quiet energy metabolism, but through calculation, it is speculated that even if a person weighing 60kg increases lean body mass by 2kg through strength exercises, the total energy consumption per day will only increase by 2%, which is much smaller than expected. In 200 1, Lemmer et al. also reported that after 24 weeks of resistance training, the lean body weight of the subjects increased by 1-2kg. Results Only the resting metabolic rate of men increased, while that of women did not change. The increased resting metabolic rate of male group is far from reaching the level of weight loss.