Hello, the principle of losing weight is to control calorie intake less than consumption. This formula determines whether we can lose weight. In addition, the exercise you mentioned, running for 30-40 minutes every day, belongs to pure aerobic training. We should be clear that in order to achieve good fat-reducing effect, pure aerobic training is not enough. On the contrary, doing aerobic training for too long will lead to the decline of our metabolic level, so you should cooperate with the corresponding strength, so that the fat-reducing effect will be good.