The first reason should be that your muscles have increased.
We all know that fat loss is systemic, and your aerobic exercise will definitely play a role in reducing fat. Because running mainly exercises the lower limbs, your body fat rate has not decreased, but your muscles have increased, which makes you feel that your legs are getting thicker and thicker, but when your body fat comes down, your legs will naturally become thinner.
Secondly, the stretching exercise is not done well.
The beautiful legs envied by many sister papers are mainly slender calves, and the underdeveloped soleus muscles of the calves will make the gastrocnemius appear bulky.
Therefore, you should fully stretch after running to make the soleus muscle slender.
The last reason is that you run too short.
Sprint will stimulate the growth of white muscle fibers, which are very thick.
However, long-distance running contributes to the growth of red muscle fibers, which are thinner in diameter, which is why long-distance runners have thinner legs than sprinters.
Running helps to improve heart and lung function, increase basal metabolic rate and help sleep. I hope everyone can stick to it!