The reason for this is the following：
1, the difference between male and female hormones is dozens of times, so even if women and men do strength training, it is difficult to build strong muscles.
2. Spinning is an endurance sport, and endurance sports can't train big muscles. For example, in favorite running (especially long-distance running) or riding, slow muscle fibers will gradually increase, but the main force of muscle increase-fast muscle fibers will not increase significantly, or even shrink.
3. Some people think that cycling will make legs thicker, but in fact, for most women with thick legs, it is mostly caused by fat accumulation. Even if you are a mixture of muscle and fat, proper running or riding training can reduce fat and improve the calf line.
4. Some people have the illusion that their legs are getting thicker and thicker because they have not lost a lot of fat in their legs, but they have seen the slow muscles from jogging when their legs are hard. You should know that muscles are everyone's (you can't stand without them, and your figure will be ugly). It's just different sizes. No matter who you are, when you push hard, your muscles will be more developed and obvious. And regular jogging exercise is not conducive to muscle development.