It means an "open lecture" aimed at popularizing scientific fitness knowledge and concepts, which has attracted many fitness enthusiasts to sign up. Fitness is a kind of exercise, such as all kinds of unarmed aerobics, rhythmic gymnastics, rhythmic gymnastics, and all kinds of self-resistance movements. Gymnastics and yoga can enhance strength and flexibility, increase endurance, and improve the ability to coordinate and control all parts of the body, thus making the body strong.