If you want to be a fitness instructor, sign up for the corresponding training course of the fitness instructor training institution. Fitness instructor training courses include some theoretical courses, such as nutrition, anatomy, physiology and so on. To master professional fitness knowledge, skills and practical experience, it is generally necessary to attend training and study in national vocational certificate examination training institutions authorized by the State Sports General Administration. Most institutions have national vocational certificate examinations every month. To be a fitness instructor, you need to master professional fitness theory and skills. Theories to be mastered: sports biomechanics, human anatomy, physiology, psychology, nutrition, etc. Skills to master: resistance training, aerobic exercise and equipment use, stretching exercise, physical training. At present, gyms are all certified.