Yes, fitness and muscle building can increase the body's muscle content, thus increasing strength, but it is not easy. First, the subjects need anaerobic training, and the amount and intensity of training should reach the goal. The subject is mainly to carefully record the daily completion with a small notebook. If the next training is completed, the intensity should be increased. Secondly, protein should be supplemented on the day of training to ensure the intake of other carbohydrates and fats. Finally, to ensure the quality of sleep, it is necessary to reach the rest time. If all these questions meet the requirements, then you can effectively gain muscles and thus increase your strength.