1. Genetic factors: One or both parents have an inner personality, and children are prone to have an inner personality.
2. malnutrition: lack of nutrients such as calcium and vitamin d will affect bone development and lead to internal character.
3. Insufficient exercise: Long-term lack of exercise, especially the lack of exercise that requires feet, such as kicking the ball and skipping rope, will lead to the relaxation of the muscles and ligaments of the foot, thus affecting the normal development of the foot.
4. Inappropriate shoes: Wearing shoes that are too small or too big, or shoes with too hard or soft soles will affect the normal development of feet.
5. Incorrect posture: Maintaining an incorrect sitting posture, standing posture or walking posture for a long time will also lead to internal personality.