"Xuong Tan Lac Than" Exercise for Range of Motion and Muscle Endurance

The goal of this clinical trial is to learn the effects of the "Xuong tan lac than" exercise on range of motion and muscle endurance in healthy volunteers. The main questions it aims to answer are: * Does practicing the "Xuong tan lac than" exercise improve joint range of motion (cervical spine, lumbar spine, shoulder, elbow, wrist, knee, and ankle)? * Does the exercise improve muscle endurance around these joints? Participants will: * Perform the "Xuong tan lac than" exercise for 12 weeks (5 days per week, once daily). * Be trained to perform the exercise correctly before starting the intervention. * Undergo assessments of joint range of motion and muscle endurance at baseline and after 2, 4, 8, and 12 weeks.