Several factors can limit joint range of motion:
Joint Structure: The shape and fit of the bones at the joint.
Ligament and Tendon Stiffness: Tightness can restrict movement.
Muscle Mass: Excessive muscle bulk can limit flexibility.
Injury or Disease: Conditions like arthritis or injuries can reduce flexibility.
Age: Flexibility tends to decrease with age.
Activity Level: Regular physical activity can maintain or improve flexibility.