Which factor can reduce range of motion (ROM)?

• A. Pain, Swelling, Muscle Stiffness, Joint Effusion
• B. Regular Flexibility Training
• C. Adequate Hydration
• D. Cool Ambient Temperature

Answer: (A)

ROM is reduced when the joint and surrounding tissues are painful or mechanically restricted. Pain triggers protective muscle guarding, causing the muscles to tighten and limit movement. Swelling and joint effusion raise intra-articular pressure and create a physical block, making motion harder and less smooth. Muscle stiffness from inflammation or injury also decreases tissue compliance, so the joint can’t move as far. Regular flexibility training tends to improve ROM by lengthening and loosening tissues, rather than causing restriction. Adequate hydration supports tissue health but doesn’t directly reduce ROM, and a cool ambient temperature can make muscles feel stiffer temporarily but isn’t a primary factor in ROM limitation.