National Academy of Sports Medicine (NASM) Certified Personal Trainer (CPT) Practice Exam

What defines range of motion (ROM)?

1. The amount of strength a muscle can exert

2. The distance a joint can move without resistance or pain

3. The flexibility of surrounding muscles

4. The stability of a joint under load

The correct answer is: The distance a joint can move without resistance or pain

Range of motion (ROM) is defined as the distance a joint can move without resistance or pain. This definition encompasses the natural movement capabilities of the joint, which can be influenced by various factors such as the structure of the joint itself, the condition of the connective tissues, and overall individual flexibility. When considering this definition, it is critical to note that joint mobility is key to many physical activities and can affect overall functional movement. A joint with optimal range of motion allows for better movement patterns and can reduce the risk of injury. If a joint is restricted in its movement due to pain or resistance, it limits the effectiveness of exercises performed, which can also impact strength development and athletic performance. Other characteristics, such as muscle strength, flexibility, and joint stability, may relate to ROM indirectly, but they do not define it. Strength pertains to the maximal force a muscle can generate, flexibility refers to the extensibility of the muscles and surrounding tissues, and stability involves how well a joint can maintain its position under load. While these factors can influence a joint’s range of motion, they are distinct concepts that do not encapsulate the essence of ROM itself.