There is a need to provide and utilize consistent definitions for accurate understanding, proper evaluation and communication of physical activity, exercise, and sedentary behaviors among persons with multiple sclerosis (MS), according to a recent study. 53 persons with MS who were enrolled in an exercise trial took part in semi-structured interviews regarding personal interpretations of physical activity, exercise, and sedentary behaviors. Researchers found:

• 43% of participants indicated a consistent understanding of physical activity, 42% of participants indicated a consistent understanding of exercise, and 83% of participants indicated a consistent understanding of sedentary behavior with the standard definitions.
• There was evidence of definitional ambiguity (ie, 57, 58, and 11% of the sample for physical activity, exercise, and sedentary behavior, respectively); 6% of the sample inconsistently defined sedentary behavior with standard definitions.
• Some participants described physical activity in a manner that more closely aligned with exercise and confused sedentary behavior with exercise or sleeping/napping.