Perceived exertion of physical activity:: Negative association with self-rated fitness

Introduction: In epidemiological studies information on physical activity is often obtained by self-report questionnaires, assessing the type of activities performed, the absolute metabolic demand (metabolic equivalents), and the duration and frequency of the activities. As health benefits from physical activity are coupled to the relative intensity of the physical effort, we wanted to relate perceived exertion to self-reported fitness. Aim: To use a questionnaire for obtaining information on perceived exertion of physical activity in a population sample and to evaluate whether perceived exertion is associated with self-reported fitness. Methods: A total of 42 specific physical activities were included in a perceived exertion questionnaire that was sent by mail to 2,543 randomly selected men and women between 19 and 60 years of age. The participants were asked to rate activities by degree of perceived exertion on an 11-point box-scale. General linear regression analyses were undertaken with perceived exertion of the specific physical activities as outcome variables and age and self-rated fitness as determinants. Results: The response rate was 61.7% (n=1,568) and 54.3% of the respondents were women. In men and women both, the perceived exertion of 40 out of 42 specific physical activities of low, moderate, and high absolute intensity was negatively associated with self-rated fitness level. Conclusion: Perceived exertion is significantly associated with self-rated fitness level in both genders after adjustment for age. Self-rated fitness level seems to determine perception of exertion in leisure time, occupation, household, and transportation activities, whether of low, moderate, or high absolute intensity.