Sex Differences in Barriers and Facilitators Related to Physical Activity in Adults with Knee Pain

Purpose: Improving physical activity in people with knee osteoarthritis (OA) can lead to reduced pain and improved function. Studies from the general population and from people with knee OA show that females are less active than males and are less likely to attain physical activity guidelines. To develop more effective physical activity interventions for both sexes, it is important to understand sex differences among factors related to engagement in physical activity in people with knee pain. The purpose of this study is to identify if factors that affect engagement in physical activity differ by sex. Methods: This study reports secondary analyses from a qualitative study to examine factors related to physical activity participation in adults with knee pain. Participants (n=35) with knee pain who were not meeting the 2008 physical activity guidelines participated in six focus groups (5-7 participants per group). Open ended questions regarding barriers and facilitators related to physical activity were complemented with notes on a board and handouts to aid discussion. The transcripts from the focus group meetings were audio-recorded, transcribed verbatim, and de-identified. Using a code list, developed using information from published studies, directed content analysis and line-by-line coding of the transcripts was done. Codes, categories, and subcategories related to barriers and supports to physical activity were identified. The analyses were performed using a qualitative data management software (NVIVO v11.0). For these secondary analyses, the coded data were stratified by respondent and sex to infer sex differences related to barriers and facilitators to physical activity. Results: In this cohort (age=60.9±8.6 years; BMI 28.4±4.7 kg/m2; 63% females; 31% African-Americans; 34% without an undergraduate degree; 43% with an annual income less than $50,000) weekly physical activity was 26.3±46.8 min/week and Knee injury and Osteoarthritis Outcome Score (KOOS) pain subscale was 50.3±17.3. In the primary analysis, the key domains, reflecting barriers and facilitators to physical activity, identified were physical health, psychological factors, physical environment, social environment, resources, and knowledge. Within these domains, we observed a number of differences by sex. Under “physical health”, females identified difficulty sleeping, fatigue, and body-image related to weight gain, as barriers to physical activity. Both sexes identified previous injuries or fear of injury as a barrier to physical activity, and mentioned losing weight and improving health as motivators. In general, “psychological factors” were more often a barrier to physical activity for females. Specifically, females were more likely to identify anxiety and fear (related to injuries, falls, and worsening pain), depression, boredom, and a lack of motivation, as barriers. Both sexes compared their current physical activity levels to prior levels. While males were discouraged because they couldn’t keep up with their previous sports activities, females were discouraged for not being able to keep up with a variety of activities including walking, dancing, biking, etc. Both sexes discussed challenging themselves, accepting their limitations, and gratitude as motivators. For “physical environment”, both males and females agreed that inclement weather, stairs, and public transportation were barriers whereas pleasant weather was helpful. For “social environment”, females more often identified social perception (other’s perception of them struggling or not being able to keep up) as a barrier than males, although it was mentioned by both sexes. Both sexes identified social relationships and kids as motivators. For “resources”, females more often mentioned lack of financial resources as a barrier to physical activity. Moreover, only females mentioned dietary changes to manage their symptoms. Both sexes identified volunteer work and use of assistive devices as motivators. For “knowledge”, both sexes identified challenges with implementing physical activity guidelines. The females mentioned lack of understanding related to how to exercise as a barrier, and guidance from a healthcare professional as a facilitator. On the other hand, males mentioned using mobile health technologies as a facilitator. Both sexes mentioned that incorporating physical activity into their daily routine was helpful. Conclusions: These results can be used to guide future physical activity interventions for adults with knee pain. For females, concerns regarding sleep, mood, fatigue, body-image, and knowledge of how to exercise should be addressed. For males, focus on helping them to safely improve their participation in sports-related physical activities and use of mobile health technologies should be considered. Strategies incorporating physical activity into daily routine, encouraging social networking, and helping with translating public health physical activity guidelines should be considered for all persons with knee pain.