Pathways between physical activity and quality of life in adults with multiple sclerosis.

Objective: This prospective study examined symptoms of depression, fatigue, pain, self-efficacy, and social support as possible intermediaries in the pathway between changes in physical activity and quality of life (QOL) across a 6-month period in persons with multiple sclerosis (MS). Design and Main Outcome Measures: Adults with a definite diagnosis of MS wore an accelerometer for 7 days and then completed a battery of questionnaires at baseline (n = 292) and 6-months follow-up (n = 276). The data were analyzed using panel analysis and covariance modeling in Mplus 3.0. Results: The initial analysis indicated that change in physical activity was associated with a statistically significant and small residual change in QOL (β = .07). The subsequent analysis indicated that change in physical activity was associated with residual changes in fatigue (γ = ?.17), pain (γ = ?.13), social support (γ = .07), and self-efficacy (γ = .11), and, in turn, changes in fatigue (β = ?.13), pain (β = ?.09), social support (β = .18), and self-efficacy (β = .10) were associated with a residual change in QOL. Conclusion: The observed pattern of relationships supports the possibility that physical activity is indirectly associated with improved QOL through pathways that include fatigue, pain, social support, and self-efficacy in individuals with MS. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Are physical activity and symptoms correlates of functional limitations and disability in multiple sclerosis?

Objective: This study examined physical activity and symptoms as correlates of functional limitations and disability among individuals with multiple sclerosis (MS). The authors hypothesized that physical activity and symptoms would be interrelated and that physical activity would be indirectly associated with disability through a pathway that involved functional limitations, whereas symptoms would be directly associated with both functional limitations and disability. Methods: Individuals with MS (N=133) who were recruited through a community organization wore an accelerometer for a 7-day period and completed a paper-and-pencil survey containing the Godin Leisure-Time Exercise Questionnaire (G. Godin & R. J. Shephard, 1985), Symptom Inventory (C. E. Schwartz, T. Vollmer, & H. Lee, 1999), MS-Related Symptom Checklist (E. E. Gulick, 1989), and abbreviated Late-Life Function and Disability Inventory (E. McAuley, J. F. Konopack, R. W. Motl, K. Rosengren, & K. S. Morris, 2005). The data were analyzed using structural equation modeling in AMOS 6.0. Results: The standardized coefficients indicated that (a) physical activity and symptoms were negatively correlated (Φ=-.59); (b) those who were more physically active had better function (γ=.40); (c) those with fewer symptoms had better function (γ=-.46) and less disability (γ=-.29); and (d) those with better function had less disability (β=.63). Conclusion: Findings indicate that physical activity is associated with reduced disability through a pathway that is consistent with S. Z. Nagi's disablement model in individuals with MS. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Physical activity and cognitive function in a cross-section of younger and older community-dwelling individuals.

Previous reports have indicated a small, positive relationship between physical activity and cognition. However, the majority of research has focused on older adults, with few studies examining this relationship during earlier periods of the life span. This study examined the relationship of physical activity to cognition in a cross-section of 241 community-dwelling individuals 15-71 years of age with a task requiring variable amounts of executive control. Data were analyzed with multiple regression, which controlled for age, sex, and IQ. Participants reported their physical activity behavior and were tested for reaction time (RT) and response accuracy on congruent and incongruent conditions of a flanker task, which manipulates interference control. After controlling for confounding variables, an age-related slowing of RT was observed during both congruent and incongruent flanker conditions. However, physical activity was associated with faster RT during these conditions, regardless of age. Response accuracy findings indicated that increased physical activity was associated with better performance only during the incongruent condition for the older cohort. Findings suggest that physical activity may be beneficial to both general and selective aspects of cognition, particularly among older adults. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Egress Efficacy of Persons with Multiple Sclerosis During Simulated Evacuations

Expedited evacuation of commercial and residential structures in the event of an emergency may be more difficult for persons with physical movement disorders. There is a need to better characterize the impact of such disorders and provide movement data to improve evacuee and responder safety. We undertook a pilot, feasibility study that investigated the ability of persons with multiple sclerosis (MS) and controls without MS to walk along a 48 m long path that included five different door configurations with various opening hardware and closure mechanisms, both before and after a six-minute walk, simulating a long evacuation path. Persons with MS took longer to complete the evacuation circuit (102 vs. 31 s) and to pass through each door (average 4.8 vs. 1.4 s) compared to controls. During the six-minute walk, persons with MS had decreased walking speed (0.7 vs. 1.9 m/s). The MS population demonstrated more conservative gait biomechanics throughout the simulation, i.e., wider, shorter and slower steps. Timing and biomechanical differences between populations and the potential fatigue induced through an extended evacuation can be used to improve understanding of movement in populations with disabilities, and incorporate these data into estimation of flow rates during evacuation.