Associations of distinct levels of physical activity with mobility in independent healthy older women.

Background: Older adults have twice as many disabilities and four times as many physical limitations as people <60 years of age. Positive influence of physical activity to prevent these limitations has been presented in some studies. However, the indispensable combination of physical abilities and body composition parameters to maintain independence in later life and their relationship with physical activity has not been studied thoroughly.

Objective: The main aim of this study was to determine possible differences in body composition and mobility parameters among older women with various levels of engagement in physical activity. In addition, the relationships between mobility and distinct levels of physical activity were evaluated in healthy older women.

Methods: Eighty-one healthy older women aged from 65 to 91 years participated in this study and were allocated to three groups according to weekly moderate-to-vigorous physical activity (MVPA) time in 10 min bouts: highest MVPA (H-MVPA) (n = 27), middle MVPA (M-MVPA) (n = 40) and lowest MVPA (L-MVPA) (n = 14). Body composition (fat mass [FM] and fat free mass [FFM]) variables were assessed with dual-energy X-ray absorptiometry (DXA), objective physical activity data were collected with accelerometers and mobility tests were carried out to assess static and dynamic balance, lower limbs strength and aerobic capacity.

Results: No differences in body composition parameters were observed between studied groups (p > 0.0025). Women in L-MVPA covered significantly shorter distance during the six-minute walk test (6MWT) compared to H-MVPA (p = 0.000) and M-MVPA (p = 0.003) groups, performed timed-up-and-go (TUG) slower compared to H-MVPA group (p = 0.003) and five-times-sit-to-stand (FTSTS) test slower compared to H-MVPA (p = 0.006) and M-MVPA (p = 0.009) groups. There were no differences in body composition and mobility parameters between women in H-MVPA and M-MVPA groups. Regardless of bout duration, MVPA was correlated with mobility (TUG r = -0.47; FTSTS r = -0.37; 6MWT r = 0.53) parameters, whereas no relationships was observed with light physical activity (LPA).

Conclusion: MVPA is associated with body composition and mobility parameters, while LPA is not related to any measured body composition nor mobility parameters. Accordingly, healthy older women could benefit from MVPA to maintain body composition and mobility parameters to preserve independence in later life.