Musculoskeletal Fitness for Identifying Low Physical Function in Older Women

Abstract

Aims: This cross-sectional study aimed to analyze the relevance of musculoskeletal fitness for identifying low physical functioning in community-dwelling older women. Methods: Sixty-six older women (73.62 ± 8.23 yrs old) performed a musculoskeletal fitness assessment of the upper and lower limbs. A handheld dynamometer was used to evaluate upper-limb muscle strength through a handgrip (HG) test. Lower-limb power and force were assessed from a two-leg countermovement vertical jump (VJ) on a ground reaction force platform. Physical functioning was assessed subjectively using the Composite Physical Function (CPF) questionnaire and objectively by daily step count measured by accelerometry and gait speed/agility assessed by the 8-Foot Up-and-Go (TUG) test. Logistic regressions and ROC curves were carried out, aiming to define odds ratios and ideal cutoff values for discriminatory variables. Results: VJ power showed the ability to identify low physical functioning when evaluated through the CPF (14 W/kg, 1011 W), gait speed/agility (15 W/kg, 800 W), or daily accumulated steps (17 W/kg). Considering that VJ power was normalized for body mass, the increase of 1 W/kg corresponds to a decrease of 21%, 19%, or 16% in the chance of low physical functioning when expressed by these variables, respectively. HG strength and VJ force did not show a capacity to identify low physical functioning. Conclusions: The results suggest that VJ power is the only marker of low physical functioning when considering the three benchmarks: perception of physical ability, capacity for mobility, and daily mobility.

Functionality, muscular strength and cardiorespiratory capacity in the elderly: relationships between functional and physical tests according to sex and age

“…On the other hand, the CMJ exhibited more significant correlations with functional and cardiorespiratory tests. Previous studies have observed significant correlations between relative power and maximum vertical jump velocity ( Parsons et al, 2020 ; Abreu et al, 2023 ). Similar to the current study, previous work by Winger et al reported that relative power in vertical jump and speed at maximum power showed associations twice as strong compared to HG strength ( Winger et al, 2020 ).…”

“…Concerning TUG, consistent with our study, it correlated significantly with squats, walking speed, SPPB, and the 30-s sit-to-stand test ( Santos et al, 2022 ), exhibiting higher correlations compared to HG ( Staples et al, 2020 ). Several studies emphasize that lower limb muscle power might be a more relevant marker for aging compared to HG and muscle mass ( Runge et al, 2004 ; Parsons et al, 2020 ; Abreu et al, 2023 ). Power and speed could be more crucial factors in preventing functional loss in older individuals compared to muscle strength ( Winger et al, 2020 ).…”

“…Therefore, fitness assessment is becoming increasingly common ( Cruz-Jentoft et al, 2010 ). The ability to maintain high levels of functioning in old age has been linked to the preservation of skeletal muscle function ( Abreu et al, 2023 ). Decreased muscle strength and aerobic capacity is associated with decreased functional capacity and independence ( Cruz-Jentoft et al, 2010 ).…”

“…Studies analyzing relationships between physical and functional tests in an elderly population have previously been published ( Singh et al, 2014 ; Orssatto et al, 2020 ; Parsons et al, 2020 ; Staples et al, 2020 ; Santos et al, 2022 ; Abreu et al, 2023 ). However, few studies differentiate between sexes and age ranges ( Buehring et al, 2015 ; Okabe et al, 2021 ; Monjo et al, 2023 ).…”

“…However, information on the influence of sex and age is still scarce. On the other hand, it is known that power and muscle strength are related to measures of muscle function assessed by test batteries such as the SPPB ( Parsons et al, 2020 ; Abreu et al, 2023 ). However, these relationships might be different between sexes and ages due to differences in muscle degeneration.…”