Power Versus Sarcopenia: Associations with Functionality and Physical Performance Measures

Background/ObjectiveWhile assessment of sarcopenia has drawn much attention, assessment of low muscle power has not been studied widely. This is, to a large extend, due to a more difficult assessment of power in practice. We aimed to compare the associations of low power and sarcopenia with functional and performance measures.Material and MethodsWe designed a retrospective and cross-sectional study. Community-dwelling outpatient older adults applied to a university hospital between 2012 and 2020 composed the population. We estimated body composition by bioimpedance analysis. Other measures were handgrip strength, timed-up-and-go-test (TUG), usual gait speed (UGS), activities of daily living (ADL) and instrumental activities of daily living (IADL) tests. We assessed muscle power by a practical equation using a 5-repetition sit-to-stand power test. We adjusted the power by body weight and defined low muscle power threshold as the lowest sex-specific tertile. We noted demographic characteristics, number of medications, and diseases. We defined sarcopenia by EWGSOP2 definition.ResultsCut points for low relative muscle power were <2.684 and <1.962 W/kg in males and females, respectively. Low muscle power was related with both measures of disability (impaired ADL and IADL) (OR=2.4, 95% CI= 1.4-4.0, p=0.001; OR=2.4, 95% CI= 1.4-4.1, p=0.001; respectively). Low muscle strength (i.e. probable sarcopenia) was only related with disability in IADL (OR=3.6, 95% CI= 1.6-8.; p=0.002); confirmed sarcopenia was related with neither measures. Low muscle power was not related with impaired TUG (p=1) but with impaired UGS (OR=6.6, 95% CI= 3.6-11.0; p