Body composition, muscle strength and quality of active elderly women according to the distance covered in the 6-minute walk test

BACKGROUND: Changes arising from the aging process, particularly changes in body composition, contribute to the functional decline of the elderly. OBJECTIVE: To compare the body composition and muscle strength, mobility and quality in active elderly women according to the distance walked during the 6-minute walk test (6MWT). METHOD: The study included 77 active elderly women aged 65 to 80 years, who were divided into tertiles (A, B and C) according to the distance covered in the 6MWT. We performed anthropometric and clinical evaluations. Body composition was determined by dual energy X-ray absorptiometry (DXA). Handgrip strength (HGS) was measured with a portable dynamometer (Saehan), and knee extension strength (KES) was measured with the one repetition maximum test (1-RM). Functional mobility was assessed by the Timed Up and Go (TUG) test, and body balance was assessed by the Berg Balance Scale (BBS). Muscle quality was defined by the ratio between muscle strength (kgf) and muscle mass (kg). RESULTS: The group that walked the shortest distance in the 6MWT had a higher BMI (A=30.8±7.0, B=27.2±4.2 and C=25.9±3.5 kg/m2), greater amount of fat mass (A=31.3±10.7, B=25.9±6.7 and C=23.81±6.46 kg) lower HGS (A=21.8±5.1, B=22.1±3.5 and C=25.5±5.1 kgf), lower knee extension strength (A=30.6±10.9, B=40.4±12.5 and C=47.2±10.1 kgf), lower arm muscle quality (A=10.1±3.7, B=11.6±2 and C=12.7±2.2 kg) and lower leg muscle quality (A=1.78±1, B=2.84±0.98 and C=3.31±0.77 kg). There was no significant difference between muscle mass (p=0.25) and lean mass (p=0.26). CONCLUSION: Body fat has a negative influence on functional performance, even among active elderly women. .

Comparação da oscilação postural estática na posição sentada entre jovens e idosos saudáveis / Comparing static sitting postural sway of healthy young and older adults

OBJETIVOS: Descrever uma nova metodologia de análise da oscilação postural estática sentada e comparar os resultados de jovens e idosos saudáveis. MÉTODOS: Participaram do estudo 38 indivíduos saudáveis, 17 jovens (idade média 23±2,38 anos) e 21 idosos (idade média 67±2,42 anos). A oscilação postural foi mensurada por meio do sistema eletromagnético Polhemus® 3Space Isotrack II. As avaliações foram feitas nas condições olhos abertos (OA) e fechados (OF), com os voluntários sentados sem apoio plantar e sem encosto em suportes de madeira (superfície estável-SE) e de espuma (superfície instável-SI). Cada condição sensorial foi avaliada durante 90 segundos. Os parâmetros analisados foram: deslocamento máximo (Dmáx), trajetória total (Traj) e velocidade média (Vel) nos planos sagital (X) e frontal (Y). RESULTADOS: Nas condições OA e OF em SE, foram encontradas oscilações nos planos X e Y dos parâmetros Traj e Vel maiores em jovens que em idosos. Em SI, foram observadas maiores Traj Y e Vel Y nos jovens, sem diferença significativa entre os grupos quanto a Traj X e Vel X com olhos fechados. Em relação ao Dmáx, tanto no plano X quanto no Y, em todas as condições sensoriais, só houve diferença significativa na condição OASE no plano sagital, sendo maior nos jovens. CONCLUSÕES: Jovens saudáveis oscilam mais que os idosos saudáveis na posição sentada. Além disso, a ferramenta utilizada mostrou ser útil para análise da oscilação postural estática na posição sentada, possibilitando o surgimento de estudos que a associem com o efeito de diversas tarefas motoras.

OBJECTIVES: To describe a new method to analyze the static sitting postural sway and to compare the results of healthy young and older adult subjects. METHODS: Thirty-eight healthy subjects took part in the study, including 17 young adults (mean age 23±2.38 years old) and 21 older adults (mean age 67±2.42 years old). The device used to quantify trunk sway was the magnetic field sensor Polhemus® 3Space Isotrack II. The measurements were taken in the eyes-opened (EO) and eyes-closed (EC) condition with the subjects seated first on a wooden stable surface (SS) then on a foam unstable surface (US) without back or foot support. Each sensory condition was assessed for 90 seconds. The analyzed parameters were: maximum amplitude (Amp), total trajectory (Traj) and mean velocity (Vel) in the sagittal (X) and frontal (Y) planes. RESULTS: In the EO and EC conditions on SS, young adults presented greater postural sway in the X and Y planes on the Traj and Vel parameters. In the US, young adults showed greater Y Traj and Y Vel in the EO and EC conditions, and there was no significant difference between the groups with regard to X Traj and X Vel in the EC condition. The young adults presented greater Amp only in the EOSS condition in the X plane. CONCLUSIONS: The young adult subjects presented greater sway in the sitting position than the older adult subjects. In addition, the Polhemus® device was a useful tool to analyze static sitting postural sway and can be used in future studies that associate static sitting postural sway with the effect of various motor tasks.