A study on the relationship between muscle function, functional mobility and level of physical activity in community-dwelling elderly

Objectives: to evaluate the relationship between lower extremity muscle function, calf circumference (CC), handgrip strength (HG), functional mobility and level of physical activity among age groups (65-69, 70-79, 80+) of older adults (men and women) and to identify the best parameter for screening muscle function loss in the elderly. Methods: 81 community-dwelling elderly (42 women and 39 men) participated. Walking speed (Multisprint Kit), HG (Jamar dynamometer), hip, knee and ankle muscle function (Biodex isokinetic dynamometer), level of physical activity (Human Activity Profile) and CC (tape measure) were evaluated. ANOVA, Pearson correlation and ROC curves were used for statistical analysis. Results: Dominant CC (34.9 +/- 3 vs 37.7 +/- 3.6), habitual (1.1 +/- 0.2 vs 1.2 +/- 0.2) and fast (1.4 +/- 0.3 vs 1.7 +/- 0.3) walking speed, HG (23.8 +/- 7.5 vs 31.8 +/- 10.3), average peak torque and average hip, knee and ankle power (p< 0.05) were lower for the 80+ group than for the 65-69 year-olds. There were no differences in physical activity level among age groups. Moderate significant correlations were found between muscle function parameters, walking speed and HG; a fair degree of relationship was found between muscle function parameters, CC and level of physical activity (p< 0.05). The ROC curve analysis suggested a cutoff point of 14.51 Kgf for screening muscle function loss in elderly women (p= 0.03). Conclusions: This study demonstrated an association between muscle function, HG and fast walking speed, a decrease in these parameters with age and the possibility of using HG to screen for muscle function of the lower extremities.