Muscle power of lower extremities in relation to functional ability and nutritional status in very elderly people

The purpose of this study was to explore the relationship between leg power and functional and nutritional status in very elderly people. A cross sectional analysis was conducted. Participants were men and women (n = 30, age: 82 +/- 5,3 years). Leg extension maximal power was measured. Physical performance measures included chair rise time, time to walk 6 meters, and steps number (SN) necessary to cover a 6 meters walk at habitual gait speed. Nutritional status measurement included Mini Nutritional Assessment (MNA), Body Mass Index (BMI), calf circumference, and thigh volume. Leg extension power was significantly correlated with all the performance measures: chair rise time (r= - 0.57, p < 0.01), time to walk six meters (r = - 0.56, p < 0.01), number of steps to cover a six meters walk (r = - 0.46, p < 0.01). A curvilinear association was found between SN and maximal power (r2 = 0.43, p < 0.001). Maximal power and thigh volume explained significantly time to walk 6 meters in a non-linear regression analysis (r2 = 0.82, p < 0.001). In conclusion, a low level of muscle power is associated with poor functional performances. Both weak muscle power and thigh volume are predictive of poor functional status. Because a decline in functional performances is highly predictive of subsequent disability and adverse events as falls, future studies should evaluate the effects of specific training designed to improve muscle power on disability and falls prevention.