MUSCLE STRENGTH AND FUNCTIONAL MOBILITY IN RELATION TO LEAN BODY-MASSIN FREE-LIVING FRAIL ELDERLY WOMEN

Objectives: (1) To describe body composition of the frail elderly, (2) To relate lean body mass to muscle strength and functional ability, a nd (3) To assess temporal stability of strength measures and index of functional ability. Design: Cross-sectional study. Setting: Community- dwelling. Subjects: Thirty frail elderly women (81.5 +/- 7 y) recruite d from residences or out-patient facilities. Methods: Total body fat a nd fat-free mass (FFM) were determined using multi-frequency bioelectr ical impedance analysis and predicted from anthropometry. Handgrip str ength, biceps and quadriceps strength, functional capacities (Timed '' Up & Go'') as well as self-perceived health and functional status were measured. Reliability was assessed using two separate observations ma de one week apart by the same examiner. Results: Mean height, weight a nd body mass index were 1.52 +/- 0.04 m, 60.4 +/- 10.7 kg and 26.0 +/- 4.8 kg/m(2) respectively. FFM (34.1 +/- 4.6 kg) was lower than previo us reports for autonomous elderly females and associated with all meas ures of muscle strength (Pearson's r= 0.42-0.62 p less than or equal t o 0.02), but not with performance on the Timed ''Up & Go'' or self-per ceived health and functional status. Strength measures correlated sign ificantly with different subscales of self-perceived functional capaci ties and were significantly lower among women with a low %FFM (n = 19) and those reporting pain (n = 11) as compared to other women. Excelle nt temporal stability for muscle and functional measures was observed (ICC = 0.80-0.90). Conclusions: Muscle strength was strongly related t o FFM in free-living frail elderly women especially in the absence of pain.