DIFFERENCES IN ISOKINETIC KNEE AND ANKLE STRENGTH BETWEEN SUPER AND POOR BALANERS

Abstract

The 1996 Surgeon General's report emphasizes that older adults may preserve the ability to maintain independent living status and reduce the risk of falling by participating in various exercise forms. However, research results addressing the question whether individuals of superior balance skill differ from poor balancers in muscular strength remain equivocal. PURPOSE: To determine if differences existed in various isokinetic strength measures for ankle (plantar & dorsiflexion) and knee (quad & ham) total work and average power between super and poor balancers. METHODS: Subjects (N = 39) were balance tested using a dynamic balance assessment system. Super (N = 22) and poor (N = 17) balancers achieved stability index scores of 1.08 ± 0.2 and 4.42 ± 0.4, respectively. Eleven of the poor balancers were over the age of 50 yrs. After a cycle ergometer warm-up, strength testing of both legs was conducted using an isokinetic dynamometer. RESULTS: MANOVA and ANOVA analyses (P < .05) indicated significant differences between super and poor balancers for quadriceps (KEXTN) & hamstring (KFLXN) measures for total work (TW) & average power (AP) as shown below. Significant differences existed for total work and average power plantar flexion scores at 30 & 60 deg/sec, with mean ± sd scores for super and poor balancers of 116 ± 5 & 59 ± 34 ft-lbs, 110 ± 40 & 52 ± 36 ft-lbs and 19 ± 6 & 10 ± 6 W, 31 ± 11 & 15 ± 10 W, respectively. Dorsiflexion scores for total work and average power were similar between balance groups. CONCLUSION: Since the better balancers were truly stronger than their less stable counterparts, ankle and knee strength training may be an effective intervention to improve balance among older, poor balancing adults. Supported by the Biodex Medical Systems, Inc.Table: No Caption Avilable