Isokinetic strength benefits after 24 weeks of multicomponent exercise training and combined exercise training in older adults

Abstract

Studies that have attempted to address the influence of exercise programs on muscle strength have usually analyzed single exercise training types. They have not often addressed multicomponent exercise interventions that combine strength, flexibility, balance and aerobic training. The aim of the present study was to assess and compare improvements in muscle strength induced by 24 weeks of two training regimens in elderly adults aged 65-82 years. Participants underwent a multicomponent exercise program (ME, n=25, 69.4+/-4.1 yrs) or combined ME plus resistance training (CE, n=24, 68.7+/-4.2 yrs). Maximum strength of knee extensors (KE) and flexors (KF) was measured at 60 masculine/s and 180 masculine/s with an isokinetic dynamometer before and 12 and 24 weeks after the training programs. The CE group showed a significant increase in maximum voluntary knee extensors (22.3%, p<0.001) and knee flexors (29.6%, p<0.001) at 180 masculine/s in the non-dominant leg, in knee extensor torque at 60 masculine/s in the dominant (6.7%, p=0.023) and non-dominant leg (17.3%, p<0.001) and in knee flexor torque at 60 masculine/s in dominant (16.4%, p=0.020) and non-dominant leg (24.2%, p<0.001). No significant changes were observed in the ME group after 24 weeks of training. The present study indicates that twice-weekly ME has a limited effect on isokinetic muscle strength. Our results also emphasize that adding moderate intensity resistance exercise twice a week to a ME protocol is sufficient to induce higher and significant strength improvements in healthy older subjects.