Neuromuscular adaptation to early post-operative, high-intensity, short resistance training of non-operated lower extremity in elderly patients: A randomized controlled trial

Abstract

Objective: To evaluate the short-term effects of high-intensity, task-specific vs regular rehabilitation programme on neuromuscular activity and functional changes in elderly inpatients. Design: Single-blind, randomized controlled trial. Patients: Sixty-two patients, aged 74.1 (standard deviation (SD) 6.9) years, 12.8 (SD 3.6) days after operation of one lower limb. Methods: Allocation to either high- or regular-intensity strength training of non-operated limb, of 3 weeks duration. Outcome measurements: ratio of integrated electromyography per weight lifted (mm vastus medialis and lateralis), isometric electromyography (EMG), maximal weight lifted expressed as 1 repetition maximum, torque in Nm and isometric maximal force of uninvolved leg, timed "up and go" test (TUG) and Western Ontario and McMaster Universities (WOMAC) questionnaire. Results: Both programmes resulted in significant improvements in: integrated EMG/weight lifted ratio, isometric EMG, 1 repetition maximum, torque and isometric force, TUG performance and WOMAC items (all p < 0.0001, Wilcoxon signed-rank test). Significant differences were found between the high- and regular-intensity groups for integrated EMG/weight lifted (p = 0.026), 1 repetition maximum and torque (p = 0.0014, Wilcoxon rank-sum test). Conclusion: High-intensity, short-period, early postoperative muscle training has a superior effect on maximal weight lifted by the knee extensors and integrated EMG/weight lifted compared with regular training. These findings are in accordance with more rapid neuronal adaptation by a high-intensity rehabilitation programme. © 2007 Foundation of Rehabilitation Information.