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Updated: Jul 11, 2026

Improving Strength, Power, Muscle Aerobic Capacity, and Glucose Tolerance through Short-term Progressive Strength Training Among Elderly People
Published on: July 5, 2017
Changes in antagonist muscles' coactivation in response to strength training in older women
Maarten D de Boer1, Christopher I Morse, Jeanette M Thom
1Institute for Biophysical and Clinical Research into Human Movement, Manchester Metropolitan University, Alsager, ST7 2HL, United Kingdom.
Background:
The purpose of this study was to assess changes in neuromuscular function of the plantarflexor and dorsiflexor muscles after 1 year of strength training of these muscles in elderly women. Twelve participants were assigned to a training (74.2 +/- 3.1 years) group and eight to a nontraining group (73.6 +/- 4.3 years).
Methods:
Isometric maximum voluntary contractions (MVC) and muscle activation based on surface electromyography (EMG) were recorded before and after the 12-month training program at six different joint angles.
Results:
After training (in the training group), (a) plantarflexion (PF) MVC increased on average by 14.4% (p <.05) across ankle joint angles from -20 degrees dorsiflexion (DF) to +30 degrees PF, (b) DF MVC decreased by 5.7% (p <.05), (c) PF EMG root mean square increased on average by 22.3% (p <.05), and (d) PF antagonists' coactivation increased on average by 7.5% across the tested joint angles. No changes were observed in the nontraining group.
Conclusions:
The present results show a significant increase in antagonist muscle coactivation with strength training in older women. The hypothesis is put forward that with a training-induced gain in agonist muscles' torque, stabilization of the ankle joint by increasing antagonist coactivation is needed because of a changed ratio of maximal PF torque to maximal DF torque.
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