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Methods to Quantify Pharmacologically Induced Alterations in Motor Function in Human Incomplete SCI
Published on: April 18, 2011
Adaptive changes in motor control of rhythmic movement after maximal eccentric actions
Reijo Bottas1, Caroline Nicol, Paavo V Komi
1University of Jyväskylä, Neuromuscular Research Center, Department of Biology of Physical Activity, PO Box 35, 40014 Jyväskylä, Finland. reijo.bottas@sport.jyu.fi
Summary
Exhaustive eccentric exercise impairs motor control and muscle function for over 7 days. The neuromuscular system compensates by optimizing muscle coordination, potentially through nerve ending sensitization.
Area of Science:
- Exercise Physiology
- Neuromuscular Function
- Muscle Physiology
Background:
- Eccentric exercise (EE) can induce significant muscle damage and alter motor control.
- Understanding the long-term effects of exhaustive EE on motor performance is crucial for rehabilitation and training.
Purpose of the Study:
- To examine the effects of exhaustive eccentric exercise on the motor control of rhythmic elbow movements.
- To investigate the recovery of dynamic force production and neuromuscular activity after exhaustive EE.
Main Methods:
- Eight male students performed 100 maximal eccentric actions of elbow flexor muscles.
- Maximal isokinetic tests and a rhythmic movement (RM) test were conducted pre- and post-exercise (0.5h, 2 days, 7 days).
- Surface electromyography (EMG) of biceps brachii (BB) and triceps brachii (TB) was recorded, along with serum creatine kinase (CK) levels.
Main Results:
- Dynamic force production significantly decreased post-EE and did not fully recover within 7 days.
- Delayed onset of muscle soreness (DOMS) and elevated CK activity indicated muscle damage.
- Rhythmic movement velocity was preserved despite increased EMG in the fatigued biceps brachii, suggesting compensatory mechanisms.
Conclusions:
- The neuromuscular system can compensate for eccentric-induced contractile failure by enhancing antagonistic muscle coordination.
- Recovery from exhaustive EE is prolonged, with potential compensatory mechanisms involving muscle nerve endings sensitization.
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