Investigating Aging-Related Changes in the Coordination of Agonist and Antagonist Muscles Using Fuzzy Entropy and Mutual Information
Open Access
Abstract
Aging alters muscular coordination patterns. This study aimed to investigate aging-related changes in the coordination of agonist and antagonist muscles from two aspects, the activities of individual muscles and the inter-muscular coupling. Eighteen young subjects and 10 elderly subjects were recruited to modulate the agonist muscle activity to track a target during voluntary isometric elbow flexion and extension. Normalized muscle activation and fuzzy entropy (FuzzyEn) were applied to depict the activities of biceps and triceps. Mutual information (MI) was utilized to measure the inter-muscular coupling between biceps and triceps. The agonist activation decreased and the antagonist activation increased significantly during elbow flexion and extension with aging. FuzzyEn values of agonist electromyogram (EMG) were similar between the two age groups. FuzzyEn values of antagonist EMG increased significantly with aging during elbow extension. MI decreased significantly with aging during elbow extension. These results indicated increased antagonist co-activation and decreased inter-muscular coupling with aging during elbow extension, which might result from the reduced reciprocal inhibition and the recruitment of additional cortical-spinal pathways connected to biceps. Based on FuzzyEn and MI, this study provided a comprehensive understanding of the mechanisms underlying the aging-related changes in the coordination of agonist and antagonist muscles.Keywords
Funding Information
- National Natural Science Foundation of China (61273359, 91520201)
This publication has 38 references indexed in Scilit:
- Changes in the spatio‐temporal organization of the trapezius muscle activity in response to eccentric contractionsScandinavian Journal of Medicine & Science in Sports, 2011
- Age-related differences in pre-movement antagonist muscle co-activation and reaction-time performanceExperimental Gerontology, 2011
- How should we normalize electromyograms obtained from healthy participants? What we have learned from over 25years of researchJournal of Electromyography and Kinesiology, 2010
- Linear and nonlinear information flow based on time-delayed mutual information method and its application to corticomuscular interactionClinical Neurophysiology, 2010
- Dynamics and stability of muscle activations during walking in healthy young and older adultsJournal of Biomechanics, 2009
- Transcranial direct current stimulation of the primary motor cortex affects cortical drive to human musculature as assessed by intermuscular coherenceThe Journal of Physiology, 2006
- Mechanisms Responsible for the Age-Associated Increase in Coactivation of Antagonist MusclesExercise and Sport Sciences Reviews, 2006
- Spinal excitation and inhibition decrease as humans ageCanadian Journal of Physiology and Pharmacology, 2004
- The influence of ageing on the force–velocity–power characteristics of human elbow flexor musclesExperimental Gerontology, 2003
- Estimation of mutual information using kernel density estimatorsPhysical Review E, 1995