Mechanomyographic and electromyographic responses to eccentric and concentric isokinetic muscle actions of the biceps brachii

• Published in: Muscle & nerve 1998-11, Vol.21 (11), p.1438-1444
• Main Authors: Smith, Douglas B., Housh, Terry J., Johnson, Glen O., Evetovich, Tammy K., Ebersole, Kyle T., Perry, Sharon R.
• Format: Article
• Language: English
• Subjects: Adult; Arm - physiology; Biological and medical sciences; concentric muscle action; eccentric muscle action; Electromyography; Fundamental and applied biological sciences. Psychology; Humans; Male; mechanomyography; Movement - physiology; Muscle Contraction - physiology; Muscle, Skeletal - physiology; Space life sciences; Striated muscle. Tendons; Torque; Vertebrates: osteoarticular system, musculoskeletal system
• ISSN: 0148-639X; 1097-4598
• DOI: 10.1002/(SICI)1097-4598(199811)21:11<1438::AID-MUS11>3.0.CO;2-X

The purpose of the present investigation was to examine the effects of forearm angular velocity on the mechanomyographic (MMG) and electromyographic (EMG) responses to eccentric and concentric isokinetic muscle actions. Ten adult male volunteers (mean ± SD age = 23 ± 2 years) performed maximal eccentric and concentric muscle actions of the forearm flexors at 30°, 90°, and 150° s−1. There was no significant (P > 0.05) velocity‐related change in peak torque (PT) for the eccentric muscle actions, but there was a significant (P < 0.05) decrease in PT for the concentric muscle actions. For the eccentric and concentric muscle actions, there was a significant (P < 0.05) velocity‐related increase in MMG amplitude. There was no significant (P < 0.05) change in EMG amplitude across velocity for the eccentric or concentric muscle actions. The results indicated velocity‐related dissociations among the PT, MMG, and EMG responses to maximal eccentric and concentric isokinetic muscle actions. © 1998 John Wiley & Sons, Inc. Muscle Nerve 21: 1438–1444, 1998