Biomaterial Database

Electromyographical study on muscle fatigue in repetitive forearm tasks. 2007

Wentao Dai, and Xiaorong Zhao, and Zhenglun Wang, and Lei Yang

Department of Occupational and Environmental Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China. daiwentao@yeah.net

The purpose of this study was to examine whether repetitive muscle tasks in low weight load might influence the fatigue of forearm muscles, and to identify ergonomic risk factors of forearm muscle fatigue in these tasks. Sixteen healthy male volunteers performed eight wrist extensions in different frequency, weight and angle loads while being instructed to keep a dominant upper limb posture as constant as possible. Surface electromyograph (sEMG) was recorded from right extensors digitorium (ED), flexor carpi radialis (FCR), flexor carpi ulnaris (FCU) and extensor carpi ulnaris (ECU) during the task performance. Our results showed that mean power frequency (MPF) and median frequency (MF) values of ED, FCR and FCU were significantly lower (P<0.05) at high frequency load level than at low load level. However, MPF and MF values of ED were significantly lower (P<0.01) in higher load groups of frequency, angle and weight than in lower load groups. These results indicated that the fatigue of muscles varied in the same task, and the number-one risk factor of ECU, ED and FCR was angle load.

UI	MeSH Term	Description	Entries
D008297	Male		Males
D012090	Cumulative Trauma Disorders	Harmful and painful condition caused by overuse or overexertion of some part of the musculoskeletal system, often resulting from work-related physical activities. It is characterized by inflammation, pain, or dysfunction of the involved joints, bones, ligaments, and nerves.	Overuse Syndrome,Repetition Strain Injury,Trauma Disorders, Cumulative,Injury, Repetition Strain,Overuse Injury,Repetitive Motion Disorders,Repetitive Strain Injury,Repetitive Stress Injury,Strain Injury, Repetition,Cumulative Trauma Disorder,Injury, Overuse,Injury, Repetitive Strain,Injury, Repetitive Stress,Motion Disorder, Repetitive,Overuse Injuries,Overuse Syndromes,Repetition Strain Injuries,Repetitive Motion Disorder,Repetitive Strain Injuries,Repetitive Stress Injuries,Strain Injury, Repetitive,Stress Injury, Repetitive,Trauma Disorder, Cumulative
D004576	Electromyography	Recording of the changes in electric potential of muscle by means of surface or needle electrodes.	Electromyogram,Surface Electromyography,Electromyograms,Electromyographies,Electromyographies, Surface,Electromyography, Surface,Surface Electromyographies
D005542	Forearm	Part of the upper extremity in humans and primates extending from the ELBOW to the WRIST.	Antebrachium,Antebrachiums,Forearms
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D055815	Young Adult	A person between 19 and 24 years of age.	Adult, Young,Adults, Young,Young Adults
D018482	Muscle, Skeletal	A subtype of striated muscle, attached by TENDONS to the SKELETON. Skeletal muscles are innervated and their movement can be consciously controlled. They are also called voluntary muscles.	Anterior Tibial Muscle,Gastrocnemius Muscle,Muscle, Voluntary,Plantaris Muscle,Skeletal Muscle,Soleus Muscle,Muscle, Anterior Tibial,Muscle, Gastrocnemius,Muscle, Plantaris,Muscle, Soleus,Muscles, Skeletal,Muscles, Voluntary,Skeletal Muscles,Tibial Muscle, Anterior,Voluntary Muscle,Voluntary Muscles
D018763	Muscle Fatigue	A state arrived at through prolonged and strong contraction of a muscle. Studies in athletes during prolonged submaximal exercise have shown that muscle fatigue increases in almost direct proportion to the rate of muscle glycogen depletion. Muscle fatigue in short-term maximal exercise is associated with oxygen lack and an increased level of blood and muscle lactic acid, and an accompanying increase in hydrogen-ion concentration in the exercised muscle.	Fatigue, Muscle,Muscular Fatigue,Fatigue, Muscular