Document Detail

Guinea pig soleus and gastrocnemius electromyograms at varying speeds, grades, and loads.
MedLine Citation:
PMID:  7061299     Owner:  NLM     Status:  MEDLINE    
The purpose of the study was to describe changes that occur in the usage of fast-twitch and slow-twitch guinea pig hindlimb muscles, as estimated using chronically implanted electromyogram (EMG) electrodes, during voluntary locomotion under various conditions. Guinea pigs, in which fine wire electrodes were implanted in soleus (SOL) and lateral gastrocnemius (LG) muscles, were exercised at various speeds (13.4, 26.8, 40.2 m/min), grades (0-30%) and in some conditions loads (50-150 g) on a motor-driven treadmill. Bipolar EMG signals were rectified-averaged (RA-EMG) and analyzed for burst duration, amplitude, and the integral of each burst (IEMG). For each condition and muscle, total IEMG/min (IEMG/step x steps/min) was calculated and expressed as a percent of the maximum IEMG recorded. With increasing speed at 0% grade, the ratio of LG to SOL IEMG, each expressed as percent of maximum, remained constant at about 0.82. An increased stepping rate of 150 (at 13.4 m/min) to 225 (at 40.2 m/min) steps/min was accompanied by a 37% decrease in burst duration in LG and SOL. When the treadmill belt speed was increased from 13.4 to 4.02 m/min at 30% grade, the LG/SOL ratio increased from 0.83 to 1.03, whereas burst duration decreased by 49% (SOL) and 51% (LG). Soleus IEMG did not change significantly with increases in speed or grade; LG IEMG increased significantly with speed at 10% grade and with grade increase at the highest speed (40.2 m/min). These data provide some insight into how modifications of work load on a treadmill affect overall muscle activity and may assist in the interpretation of training-induced muscle biochemical alterations previously noted by other investigators.
K R Gardiner; P F Gardiner; V R Edgerton
Related Documents :
596309 - A study of exercise performance and heart rate: the response to exercise of a small gro...
10782939 - Functional electrical stimulation-assisted walking for persons with incomplete spinal i...
2777279 - Open-loop control of the freely-swinging paralyzed leg.
4030579 - Treadmill vs. floor walking: kinematics, electromyogram, and heart rate.
18976839 - Kinematic, kinetic and metabolic parameters of treadmill versus overground walking in h...
4002879 - Gait analysis after intake of increasing amounts of alcohol.
3984889 - Radionuclide assessment of ventricular contraction at rest and during exercise followin...
24633199 - Exercise pretreatment promotes mitochondrial dynamic protein opa1 expression after cere...
24933719 - How do walking, standing, and resting influence transtibial amputee residual limb fluid...
Publication Detail:
Type:  Comparative Study; Journal Article    
Journal Detail:
Title:  Journal of applied physiology: respiratory, environmental and exercise physiology     Volume:  52     ISSN:  0161-7567     ISO Abbreviation:  J Appl Physiol Respir Environ Exerc Physiol     Publication Date:  1982 Feb 
Date Detail:
Created Date:  1982-05-21     Completed Date:  1982-05-21     Revised Date:  2013-09-26    
Medline Journal Info:
Nlm Unique ID:  7801242     Medline TA:  J Appl Physiol Respir Environ Exerc Physiol     Country:  UNITED STATES    
Other Details:
Languages:  eng     Pagination:  451-7     Citation Subset:  IM; S    
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Guinea Pigs
Hindlimb / anatomy & histology
Muscles / physiology*
Physical Exertion*

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine

Previous Document:  Genioglossus muscle responses to upper airway pressure changes: afferent pathways.
Next Document:  Isotopic analysis of leucine and urea metabolism in exercising humans.