Document Detail


Dynamic characteristics of heart-rate responses to sine-function work-load patterns in man.
MedLine Citation:
PMID:  1171433     Owner:  NLM     Status:  MEDLINE    
Abstract/OtherAbstract:
Dynamic characteristics of heart rate in response to sinusoidal variations of work load were analysed in 8 male and 3 female untrained students exercising in a sitting position on a bicycle ergometer. The mean work load was 90 watt in men and 60 watt in women, the amplitudes being 50 and 30 watt respectively. Nine different frequencies were used, the periods varying from 0.5 to 15.0 min. By means of harmonic analysis, the fundamental components in the response of the heart rate have been shown to prevail over the 2nd and 3rd harmonics, indicating a mainly linear behaviour of the control system in the work-load range studied. A comparison of the frequency response of untrained males and females observed in this study and of trained sportsmen, investigated by wigertz (1970), reveals differences between the groups. The individual and ensemble mean frequency responses have been described by several transfer functions, the best fit having been obtained with functions containing two time constants including one with a highly damped oscillating element. The dominating dynamic parameter is a time constant of about 20 to 30 sec. This time constant tends to be shorter and its portion of the frequency response diminishes in order from the untrained females and males to the trained sportsmen. The individual time constant decreases as the PWC170 increases, and is therefore a suitable criterion for estimating the physical performance of individuals under dynamic conditions.
Authors:
N Tiedt; B Wohlgemuth; P Wohlgemuth
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Publication Detail:
Type:  Journal Article    
Journal Detail:
Title:  Pflügers Archiv : European journal of physiology     Volume:  355     ISSN:  0031-6768     ISO Abbreviation:  Pflugers Arch.     Publication Date:  1975  
Date Detail:
Created Date:  1975-11-07     Completed Date:  1975-11-07     Revised Date:  2008-11-21    
Medline Journal Info:
Nlm Unique ID:  0154720     Medline TA:  Pflugers Arch     Country:  GERMANY, WEST    
Other Details:
Languages:  eng     Pagination:  175-87     Citation Subset:  IM    
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MeSH Terms
Descriptor/Qualifier:
Adult
Feedback
Female
Heart Rate*
Humans
Male
Physical Exertion*
Physical Fitness
Systems Analysis

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


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