Document Detail

Effects of altering pedal frequency on the slow component of pulmonary VO2 kinetics and EMG activity.
MedLine Citation:
PMID:  20432199     Owner:  NLM     Status:  MEDLINE    
This study investigated the effects of pedal frequency on the slow component of pulmonary oxygen uptake ( V O(2)) kinetics during heavy exercise at the same relative intensity. We hypothesized that higher pedal frequency (expected to enhance fast-twitch muscle fiber recruitment) would be associated with greater slow component amplitude (A' (s)), surface electromyography (normalized root mean square; RMS) and blood lactate concentration ([lactate]). Eight subjects performed square-wave transitions to heavy exercise at 35 and 115 rpm. Furthermore, alternated cadences square-wave transitions (35-115 rpm) were performed to examine the potential effects of additional fast-twitch muscle fiber recruitment on the slow component. Significance was accepted when P<0.05. The A' (s) was greater at higher cadences (0.58+/-0.08 and 0.70+/-0.09 L.min (-1) at 115 and 35-115 rpm, respectively) than at 35 rpm (0.35+/-0.04 L.min (-1)). Greater EMG increase over time (DeltaRMS ((10-3 min))) and [lactate] were observed at 115 and 35-115 rpm compared with 35 rpm. There was a significant correlation between A' (s) and overall DeltaRMS ((10-3 min)) for all pedal frequencies combined (r=0.63; P=0.001). Pedal frequency had no effect on time constants or time delays. These findings are consistent with the concept that progressive recruitment of muscle fibers is associated with the V O(2) slow component.
D M Hirai; B T Roseguini; F Diefenthaeler; F P Carpes; M A Vaz; E L Ferlin; J P Ribeiro; F Y Nakamura
Related Documents :
23271039 - Range of motion after total knee arthroplasty: the effect of a preoperative home exerci...
12665979 - Influence of two pedalling rate conditions on mechanical output and physiological respo...
24151589 - Effects of neuromuscular electrical stimulation combined with exercises versus an exerc...
23254489 - Effects of resistance training fatigue on joint biomechanics.
1803059 - Cardiorespiratory responses to cyclic triangular ramp forcings in work load.
17391809 - Measuring and forecasting emergency department crowding in real time.
22682689 - Are intraventricular gradients a cause of false positive treadmill exercise tests?
25144429 - Energy costs & performance of transtibial amputees & non-amputees during walking & runn...
21421819 - Hyperbaric hyperoxia reduces exercising forearm blood flow in humans.
Publication Detail:
Type:  Journal Article; Research Support, Non-U.S. Gov't     Date:  2010-04-29
Journal Detail:
Title:  International journal of sports medicine     Volume:  31     ISSN:  1439-3964     ISO Abbreviation:  Int J Sports Med     Publication Date:  2010 Aug 
Date Detail:
Created Date:  2010-07-28     Completed Date:  2010-11-08     Revised Date:  -    
Medline Journal Info:
Nlm Unique ID:  8008349     Medline TA:  Int J Sports Med     Country:  Germany    
Other Details:
Languages:  eng     Pagination:  529-36     Citation Subset:  IM    
Copyright Information:
(c) Georg Thieme Verlag KG Stuttgart . New York.
Department of Physical Education, State University of Londrina, Londrina, Brazil.
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Bicycling / physiology*
Exercise Test / methods*
Muscle Fibers, Fast-Twitch / metabolism
Muscle, Skeletal / metabolism
Oxygen Consumption*
Time Factors

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

Previous Document:  The Influence of Acute Resistance Training and Body Composition on Coagulation and Fibrinolytic Acti...
Next Document:  Finger Blood Pressure During Leg Resistance Exercise.