PMID- 17510673
OWN - NLM
STAT- MEDLINE
DCOM- 20070830
LR  - 20160513
IS  - 1715-5312 (Print)
IS  - 1715-5312 (Linking)
VI  - 32
IP  - 3
DP  - 2007 Jun
TI  - Relationship between metabolic function and skeletal muscle fatigue during a 90 s 
      maximal isometric contraction.
PG  - 394-9
AB  - Little is known concerning the contributions of oxidative phosphorylation 
      (OxPhos), anaerobic glycolytic rate (AnGly), maximum creatine kinase (CK) 
      activity, and metabolic economy (ME) on fatigue resistance. The purpose of this 
      study was to model fatigue using muscle tissue metabolic measures during a 
      maximal short-duration isometric contraction. Muscle metabolic function was 
      measured with [31P]-magnetic resonance spectroscopy (MRS) in 54 premenopausal 
      women (age: 33.8+/-6.3 y) while they performed 100% isometric plantar flexions. 
      Multiple regression analysis revealed that all metabolic variables were 
      independent predictors of fatigue resistance after adjusting for maximum 
      isometric force generated (R2=0.56). ME accounted for the largest portion (36%) 
      of overall shared variance. OxPhos accounted for the most shared variance of the 
      three energy systems. These results support previous findings that OxPhos, AnGly, 
      CK, and ME all contribute to fatigue resistance over a short duration. 
      Additionally, the continued activity of CK at the end of 90 s of maximal exercise 
      lends support to the concept of a CK shuttle facilitating energy transfer within 
      the mitochondria.
FAU - Sirikul, Bovorn
AU  - Sirikul B
AD  - Department of Kinesiology and Health Studies, Southeastern Louisiana University, 
      Hammond, LA 70402, USA. Bovorn.Sirikul@selu.edu
FAU - Hunter, Gary R
AU  - Hunter GR
FAU - Larson-Meyer, D Enette
AU  - Larson-Meyer DE
FAU - Desmond, Renee
AU  - Desmond R
FAU - Newcomer, Bradley R
AU  - Newcomer BR
LA  - eng
GR  - M01-RR-32/RR/NCRR NIH HHS/United States
GR  - R01 DK 49779-03/DK/NIDDK NIH HHS/United States
GR  - R01 DK 51684-01/DK/NIDDK NIH HHS/United States
GR  - RR 11811/RR/NCRR NIH HHS/United States
PT  - Journal Article
PT  - Research Support, N.I.H., Extramural
PT  - Research Support, Non-U.S. Gov't
PL  - Canada
TA  - Appl Physiol Nutr Metab
JT  - Applied physiology, nutrition, and metabolism = Physiologie appliquee, nutrition 
      et metabolisme
JID - 101264333
RN  - EC 2.7.3.2 (Creatine Kinase)
SB  - IM
MH  - Adult
MH  - Creatine Kinase/metabolism
MH  - Energy Metabolism
MH  - Female
MH  - Glycolysis
MH  - Humans
MH  - Isometric Contraction/*physiology
MH  - Metabolism/*physiology
MH  - Muscle Fatigue/*physiology
MH  - Muscle, Skeletal/*physiology
MH  - Oxidative Phosphorylation
EDAT- 2007/05/19 09:00
MHDA- 2007/08/31 09:00
CRDT- 2007/05/19 09:00
PHST- 2007/05/19 09:00 [pubmed]
PHST- 2007/08/31 09:00 [medline]
PHST- 2007/05/19 09:00 [entrez]
AID - h06-117 [pii]
AID - 10.1139/H06-117 [doi]
PST - ppublish
SO  - Appl Physiol Nutr Metab. 2007 Jun;32(3):394-9. doi: 10.1139/H06-117.