Linked Life Data

11408419

Source:http://linkedlifedata.com/resource/pubmed/id/11408419

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
2001-6-15
pubmed:abstractText
Recently, we reported that, at similar voluntary force development during static submaximal intermittent contractions of the adductor pollicis muscle, fatigue developed more slowly in women than in men under conditions of normobaric normoxia (NN) (Acta Physiol Scand 167: 233-239, 1999). We postulated that the slower fatigue of women was due, in part, to a greater capacity for muscle oxidative phosphorylation. The present study examined whether a gender difference in adductor pollicis muscle performance also exists during acute exposure to hypobaric hypoxia (HH; 4,300-m altitude). Healthy young men (n = 12) and women (n = 21) performed repeated static contractions at 50% of maximal voluntary contraction (MVC) force of rested muscle for 5 s followed by 5 s of rest until exhaustion. MVC force was measured before and at the end of each minute of exercise and at exhaustion. Exhaustion was defined as an MVC force decline to 50% of that of rested muscle. For each gender, MVC force of rested muscle in HH was not significantly different from that in NN. MVC force tended to decline at a faster rate in HH than in NN for men but not for women. In both environments, MVC force declined faster (P < 0.01) for men than for women. For men, endurance time to exhaustion was shorter (P < 0.01) in HH than in NN [6.08 +/- 0.7 vs. 8.00 +/- 0.7 (SE) min]. However, for women, endurance time to exhaustion was similar (not significant) in HH (12.86 +/- 1.2 min) and NN (13.95 +/- 1.0 min). In both environments, endurance time to exhaustion was longer for women than for men (P < 0.01). Gender differences in the impact of HH on adductor pollicis muscle endurance persisted in a smaller number of men and women matched (n = 4 pairs) for MVC force of rested muscle and thus on submaximal absolute force and, by inference, ATP demand in both environments. In contrast to gender differences in the impact of HH on small-muscle (adductor pollicis) exercise performance, peak O(2) uptake during large-muscle exercise was lower in HH than in NN by a similar (P > 0.05) percentage for men and women (-27.6 +/- 2 and -25.1 +/- 2%, respectively). Our findings are consistent with the postulate of a higher adductor pollicis muscle oxidative capacity in women than in men and imply that isolated performance of muscle with a higher oxidative capacity may be less impaired when the muscle is exposed to HH.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jul
pubmed:issn
8750-7587
pubmed:author
pubmed:issnType
Print
pubmed:volume
91
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
100-8
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
2001
pubmed:articleTitle
Gender alters impact of hypobaric hypoxia on adductor pollicis muscle performance.
pubmed:affiliation
Thermal and Mountain Medicine Division, United States Army Research Institute of Environmental Medicine, Natick, Massachusetts 01760, USA. charles.fulco@na.amedd.army.mil
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, Non-P.H.S.