Abstract:
:Although hyponatremia (HN) has been reported among endurance athletes, its etiology often remains uncertain and of great interest to clinicians and physiologists. This case report presents physiologic evidence regarding the etiology and development of HN during exercise in the heat. A 21-yr-old male volunteer (K.G.) unexpectedly experienced symptomatic HN during a research investigation that involved controlled sodium (Na+) intake (137 mEq Na+.d-1 for 7d) and exercise-heat acclimation (41 degrees C; 30 min.h-1, 8 h.d-1 for 10 d). Fluid balance, physiologic variables, and hematologic/hormone data were measured before and after the HN episode, with similar measurements recorded for nine unaffected volunteers. The results indicated: 1) HN was verified in K.G. (plasma Na+ < 130 mEq.l-1) after only 4 h of mild, intermittent exercise in heat; 2) K.G.'s heart rate, rectal temperature, blood pressure, and Na+ losses in sweat and urine were < or = control subjects at all times; 3) between hours 4-7, an inappropriately large release of vasopressin coincided with a decrease of urine volume to 0 ml.h-1. It was concluded that a large intake (10.3 l.7h-1) and retention (2.77 l.7h-1) of water and a "low normal" initial plasma Na+ (134 mEq.l-1) were primary factors in the development of HN in K.G., whereas Na+ losses in sweat and urine were normal and served only to exacerbate HN.
journal_name
Med Sci Sports Exercjournal_title
Medicine and science in sports and exerciseauthors
Armstrong LE,Curtis WC,Hubbard RW,Francesconi RP,Moore R,Askew EWsubject
Has Abstractpub_date
1993-05-01 00:00:00pages
543-9issue
5eissn
0195-9131issn
1530-0315journal_volume
25pub_type
杂志文章abstract:INTRODUCTION:The purpose of this study was to identify key demographic and health factors associated with physical activity (PA) participation in adults with type 1 or type 2 diabetes. METHODS:Participants were adults > or = 18 yr of age living in the province of Alberta, Canada who were previously diagnosed with type...
journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章
doi:10.1249/01.mss.0000228937.86539.95
更新日期:2006-08-01 00:00:00
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journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章
doi:10.1249/MSS.0000000000001538
更新日期:2018-06-01 00:00:00
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journal_title:Medicine and science in sports and exercise
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doi:
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journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章
doi:10.1249/MSS.0000000000001806
更新日期:2019-03-01 00:00:00
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更新日期:2016-12-01 00:00:00
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journal_title:Medicine and science in sports and exercise
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doi:
更新日期:1991-01-01 00:00:00
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journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章
doi:10.1249/MSS.0b013e3181f1bf0d
更新日期:2011-03-01 00:00:00
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journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章,评审
doi:10.1097/00005768-199806000-00010
更新日期:1998-06-01 00:00:00
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journal_title:Medicine and science in sports and exercise
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更新日期:2013-06-01 00:00:00
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journal_title:Medicine and science in sports and exercise
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更新日期:2004-08-01 00:00:00
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journal_title:Medicine and science in sports and exercise
pub_type: 临床试验,杂志文章,随机对照试验
doi:
更新日期:1991-02-01 00:00:00
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journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章
doi:10.1249/MSS.0b013e31825ab69b
更新日期:2012-10-01 00:00:00
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journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章,评审
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更新日期:2001-08-01 00:00:00
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journal_title:Medicine and science in sports and exercise
pub_type: 临床试验,杂志文章,随机对照试验
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更新日期:2002-03-01 00:00:00
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journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章,随机对照试验
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更新日期:2017-11-01 00:00:00
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journal_title:Medicine and science in sports and exercise
pub_type: 临床试验,杂志文章,随机对照试验
doi:10.1097/00005768-199604000-00009
更新日期:1996-04-01 00:00:00
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journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章
doi:10.1249/MSS.0000000000000330
更新日期:2014-11-01 00:00:00
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journal_title:Medicine and science in sports and exercise
pub_type: 临床试验,杂志文章
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更新日期:2015-05-01 00:00:00
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journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章,随机对照试验
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更新日期:2017-09-01 00:00:00
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doi:10.1249/MSS.0b013e3182300267
更新日期:2012-03-01 00:00:00
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journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章
doi:10.1249/00005768-198902000-00008
更新日期:1989-02-01 00:00:00
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journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章
doi:10.1097/00005768-199710000-00005
更新日期:1997-10-01 00:00:00
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journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章
doi:10.1097/00005768-200205000-00024
更新日期:2002-05-01 00:00:00
abstract::This study focused on age and physical activity as determinants of muscle strength. The study involved 620 women 25-73 yr of age. The five muscle groups assessed were: grip, plantarflexors, hip abductors, trunk flexors, and trunk extensors. Pearson correlations yielded significant negative correlations of muscle stren...
journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章
doi:
更新日期:1991-12-01 00:00:00
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journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章
doi:10.1097/00005768-200203000-00012
更新日期:2002-03-01 00:00:00
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journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章
doi:
更新日期:1990-06-01 00:00:00
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journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章
doi:10.1097/00005768-199803000-00014
更新日期:1998-03-01 00:00:00
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journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章
doi:
更新日期:1992-08-01 00:00:00
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journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章
doi:10.1249/00005768-199307000-00016
更新日期:1993-07-01 00:00:00
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journal_title:Medicine and science in sports and exercise
pub_type: 杂志文章
doi:10.1249/MSS.0000000000000942
更新日期:2016-08-01 00:00:00