Abstract：
:Serum testosterone concentration was determined before and after physical activities of different duration. The subjects under study were: (1) 7 competitive walkers before and after a 20-km race (average race time 1 h 30 min); (2) 9 middle-distance runners before and after 1-h training; (3) 16 marathon runners before and after a marathon run (average running time 2 h 33 min); (4) 30 ultramarathon runners before and after a 107-km race (average running time 14 h). Serum testosterone increased by 51.8% (NS) in competitive walkers, by 38.2% (P less than 0.05) in middle-distance runners, and by 44.9% (P less than 0.01) in marathon runners; it decreased by 31.9% (P less than 0.001) in the ultramarathon runners. These findings, and similar variations of serum testosterone observed in an ultramarathon runner during a 6-h training session, suggest that serum testosterone increases during physical activities lasting up to 3 h and decreases to or even below the pre-exercise values for longer physical efforts. The possible mechanisms responsible for these differences are discussed.
journal_name
Int J Sports Medjournal_title
International journal of sports medicineauthors
Guglielmini C,Paolini AR,Conconi Fdoi
10.1055/s-2008-1025914subject
Has Abstractpub_date
1984-10-01 00:00:00pages
246-9issue
5eissn
0172-4622issn
1439-3964journal_volume
5pub_type
杂志文章abstract：:The purpose of this study was to establish the content validity of the Rodeo SCAT for the sport of rodeo and bull riding. The study design was comprised of expert consensus and content validation. A modified Ebel procedure was employed to content validate the rodeo SCAT. Content validation using this method includes e...
journal_title：International journal of sports medicine
pub_type： 共识发展会议,杂志文章
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journal_title：International journal of sports medicine
pub_type： 杂志文章
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journal_title：International journal of sports medicine
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journal_title：International journal of sports medicine
pub_type： 杂志文章
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journal_title：International journal of sports medicine
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journal_title：International journal of sports medicine
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journal_title：International journal of sports medicine
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journal_title：International journal of sports medicine
pub_type： 杂志文章,评审
doi：10.1055/s-2007-1024592
更新日期：1992-10-01 00:00:00
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pub_type： 杂志文章
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journal_title：International journal of sports medicine
pub_type： 杂志文章
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更新日期：2007-05-01 00:00:00
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journal_title：International journal of sports medicine
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更新日期：2009-10-01 00:00:00
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pub_type： 杂志文章
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更新日期：2020-08-01 00:00:00
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pub_type： 临床试验,杂志文章
doi：10.1055/s-2002-35532
更新日期：2002-11-01 00:00:00
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journal_title：International journal of sports medicine
pub_type： 杂志文章
doi：10.1055/s-2007-1024923
更新日期：1989-10-01 00:00:00
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journal_title：International journal of sports medicine
pub_type： 杂志文章
doi：
更新日期：1989-06-01 00:00:00
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journal_title：International journal of sports medicine
pub_type： 杂志文章
doi：10.1055/s-2007-973033
更新日期：1995-10-01 00:00:00
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journal_title：International journal of sports medicine
pub_type： 杂志文章
doi：10.1055/s-2001-11345
更新日期：2001-02-01 00:00:00
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journal_title：International journal of sports medicine
pub_type： 杂志文章
doi：10.1055/s-2007-1021290
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journal_title：International journal of sports medicine
pub_type： 杂志文章,随机对照试验
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journal_title：International journal of sports medicine
pub_type： 临床试验,杂志文章,随机对照试验
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pub_type： 临床试验,杂志文章
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更新日期：1985-06-01 00:00:00
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pub_type： 杂志文章
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pub_type： 杂志文章
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pub_type： 杂志文章
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journal_title：International journal of sports medicine
pub_type： 杂志文章
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journal_title：International journal of sports medicine
pub_type： 杂志文章
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更新日期：1996-04-01 00:00:00
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journal_title：International journal of sports medicine
pub_type： 杂志文章
doi：10.1055/s-2007-1024774
更新日期：1990-04-01 00:00:00
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journal_title：International journal of sports medicine
pub_type： 杂志文章
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更新日期：2013-03-01 00:00:00
