Abstract:
:This study implemented a 2-week high carbohydrate (CHO) diet intended to maximize CHO oxidation rates and examined the iron-regulatory response to a 26-km race walking effort. Twenty international-level, male race walkers were assigned to either a novel high CHO diet (MAX = 10 g/kg body mass CHO daily) inclusive of gut-training strategies, or a moderate CHO control diet (CON = 6 g/kg body mass CHO daily) for a 2-week training period. The athletes completed a 26-km race walking test protocol before and after the dietary intervention. Venous blood samples were collected pre-, post-, and 3 hr postexercise and measured for serum ferritin, interleukin-6, and hepcidin-25 concentrations. Similar decreases in serum ferritin (17-23%) occurred postintervention in MAX and CON. At the baseline, CON had a greater postexercise increase in interleukin-6 levels after 26 km of walking (20.1-fold, 95% CI [9.2, 35.7]) compared with MAX (10.2-fold, 95% CI [3.7, 18.7]). A similar finding was evident for hepcidin levels 3 hr postexercise (CON = 10.8-fold, 95% CI [4.8, 21.2]; MAX = 8.8-fold, 95% CI [3.9, 16.4]). Postintervention, there were no substantial differences in the interleukin-6 response (CON = 13.6-fold, 95% CI [9.2, 20.5]; MAX = 11.2-fold, 95% CI [6.5, 21.3]) or hepcidin levels (CON = 7.1-fold, 95% CI [2.1, 15.4]; MAX = 6.3-fold, 95% CI [1.8, 14.6]) between the dietary groups. Higher resting serum ferritin (p = .004) and hotter trial ambient temperatures (p = .014) were associated with greater hepcidin levels 3 hr postexercise. Very high CHO diets employed by endurance athletes to increase CHO oxidation have little impact on iron regulation in elite athletes. It appears that variations in serum ferritin concentration and ambient temperature, rather than dietary CHO, are associated with increased hepcidin concentrations 3 hr postexercise.
journal_name
Int J Sport Nutr Exerc Metabauthors
McKay AKA,Peeling P,Pyne DB,Tee N,Welveart M,Heikura IA,Sharma AP,Whitfield J,Ross ML,van Swelm RPL,Laarakkers CM,Burke LMdoi
10.1123/ijsnem.2020-0224subject
Has Abstractpub_date
2021-12-31 00:00:00pages
1-8eissn
1526-484Xissn
1543-2742pii
ijsnem.2020-0224pub_type
杂志文章abstract::The aim of this investigation was to determine the efficacy of a caffeine-containing energy drink to improve physical performance of elite field hockey players during a game. On 2 days separated by a week, 13 elite field hockey players (age and body mass = 23.2 ± 3.9 years and 76.1 ± 6.1 kg) ingested 3 mg of caffeine ...
journal_title:International journal of sport nutrition and exercise metabolism
pub_type: 杂志文章,随机对照试验
doi:10.1123/ijsnem.2015-0128
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abstract::To achieve the criterion appearance before competing in a physique competition, athletes undergo preparatory regimens involving high-volume intense resistance and aerobic exercise with hypocaloric energy intake. As the popularity of "drug-free" competition increases, more athletes are facing this challenge without the...
journal_title:International journal of sport nutrition and exercise metabolism
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journal_title:International journal of sport nutrition and exercise metabolism
pub_type: 临床试验,杂志文章,随机对照试验
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journal_title:International journal of sport nutrition and exercise metabolism
pub_type: 临床试验,杂志文章,随机对照试验
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journal_title:International journal of sport nutrition and exercise metabolism
pub_type: 杂志文章,评审
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journal_title:International journal of sport nutrition and exercise metabolism
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journal_title:International journal of sport nutrition and exercise metabolism
pub_type: 临床试验,杂志文章,随机对照试验
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journal_title:International journal of sport nutrition and exercise metabolism
pub_type: 杂志文章
doi:10.1123/ijsnem.2016-0239
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journal_title:International journal of sport nutrition and exercise metabolism
pub_type: 杂志文章,随机对照试验
doi:10.1123/ijsnem.2016-0325
更新日期:2017-08-01 00:00:00
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journal_title:International journal of sport nutrition and exercise metabolism
pub_type: 杂志文章
doi:10.1123/ijsnem.20.6.475
更新日期:2010-12-01 00:00:00
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journal_title:International journal of sport nutrition and exercise metabolism
pub_type: 杂志文章
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更新日期:2012-08-01 00:00:00
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journal_title:International journal of sport nutrition and exercise metabolism
pub_type: 杂志文章,随机对照试验
doi:10.1123/ijsnem.20.3.224
更新日期:2010-06-01 00:00:00
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journal_title:International journal of sport nutrition and exercise metabolism
pub_type: 杂志文章,随机对照试验
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journal_title:International journal of sport nutrition and exercise metabolism
pub_type: 杂志文章
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journal_title:International journal of sport nutrition and exercise metabolism
pub_type: 杂志文章
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journal_title:International journal of sport nutrition and exercise metabolism
pub_type: 临床试验,杂志文章
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pub_type: 杂志文章
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更新日期:2012-12-01 00:00:00
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journal_title:International journal of sport nutrition and exercise metabolism
pub_type: 杂志文章
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更新日期:2001-12-01 00:00:00
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journal_title:International journal of sport nutrition and exercise metabolism
pub_type: 杂志文章
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更新日期:2014-02-01 00:00:00
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更新日期:2009-08-01 00:00:00
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更新日期:2020-02-04 00:00:00
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journal_title:International journal of sport nutrition and exercise metabolism
pub_type: 杂志文章
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更新日期:2014-08-01 00:00:00