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 study was to conduct a systematic review of the effects of probiotic supplementation on physically active individuals. The participants, interventions, comparisons, outcome and study design inclusion criteria were (a) studies involving healthy adults or older subjects of both sexes who did physical exe...
journal_title:International journal of sport nutrition and exercise metabolism
pub_type: 杂志文章
doi:10.1123/ijsnem.2018-0227
更新日期:2019-09-01 00:00:00
abstract::Opuntia ficus indica (OFI) has many physiological effects, but a relationship between OFI and heart-rate variability (HRV) has never been established. The aim of this study was to describe the effects of a diet supplement of OFI on HRV in athletes. The first day, heart rate (HR) was measured at rest in supine (SU) and...
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.18.2.169
更新日期:2008-04-01 00:00:00
abstract::The purpose of this study was to determine the effect of pre-exercise high carbohydrate meals with high glycemic index (HGI) or low glycemic index (LGI) on blood leukocyte redistribution during subsequent endurance exercise. Eight male subjects performed a 90-min run on a treadmill at 70 % VO2max 3 h after ingesting a...
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
doi:10.1123/ijsnem.14.6.647
更新日期:2004-12-01 00:00:00
abstract::This study examined the effects of carbohydrate (CHO), carbohydrate-protein (CHO+PRO), or placebo (PLA) beverages on recovery from novel eccentric exercise. Female participants performed 30 min of downhill treadmill running (-12% grade, 8.0 mph), followed by consumption of a CHO, CHO+PRO, or PLA beverage immediately, ...
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.18.1.1
更新日期:2008-02-01 00:00:00
abstract::Dietary protein intake should be optimized in all athletes to ensure proper recovery and enhance the skeletal muscle adaptive response to exercise training. In addition to total protein intake, the use of specific proteincontaining food sources and the distribution of protein throughout the day are relevant for optimi...
journal_title:International journal of sport nutrition and exercise metabolism
pub_type: 杂志文章
doi:10.1123/ijsnem.2016-0154
更新日期:2017-04-01 00:00:00
abstract::The aim of the study was to evaluate the effectiveness of an intervention program that combined nutrition education and prevention of disordered eating in a group of female professional dance students. Thirty-two dancers, aged 19-25 years, took part in the program. Evaluation was done by a series of questionnaires tha...
journal_title:International journal of sport nutrition and exercise metabolism
pub_type: 杂志文章
doi:10.1123/ijsnem.12.1.24
更新日期:2002-03-01 00:00:00
abstract:BACKGROUND:Creatine supplementation (CS) has been reported to increase body mass and improve performance in high-intensity, short-duration exercise tasks. Research on CS, most of which has come into existence since 1994, has been the focus of several qualitative reviews, but only one meta-analysis, which was conducted ...
journal_title:International journal of sport nutrition and exercise metabolism
pub_type: 杂志文章,meta分析
doi:10.1123/ijsnem.13.2.198
更新日期:2003-06-01 00:00:00
abstract::Regional fat distribution (RFD) has been associated with metabolic derangements in populations with obesity. For example, upper body fat patterning is associated with higher levels of free testosterone (FT) and lower levels of sex-hormone binding globulin (SHBG). We sought to determine the extent to which this relatio...
journal_title:International journal of sport nutrition and exercise metabolism
pub_type: 杂志文章
doi:10.1123/ijsnem.11.4.451
更新日期:2001-12-01 00:00:00
abstract::The aim of this study was to analyze the effects of 8 weeks of conjugated linoleic acid (CLA) supplementation associated with aerobic exercise on body fat and lipid profile on obese women. We performed a randomized, double-blinded and placebo-controlled trial with 28 obese women who received 3.2 g/day of CLA or 4 g/da...
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.2015-0236
更新日期:2016-04-01 00:00:00
abstract:PURPOSE:To examine how different proteins in a carbohydrate-protein beverage affect postprandial amino acid (AA), glucose, and insulin responses. METHODS:Two randomized, repeated-measures experiments were performed. In one, 10 volunteers drank 3 carbohydrate-protein beverages (380 kcal, 76 g carbohydrate, 19 g protein...
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.19.1.1
更新日期:2009-02-01 00:00:00
abstract::This experiment examined the effect of a moderate dose of caffeine on quadriceps muscle pain during a bout of high-intensity cycling in low- versus high-caffeine-consuming males. College-age men who were low (< or =100 mg/day; n = 12) or high (> or =400 mg/day; n = 13) habitual caffeine consumers ingested caffeine (5 ...
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.19.2.150
更新日期:2009-04-01 00:00:00
abstract::Hypoxic exercise is characterized by workloads decrements. Because exercise and high altitude independently elicit redox perturbations, the study purpose was to examine hypoxic and normoxic steady-state exercise on blood oxidative stress. Active males (n = 11) completed graded cycle ergometry in normoxic (975 m) and h...
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.2013-0188
更新日期:2014-12-01 00:00:00
abstract::Special operation forces participating in mountain warfare/cold weather (MWCW) training have higher energy demands, but adequate fueling is difficult to achieve. The purpose of the study was to determine energy expenditure relative to energy intake and examine fueling patterns during 3 days of MWCW training in Naval S...
journal_title:International journal of sport nutrition and exercise metabolism
pub_type: 杂志文章
doi:10.1123/ijsnem.2018-0041
更新日期:2019-05-01 00:00:00
abstract::Previous research indicates that ultramarathon exercise can result in blood oxidative stress. The purpose of this investigation was to examine the efficacy of oral supplementation with quercetin, a naturally occurring compound with known antioxidant properties, as a potential countermeasure against blood oxidative str...
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.18.6.601
更新日期:2008-12-01 00:00:00
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journal_title:International journal of sport nutrition and exercise metabolism
pub_type: 杂志文章
doi:10.1123/ijsnem.2018-0165
更新日期:2019-07-01 00:00:00
abstract::African American (AA) and European American (EA) women often exhibit differences in hemoglobin (Hb) and 25-hydroxyvitamin D [25(OH)D], both of which can be altered by calorie restriction leading to weight loss. Given these known differences, it is of clinical interest to examine the potential for race-specific, advers...
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.2016-0002
更新日期:2017-02-01 00:00:00
abstract::The term Relative Energy Deficiency in Sport was introduced by the International Olympic Committee in 2014. It refers to the potential health and performance consequences of inadequate energy for sport, emphasizing that there are consequences of low energy availability (EA; typically defined as <30 kcal·kg-1 fat-free ...
journal_title:International journal of sport nutrition and exercise metabolism
pub_type: 杂志文章,评审
doi:10.1123/ijsnem.2018-0127
更新日期:2018-07-01 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.2015-0293
更新日期:2016-10-01 00:00:00
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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
doi:10.1123/ijsnem.22.1.47
更新日期:2012-02-01 00:00:00
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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
doi:10.1123/ijsnem.13.3.294
更新日期:2003-09-01 00:00:00
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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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更新日期:2016-06-01 00:00:00
abstract:PURPOSE:This study investigated the effect of bovine colostrum (BC) on mucosal defense in the respiratory tracts of athletes and a nonexercising control group. METHODS:An athlete cohort (ATH) of 25 (12 male, 13 female) elite swimmers (age 14-23 yr) and a control cohort (CON) of 28 (9M, 19F) students (age 18-27 yr) wer...
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
abstract::The authors compared the effectiveness of daily (DAY) versus alternate day (ALT) oral iron supplementation in athletes with suboptimal iron. Endurance-trained runners (nine males and 22 females), with serum ferritin (sFer) concentrations <50 μg/L, supplemented with oral iron either DAY or ALT for 8 weeks. Serum ferrit...
journal_title:International journal of sport nutrition and exercise metabolism
pub_type: 杂志文章
doi:10.1123/ijsnem.2019-0310
更新日期:2020-03-27 00:00:00
abstract:BACKGROUND:Functional hypothalamic amenorrhea is common among female athletes and may be difficult to treat. Restoration of menses (ROM) is crucial to prevent deleterious effects to skeletal and reproductive health. OBJECTIVES:To determine the natural history of menstrual disturbances in female college athletes manage...
journal_title:International journal of sport nutrition and exercise metabolism
pub_type: 杂志文章
doi:10.1123/ijsnem.22.2.98
更新日期:2012-04-01 00:00:00
abstract::Obesity and increased arterial stiffness are independent risk factors for cardiovascular disease. Arterial stiffness is increased in obese individuals than in age-matched nonobese individuals. We demonstrated that dietary modification and exercise training are effective in reducing arterial stiffness in obese persons....
journal_title:International journal of sport nutrition and exercise metabolism
pub_type: 临床试验,杂志文章
doi:10.1123/ijsnem.2013-0107
更新日期:2015-02-01 00:00:00
abstract::This study systematically examined the influence of carbohydrate (sucrose), sodium, and caffeine on the fluid retention potential of beverages under euhydrated conditions, using the beverage hydration index method. Three cohorts, each of 12 young, healthy, active men, ingested 1 L of beverages containing four differen...
journal_title:International journal of sport nutrition and exercise metabolism
pub_type: 杂志文章
doi:10.1123/ijsnem.2018-0047
更新日期:2018-10-15 00:00:00
abstract::The aim of the present study was to investigate the effect of vitamin C with or without carbohydrate consumed acutely in beverages before and during prolonged cycling on immunoendocrine responses. In a single blind, randomized manner six healthy, moderately trained males exercised for 2.5 h at 60% VO(2max)and consumed...
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.15.5.465
更新日期:2005-10-01 00:00:00
abstract::The purpose of this study was to determine the effect of carbohydrate ingestion before and during intense constant load cycling to volitional fatigue on surface electromyographic (sEMG) activity from the vastus lateralis (VL) and vastus medialis (VM) muscles. After 24-h diet and training control, 8 well-trained subjec...
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
doi:10.1123/ijsnem.14.2.161
更新日期:2004-04-01 00:00:00
abstract::The main focus of this review is illness among elite athletes, how and why it occurs, and whether any measures can be taken to combat it or to prevent its onset. In particular, there is particular interest in exercise-induced immunodepression, which is a result of the immune system regarding exercise (e.g., prolonged,...
journal_title:International journal of sport nutrition and exercise metabolism
pub_type: 杂志文章,评审
doi:10.1123/ijsnem.2018-0288
更新日期:2019-03-01 00:00:00
abstract::Twelve healthy active subjects (6 male, 6 female) performed 60 min of exercise (60% VO(2max)) on 3 occasions after supplementing with L-Carnitine L-tartrate (LCLT) or placebo. Each subject received a chronic dose, an acute dose, and placebo in a randomized, double-blind crossover design. Dietary intake and exercise we...
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.15.4.386
更新日期:2005-08-01 00:00:00