Abstract：
:The use of dietary supplements is widespread in sport and most athletes competing at the highest level of competition use some form of dietary supplementation. Many of these supplements confer no performance or health benefit, and some may actually be detrimental to both performance and health when taken in high doses for prolonged periods. Some supplements contain excessive doses of potentially toxic ingredients, while others do not contain significant amounts of the ingredients listed on the label. There is also now evidence that some of the apparently legitimate dietary supplements on sale contain ingredients that are not declared on the label but that are prohibited by the doping regulations of the International Olympic Committee and of the World Anti-Doping Agency. Contaminants that have been identified include a variety of anabolic androgenic steroids (including testosterone and nandrolone as well as the pro-hormones of these compounds), ephedrine and caffeine. This contamination may in most cases be the result of poor manufacturing practice, but there is some evidence of deliberate adulteration of products. The principle of strict liability that applies in sport means that innocent ingestion of prohibited substances is not an acceptable excuse, and athletes testing positive are liable to penalties. Although it is undoubtedly the case that some athletes are guilty of deliberate cheating, some positive tests are likely to be the result of inadvertent ingestion of prohibited substances present in otherwise innocuous dietary supplements.
journal_name
J Sports Scijournal_title
Journal of sports sciencesauthors
Maughan RJdoi
10.1080/02640410400023258subject
Has Abstractpub_date
2005-09-01 00:00:00pages
883-9issue
9eissn
0264-0414issn
1466-447Xpii
V221285782WR5N22journal_volume
23pub_type
杂志文章,评审abstract：:The optimum pre-flight characteristics of the Hecht and handspring somersault vaults were determined using a two-segment simulation model. The model consisted of an arm segment and a body segment connected by a frictionless pin joint, simulating the vault from the Reuther board take-off through to landing. During hors...
journal_title：Journal of sports sciences
pub_type： 杂志文章
doi：10.1080/026404199366028
更新日期：1999-04-01 00:00:00
abstract：:The aim of this study was to compare equivalence and agreement of physical activity output data collected by a Research Tri-axial accelerometer (R3T) during walking and running on a treadmill versus on land. Fifty healthy volunteers, 35 males (age 21.9 +/- 1.8 years) and 15 females (age 21.6 +/- 0.7 years), underwent ...
journal_title：Journal of sports sciences
pub_type： 杂志文章
doi：10.1080/02640410802680580
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abstract：:To develop and assess the validity of the Referee Training Activity Questionnaire (RTAQ), a systematic process was employed: 1) item generation; 2) assessments of content and face validity; and 3) assessments of criterion validity. In stage 1, items were generated following semi-structured interviews with an expert pa...
journal_title：Journal of sports sciences
pub_type： 杂志文章
doi：10.1080/02640414.2020.1800371
更新日期：2020-12-01 00:00:00
abstract：:The Drinkwater-Ross anthropometric fractionation of body mass (mass = sigma skeletal, residual, fat and muscle masses), lean body mass (LBM = sigma skeletal, residual and muscle masses) and fat mass (FM) were compared with the measured body mass, together with the densitometrically estimated fat-free mass (FFM) and fa...
journal_title：Journal of sports sciences
pub_type： 杂志文章
doi：10.1080/02640419108729891
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abstract：:The use of high-resolution physical activity intensity spectra obtained from accelerometry can improve knowledge of associations with health and development beyond the use of traditional summary measures of intensity. The aim of the present study was to compare three different approaches for determining associations f...
journal_title：Journal of sports sciences
pub_type： 杂志文章
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更新日期：2020-09-20 00:00:00
abstract：:The aim of this study was to examine shock attenuation before and after completing a maximal effort graded exercise test while running on a treadmill. Ten individuals ran before and after a maximal graded exercise test with running speed controlled between conditions. Transfer functions were calculated using surface-m...
journal_title：Journal of sports sciences
pub_type： 杂志文章
doi：10.1080/0264041031000140383
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journal_title：Journal of sports sciences
pub_type： 杂志文章
doi：10.1080/02640414.2015.1093649
更新日期：2016-01-01 00:00:00
abstract：:This study examined if short-duration record power outputs can be predicted with the Anaerobic Power Reserve (APR) model in professional cyclists using a field-based approach. Additionally, we evaluated if modified model parameters could improve predictive ability of the model. Twelve professional cyclists (V̇O2max 75...
journal_title：Journal of sports sciences
pub_type： 杂志文章
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更新日期：2019-03-01 00:00:00
abstract：:The human spleen shows a decrease in volume of around 40% early during vigorous exercise and in response to other stressful stimuli such as maximal apnoea and the breathing of hypoxic gas mixtures. Contraction seems an active response, mediated by alpha-adrenergic fibres in the splenic nerve. Given the relatively smal...
journal_title：Journal of sports sciences
pub_type： 杂志文章,评审
doi：10.1080/02640414.2015.1078488
更新日期：2016-01-01 00:00:00
abstract：:The purpose of this study was to investigate the influence of shaft stiffness on grip and clubhead kinematics. Two driver shafts with disparate levels of stiffness, but very similar inertial properties, were tested by 33 golfers representing a range of abilities. Shaft deflection data as well as grip and clubhead kine...
journal_title：Journal of sports sciences
pub_type： 杂志文章
doi：10.1080/02640414.2016.1157262
更新日期：2017-01-01 00:00:00
abstract：:Resistance training is a commonly used strategy for improving both athletic performance and general health. While the contribution of resistance training intensity and volume to muscle strength and hypertrophy have been extensively investigated, training frequency only recently received sufficient attention, especiall...
journal_title：Journal of sports sciences
pub_type： 杂志文章
doi：10.1080/02640414.2020.1822595
更新日期：2021-02-01 00:00:00
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journal_title：Journal of sports sciences
pub_type： 杂志文章
doi：10.1080/026404198366786
更新日期：1998-04-01 00:00:00
abstract：:The causes of fatigue during muscular exercise include factors that reside in the brain (central mechanisms) as well as the muscles themselves (peripheral mechanisms). Central fatigue is largely unexplored, but there is increasing evidence that increased brain serotonin (5-HT) can lead to central (mental) fatigue, the...
journal_title：Journal of sports sciences
pub_type： 杂志文章,评审
doi：10.1080/02640419508732277
更新日期：1995-07-01 00:00:00
abstract：:This study investigated the effect of self-reported tolerance of the intensity of exercise on affective responses to, self-efficacy for and intention to repeat low-volume high-intensity interval exercise (HIIE). Thirty-six healthy participants (mean age 21 ± 2 years) were split into high tolerance (HT; n = 19), low to...
journal_title：Journal of sports sciences
pub_type： 杂志文章
doi：10.1080/02640414.2019.1570590
更新日期：2019-07-01 00:00:00
abstract：:This study aimed to assess the effects of post-activation potentiation in the strength related variables of a kick start. Thirteen competitive swimmers performed three kick starts after a standardized warm up (denoted USUAL) and another after inducing post-activation through five isotonic repetitions on an eccentric f...
journal_title：Journal of sports sciences
pub_type： 杂志文章
doi：10.1080/02640414.2018.1505183
更新日期：2019-02-01 00:00:00
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journal_title：Journal of sports sciences
pub_type： 杂志文章
doi：10.1080/026404101300149393
更新日期：2001-06-01 00:00:00
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journal_title：Journal of sports sciences
pub_type： 杂志文章
doi：10.1080/02640414.2012.754924
更新日期：2013-01-01 00:00:00
abstract：:Body image is an important concept when assessing mental health and, thus, a target for intervention work. The common approach to assess body image is via self-report and, consequently, it is important to assess stability and susceptibility of items to random change. Participants (N = 99, aged: 18-30 years) completed ...
journal_title：Journal of sports sciences
pub_type： 杂志文章
doi：10.1080/02640414.2015.1018930
更新日期：2015-01-01 00:00:00
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journal_title：Journal of sports sciences
pub_type： 杂志文章
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更新日期：2008-08-01 00:00:00
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journal_title：Journal of sports sciences
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更新日期：2009-03-01 00:00:00
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journal_title：Journal of sports sciences
pub_type： 杂志文章
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更新日期：2000-09-01 00:00:00
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journal_title：Journal of sports sciences
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更新日期：2011-12-01 00:00:00
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journal_title：Journal of sports sciences
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更新日期：2020-01-01 00:00:00
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journal_title：Journal of sports sciences
pub_type： 杂志文章,meta分析
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更新日期：2020-05-01 00:00:00
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journal_title：Journal of sports sciences
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更新日期：2019-04-01 00:00:00
abstract：:The yips is considered a task-specific movement disorder. Its estimated prevalence, however, is high compared to similar neurological movement disorders, possibly resulting from previous studies' restriction of samples based on skill level, and self-report bias. Alternatively, this high prevalence might be an indicati...
journal_title：Journal of sports sciences
pub_type： 杂志文章
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更新日期：2015-01-01 00:00:00
abstract：:The present retrospective study intended to determine age, performance, the role of nationality and participation trends across calendar years in runners competing in "Comrades Marathon", the ultra-marathon with the longest tradition and the highest number of finishers worldwide. We analysed 235,467 finishers (40,211 ...
journal_title：Journal of sports sciences
pub_type： 杂志文章
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更新日期：2019-06-01 00:00:00
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journal_title：Journal of sports sciences
pub_type： 杂志文章,随机对照试验
doi：10.1080/02640414.2018.1504602
更新日期：2019-02-01 00:00:00
abstract：:The cognitive effects of acute aerobic exercise were investigated in endurance-trained individuals. On two occasions, 21 cyclists; 11 male (VO2max: 57 ± 9 mL·kg-1·min-1) and 10 female (VO2max: 51 ± 9 mL·kg-1·min-1), completed 45 min of fixed, moderate-intensity (discontinuous) cycling followed by an incremental ride t...
journal_title：Journal of sports sciences
pub_type： 杂志文章
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更新日期：2021-01-01 00:00:00
abstract：:This study aimed to evaluate the autonomic modulation of heart rate in sedentary paraplegics and paraplegic wheelchair basketball players with thoracic spinal cord injury below T6. Seven paraplegic wheelchair basketball players (active paraplegic group), five paraplegics who were not involved in regular exercise (sede...
journal_title：Journal of sports sciences
pub_type： 杂志文章
doi：10.1080/02640414.2012.734917
更新日期：2013-01-01 00:00:00
