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 small size of the human spleen, the effect upon physical performance is likely to be small; the augmentation of total blood volume is <2%, and even taking account of other causes of haemoconcentration during vigorous exercise, the increase of haematocrit is <10%. However, one of two studies suggested that the haemoconcentration may be sufficient to cause errors in the traditional method for calculating exercise-induced changes of plasma volume. The spleen also contributes leucocytes and platelets to the general circulation as part of the "fight or flight" reaction to stressors. The mobilisation of leucocytes proceeds more slowly than that of the red cells; it depends not only upon an active contraction of the spleen, but also a modulation of leucocyte adhesion molecules. Splenectomy impairs exercise performance in horses, but human performance data are lacking; overall health effects seem minimal, and many patients live many years after removal of their spleens.
journal_name
J Sports Scijournal_title
Journal of sports sciencesauthors
Shephard RJdoi
10.1080/02640414.2015.1078488subject
Has Abstractpub_date
2016-01-01 00:00:00pages
929-36issue
10eissn
0264-0414issn
1466-447Xjournal_volume
34pub_type
杂志文章,评审abstract：:Previous research on unstable footwear has suggested that it may induce mechanical noise during walking. The purpose of this study was to explore whether unstable footwear could be considered as a noise-based training gear to exercise body center of mass (CoM) motion during walking. Ground reaction forces were collect...
journal_title：Journal of sports sciences
pub_type： 杂志文章
doi：10.1080/02640414.2018.1474726
更新日期：2018-12-01 00:00:00
abstract：:Free radical production increases during exercise and oxidative damage occurs in several tissues. We examined the effects of three different exercise tests on the pattern of change of erythrocyte enzyme antioxidant activities. The tests were a short maximal exercise test, a submaximal prolonged exercise test and a cyc...
journal_title：Journal of sports sciences
pub_type： 杂志文章
doi：10.1080/02640410410001716724
更新日期：2005-01-01 00:00:00
abstract：:Muscle strength is thought to be a major factor in athletic success. However, the relationship between muscle strength and sprint performance has received little attention. The aim of this study was to examine the relationship in elite performers of isokinetic muscle strength across three lower limb joints and sprinti...
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：: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：:This study investigated the effects of two different doses of caffeine on endurance cycle time trial performance in male athletes. Using a randomised, placebo-controlled, double-blind crossover study design, sixteen well-trained and familiarised male cyclists (Mean ± s: Age = 32.6 ± 8.3 years; Body mass = 78.5 ± 6.0 k...
journal_title：Journal of sports sciences
pub_type： 杂志文章,随机对照试验
doi：10.1080/02640414.2011.632431
更新日期：2012-01-01 00:00:00
abstract：:To determine the effect of circadian rhythm on neuromuscular responses and kinematics related to physical tennis performance, after a standardised warm-up, 13 highly competitive male tennis players were tested twice for serve velocity/accuracy (SVA), countermovement vertical jump (CMJ), isometric handgrip strength (IS...
journal_title：Journal of sports sciences
pub_type： 杂志文章,随机对照试验
doi：10.1080/02640414.2016.1258481
更新日期：2017-11-01 00:00:00
abstract：:The presence of the relative age effect (RAE) has been widely reported; however, its underlying causes have not yet been determined. With this in mind, the present study examined if anthropometry and performance were different amongst older and younger soccer players born in the same year. Eighty-eight young soccer pl...
journal_title：Journal of sports sciences
pub_type： 杂志文章
doi：10.1080/02640414.2013.832355
更新日期：2014-01-01 00:00:00
abstract：:The main purposes of this study were to investigate the acute effects of static and dynamic lower limb stretching routines: (a) on peak torque, total external work and joint angle at peak torque of the hamstrings during maximal eccentric isokinetic leg flexion; (b) on unilateral hamstring to quadriceps (H/Q) strength ...
journal_title：Journal of sports sciences
pub_type： 杂志文章,随机对照试验
doi：10.1080/02640414.2012.751119
更新日期：2013-01-01 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
abstract：:Recreational tennis players tend to have higher incidence of tennis elbow, and this has been hypothesised to be related to one-handed backhand technique and off-centre ball impacts on the racket face. This study aimed to investigate for a range of participants the effect of off-longitudinal axis and off-lateral axis b...
journal_title：Journal of sports sciences
pub_type： 杂志文章
doi：10.1080/02640414.2016.1211308
更新日期：2017-07-01 00:00:00
abstract：:The purpose of this study was to explore elite coaches' perceptions of how they can both facilitate and impede the development of key mental toughness characteristics in the context of Australian football. Eleven coaches from a previous study (Gucciardi, Gordon, & Dimmock, 2008) were re-interviewed and the transcribed...
journal_title：Journal of sports sciences
pub_type： 杂志文章
doi：10.1080/02640410903150475
更新日期：2009-11-01 00:00:00
abstract：:This study examined the effect of wearing time on comfort perception and landing biomechanics of basketball shoes with different midsole hardness. Fifteen basketball players performed drop landing and layup first step while wearing shoes of different wearing time (new, 2-, 4-, 6- and 8-week) and hardness (soft, medium...
journal_title：Journal of sports sciences
pub_type： 杂志文章
doi：10.1080/02640414.2019.1633158
更新日期：2019-10-01 00:00:00
abstract：:In this crossover study, we wished to determine if normalized inter-limb differences in strength differed from inter-limb differences in voluntary activation at 30°, 70°, and 90° of knee flexion. We also assessed the relationship between inter-limb differences in torque with the inter-limb differences in activation. T...
journal_title：Journal of sports sciences
pub_type： 杂志文章
doi：10.1080/02640414.2011.645054
更新日期：2012-01-01 00:00:00
abstract：:Research indicates that instructing athlete's to focus on bodily movements (internal focus of attention [IFA]) may hinder performance, whereas instructing them to focus on the movement outcome (external focus of attention [EFA]) often enhances performance. Despite the importance of instructions in striking combat spor...
journal_title：Journal of sports sciences
pub_type： 杂志文章,随机对照试验
doi：10.1080/02640414.2016.1175651
更新日期：2017-03-01 00:00:00
abstract：:Nine male triathletes were studied during 160 min of exercise at 65% VO2 max on two occasions to examine the effect of glucose polymer ingestion on energy and fluid balance. During one trial they received 200 ml of a 10% glucose polymer solution at 20 min intervals during exercise (CHO), while in the other they receiv...
journal_title：Journal of sports sciences
pub_type： 临床试验,杂志文章
doi：10.1080/02640418908729817
更新日期：1989-04-01 00:00:00
abstract：:We tested a hypothetical model that examined both the effects of implicit theories of ability on the judgement of cheating acceptability in a physical education context and the mediating role of the achievement goals defined in the social-cognitive model of achievement motivation. Data were collected from 477 middle-s...
journal_title：Journal of sports sciences
pub_type： 杂志文章
doi：10.1080/02640414.2010.484065
更新日期：2010-06-01 00:00:00
abstract：:Previous research has highlighted the positive effect that different warm-up protocols have on golf performance (e.g. Sorbie et al., 2016; Tilley & Macfarlane, 2012) with the design of warm-ups and programmes targeting and improving golf performance through the activation and development of specific muscle groups. Thi...
journal_title：Journal of sports sciences
pub_type： 杂志文章,随机对照试验
doi：10.1080/02640414.2018.1522699
更新日期：2019-03-01 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
doi：10.1080/02640414.2018.1559979
更新日期：2019-06-01 00:00:00
abstract：:Exercise and treating hyperlipidaemia with statins are two integral components of the American Heart Association guidelines to reduce cardiovascular risk in adults. Since statins can cause myalgias and myopathies, they could affect the duration or intensity of an exercise regimen. To determine the impact of statin use...
journal_title：Journal of sports sciences
pub_type： 杂志文章
doi：10.1080/02640414.2014.942688
更新日期：2015-01-01 00:00:00
abstract：:Sports coaches operate within a complex, ever-changing environment that imposes many pressures on them. Here, we address the psychological impact of these demands via a critical review of the literature pertaining to stress in sport coaches. The narrative is divided into three main sections: (1) conceptual and definit...
journal_title：Journal of sports sciences
pub_type： 杂志文章,评审
doi：10.1080/02640410903406208
更新日期：2010-01-01 00:00:00
abstract：:Youth athletes are known to be at high risk of musculoskeletal (MSK) injuries. Children in developed countries are increasingly adopting a sedentary lifestyle. Although some risk factors related to sports activities have been reported, the effect of lifestyle (i.e. screen time behaviour) on MSK pain in youth athletes ...
journal_title：Journal of sports sciences
pub_type： 杂志文章
doi：10.1080/02640414.2017.1420453
更新日期：2018-08-01 00:00:00
abstract：:In this study, we examined (1) the relationship between self-talk and affect and (2) the nature of motivating self-talk. Ninety high-school athletes completed the Affect Grid and the Self-Talk Grid before practice and competition. Significant positive second-order partial correlations of low to moderate strength offer...
journal_title：Journal of sports sciences
pub_type： 临床试验,杂志文章
doi：10.1080/026404101750238926
更新日期：2001-07-01 00:00:00
abstract：:The aim of this study was to integrate both dispositional and situational factors to examine their interactive ability to predict pre-competitive goal states of task and ego involvement in a sample of National junior tennis players. The Task and Ego Orientation in Sport Questionnaire (Chi and Duda, 1995) and a set of ...
journal_title：Journal of sports sciences
pub_type： 杂志文章
doi：10.1080/02640419808559364
更新日期：1998-05-01 00:00:00
abstract：:The number and type of landings performed after blocking during volleyball matches has been related to the potential risk of ACL injury. The aim of the present study was to determine whether gender affects the frequency of specific blocking landing techniques with potential risk of ACL injury from the perspective of f...
journal_title：Journal of sports sciences
pub_type： 杂志文章
doi：10.1080/02640414.2017.1346817
更新日期：2018-04-01 00:00:00
abstract：:The present study examined exercise affect during volume-load matched, high-velocity, low-load and low-velocity, high-load resistance exercise conditions in older adults. Ten older adults completed three sets of eight exercises on six separate occasions (three high-velocity, low-load and three low-velocity, high-load ...
journal_title：Journal of sports sciences
pub_type： 杂志文章,随机对照试验
doi：10.1080/02640414.2017.1405710
更新日期：2018-07-01 00:00:00
abstract：:In this article, we present a critical review of the swimming literature on body roll, for the purposes of summarizing and highlighting existing knowledge, identifying the gaps and limitations, and stimulating further research. The main research findings can be summarized as follows: swimmers roll their shoulders sign...
journal_title：Journal of sports sciences
pub_type： 杂志文章,评审
doi：10.1080/02640410903508847
更新日期：2010-02-01 00:00:00
abstract：:In this study, we investigated the effect of water immersion on physical test performance and perception of fatigue/recovery during a 4-day simulated soccer tournament. Twenty high-performance junior male soccer players (age 15.9 +/- 0.6 years) played four matches in 4 days and undertook either cold-water immersion (1...
journal_title：Journal of sports sciences
pub_type： 杂志文章
doi：10.1080/02640410802603855
更新日期：2009-04-01 00:00:00
abstract：:It is shown how to derive the appropriate cubic equation relating power and the effects of friction, gradient and wind resistance on the speed of a human-powered vehicle (HPV). The effects of gradient and wind resistance are explored for parameters representing a typical racing cyclist. The principal conclusion may be...
journal_title：Journal of sports sciences
pub_type： 杂志文章
doi：10.1080/02640419408732191
更新日期：1994-10-01 00:00:00
abstract：:The aim of this study was to assess the effects of quality of opposition and match status on technical and tactical volleyball performances, as measured by block, attack, serve, and set actions related to the tasks, space, players, and efficacy of selected game actions. Twenty-five matches from the men's World Cup 200...
journal_title：Journal of sports sciences
pub_type： 杂志文章
doi：10.1080/02640414.2011.552516
更新日期：2011-04-01 00:00:00
abstract：:The purpose of this study was to investigate the effect of an imagery training programme on the performance of a soccer task by skilled and novice players. An initial assessment of performance on the soccer task was undertaken, and then 22 skilled and 22 novice players were equally and randomly assigned to either a co...
journal_title：Journal of sports sciences
pub_type： 临床试验,杂志文章,随机对照试验
doi：10.1080/02640419308729971
更新日期：1993-04-01 00:00:00
