Abstract：
:The mixture of dihydroxyacetone and pyruvate (DHAP) is an ergogenic aid that enhances muscle glucose extraction during prolonged aerobic exercise. In order to evaluate the effect of DHAP on muscle amino acid extraction during exercise, we measured arterial concentration and muscle exchange of amino acids in 18 untrained healthy male subjects (aged 20-30 years) performing dynamic arm (60% VO2 max, n = 9) or leg (70% VO2 max, n = 9) exercise to exhaustion with and without dietary supplementation of DHAP. The subjects consumed diets (146 kJ kg body weight-1 day-1) containing either 100 g polyglucose, Polycose (placebo, P) or DHAP (3:1, treatment) substituted for a portion of carbohydrate. The two diets were administered in a double-blind, random, crossover order for a 7-day period. At least 7 days separated the dietary protocols. Blood samples were drawn through radial artery and axillary or femoral vein catheters at rest, during exercise and at exhaustion. Arterial alanine concentration increased by 30% during arm exercise and by 50-60% during leg exercise. No other arterial amino acid concentration changed during exercise. At exhaustion, arterial alanine concentration decreased to pre-exercise levels with arm exercise but remained elevated after leg exercise. Despite changes in arterial concentrations of alanine with exercise, muscle exchange of alanine was not altered with exercise. Exercise did not alter muscle exchange of any amino acid. Arterial amino acid concentrations and muscle exchange of amino acids with exercise were similar with or without DHAP feeding.(ABSTRACT TRUNCATED AT 250 WORDS)
journal_name
J Sports Scijournal_title
Journal of sports sciencesauthors
Stanko RT,Diven WF,Robertson RJ,Spina RJ,Galbreath RW,Reilly JJ Jr,Goss FLdoi
10.1080/02640419308729958subject
Has Abstractpub_date
1993-02-01 00:00:00pages
17-23issue
1eissn
0264-0414issn
1466-447Xjournal_volume
11pub_type
临床试验,杂志文章,随机对照试验abstract：:Mental preparation has long been thought of as an important aspect of physical performance, especially in tasks requiring muscular strength. Recent studies in sport psychology have addressed this issue, mainly through the investigation of 'psych-up' strategies and effects. The overall trend in such experiments support...
journal_title：Journal of sports sciences
pub_type： 杂志文章
doi：10.1080/02640418508729733
更新日期：1985-04-01 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：:One of the first principles of cricket batsmanship that is coached from a young age is to play with a straight bat. Limited studies to date have examined whether top international batsmen use this traditionally described technique. Accordingly, we performed a descriptive, observational study of the backlift technique ...
journal_title：Journal of sports sciences
pub_type： 杂志文章
doi：10.1080/02640414.2016.1142110
更新日期：2016-10-01 00:00:00
abstract：:The present study aimed to provide reference values for lower-limb muscle power assessed during the incremental jump squat (JS) test in elite athletes (i.e., professional athletes competing at international level). We pooled data from all JS tests performed by elite athletes of different sports in two high-performance...
journal_title：Journal of sports sciences
pub_type： 杂志文章,多中心研究
doi：10.1080/02640414.2020.1783150
更新日期：2020-10-01 00:00:00
abstract：:Cross-country skiing is a complex endurance sport requiring technical skills, in addition to considerable physiological and tactical abilities. This review aims to identify biomechanical factors that influence the performance of cross-country skiers. Four electronic databases were searched systematically for original ...
journal_title：Journal of sports sciences
pub_type： 杂志文章
doi：10.1080/02640414.2020.1775375
更新日期：2020-09-01 00:00:00
abstract：:Agility is an essential part of many athletic activities. Currently, agility drill duration is the sole criterion used for evaluation of agility performance. The relationship between drill duration and factors such as acceleration, deceleration and change of direction, however, has not been fully explored. This paper ...
journal_title：Journal of sports sciences
pub_type： 杂志文章
doi：10.1080/02640414.2014.990481
更新日期：2015-01-01 00:00:00
abstract：:The purpose of this study was to determine the foot strike patterns (FSP), rearfoot position at initial contact (RPic, i.e., No INV/EVE) and foot rotation in children in relation to age. A total of 932 children aged 3 to 16 years participated in this study. A sagittal and frontal-plane video was recorded using a high-...
journal_title：Journal of sports sciences
pub_type： 杂志文章
doi：10.1080/02640414.2018.1507237
更新日期：2019-03-01 00:00:00
abstract：:This study aimed to investigate why futsal players decide to dribble. For this purpose, we analysed 396 trials comprising the dribbles (n = 132), passes (n = 131) or shots (n = 133), performed by 70 male futsal players. Passing and shooting angles, and interpersonal distance, including their rates of change (velocity ...
journal_title：Journal of sports sciences
pub_type： 杂志文章
doi：10.1080/02640414.2016.1232488
更新日期：2016-12-01 00:00:00
abstract：:While previous studies highlighted the importance of the different motivations for doing sports as proposed by self-determination theory, less emphasis has been put on the simultaneous presence of multiple motivations within the same individual. Therefore, the present study aimed to investigate the complex interaction...
journal_title：Journal of sports sciences
pub_type： 杂志文章
doi：10.1080/02640414.2020.1736765
更新日期：2020-04-01 00:00:00
abstract：:Rowers competing at the 2000 Olympic Games were measured for 38 anthropometric dimensions. The aim was to identify common physical characteristics that could provide a competitive advantage. The participants included 140 male open-class rowers, 69 female open-class rowers, 50 male lightweight rowers, and 14 female lig...
journal_title：Journal of sports sciences
pub_type： 杂志文章
doi：10.1080/02640410600812179
更新日期：2007-01-01 00:00:00
abstract：:Anterior cruciate ligament (ACL) rupture, during ski-landing, is caused by excessive knee joint forces and kinematics, like anterior tibial translation, internal tibial rotation, and valgus rotation. It is not well understood how these forces/kinematics are directly related to ski-landing impact. In the present study,...
journal_title：Journal of sports sciences
pub_type： 临床试验,杂志文章
doi：10.1080/02640414.2011.578146
更新日期：2011-08-01 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
更新日期：2009-05-01 00:00:00
abstract：:Computers have played an important supporting role in the development of experimental and theoretical sports biomechanics. The role of the computer now extends from data capture and data processing through to mathematical and statistical modelling and simulation and optimization. This paper seeks to demonstrate that e...
journal_title：Journal of sports sciences
pub_type： 杂志文章,评审
doi：10.1080/02640419508732232
更新日期：1995-06-01 00:00:00
abstract：:The purpose of this study was to analyse the effect of bike type - the 26-inch-wheel bike (26" bike) and the 29-inch-wheel bike (29" bike) - on performance in elite mountain bikers. Ten Swiss National Team athletes (seven males, three females) completed six trials with individual start on a simulated cross-country cou...
journal_title：Journal of sports sciences
pub_type： 杂志文章
doi：10.1080/02640414.2015.1119294
更新日期：2016-08-01 00:00:00
abstract：:In order to investigate further the use of standardization procedures to determine training effects on cardiac dimension and function, two groups of subjects were analysed noninvasively. A control group of sedentary men (n = 7) and an experimental group of weight lifters (n = 12) volunteered for a standard M-mode echo...
journal_title：Journal of sports sciences
pub_type： 杂志文章
doi：10.1080/02640418708729772
更新日期：1987-07-01 00:00:00
abstract：:Low back pain (LBP) is a common problem in football (soccer) players. The effect of LBP on the trunk and hip muscles in this group is unknown. The relationship between LBP and trunk muscle size and function in football players across the preseason was examined. A secondary aim was to assess hip muscle strength. Twenty...
journal_title：Journal of sports sciences
pub_type： 杂志文章
doi：10.1080/02640414.2016.1221526
更新日期：2016-12-01 00:00:00
abstract：:An important goal of the athlete's everyday diet is to provide the muscle with substrates to fuel the training programme that will achieve optimal adaptation for performance enhancements. In reviewing the scientific literature on post-exercise glycogen storage since 1991, the following guidelines for the training diet...
journal_title：Journal of sports sciences
pub_type： 杂志文章,评审
doi：10.1080/0264041031000140527
更新日期：2004-01-01 00:00:00
abstract：:Low-intensity exercise with blood flow restriction (BFR) is an increasingly common method of improving muscular strength and hypertrophy, and improving aerobic fitness, in clinical and athletic populations. The aim of this systematic review was to describe common approaches to determining occlusion pressures for BFR e...
journal_title：Journal of sports sciences
pub_type： 杂志文章
doi：10.1080/02640414.2020.1840734
更新日期：2020-11-01 00:00:00
abstract：:Electromyographic activity and the electrocardiogram were recorded during windsurfing on the water in six subjects (three females and three males). 'Beating' and 'reaching' (both with continuous pumping), 'running' and 'uphauling' were performed in light to moderate winds. The physiological signals were transmitted to...
journal_title：Journal of sports sciences
pub_type： 杂志文章
doi：10.1080/02640419608727694
更新日期：1996-04-01 00:00:00
abstract：:The aim of this study was to compare thoracic spine alignment with two- and three-dimensional calculations of shoulder alignment (defined as a line joining the acromion processes of the right and left scapula) when all measures were projected onto the transverse plane. A six-camera Vicon system was used to reconstruct...
journal_title：Journal of sports sciences
pub_type： 杂志文章
doi：10.1080/02640410252925170
更新日期：2002-06-01 00:00:00
abstract：:In any situation where heat production as a result of physical exercise exceeds heat elimination from the body by radiation and convection, the body will depend on sweat secretion and evaporation for its thermoregulation. Sweat secretion will reach maximal levels at high energy expenditures in the heat but will be lim...
journal_title：Journal of sports sciences
pub_type： 杂志文章
doi：10.1080/02640419108729871
更新日期：1991-07-01 00:00:00
abstract：:This study aimed to verify the effect of a multicomponent intervention on cardiometabolic risk factors (CMRF), and to determine the prevalence of responders on CMRF among children and adolescents with overweight/obesity. This is a quasi-experimental study, developed with 35 children and adolescents with overweight/obe...
journal_title：Journal of sports sciences
pub_type： 杂志文章
doi：10.1080/02640414.2020.1725384
更新日期：2020-03-01 00:00:00
abstract：:Training and nutrition are highly interrelated in that optimal adaptation to the demands of repeated training sessions typically requires a diet that can sustain muscle energy reserves. As nutrient stores (i.e. muscle and liver glycogen) play a predominant role in the performance of prolonged, intense, intermittent ex...
journal_title：Journal of sports sciences
pub_type： 杂志文章,评审
doi：10.1080/02640410500482727
更新日期：2006-07-01 00:00:00
abstract：:Collective efficacy research has begun to progress from simply trying to verify the relationship between collective efficacy and performance to examining the mechanisms through which collective efficacy impacts on performance. To test hypotheses concerning the impact of collective efficacy on group goal selection and ...
journal_title：Journal of sports sciences
pub_type： 临床试验,杂志文章
doi：10.1080/02640410050074386
更新日期：2000-06-01 00:00:00
abstract：:The aim of present study was to examine the relationships between serum and salivary values of free testosterone, dehydroepiandrosterone, and cortisol before and after a session of resistance exercise. Twenty-eight healthy men (mean age 40 years, s = 4) participated in the present study. Serum and salivary samples wer...
journal_title：Journal of sports sciences
pub_type： 杂志文章
doi：10.1080/02640410801919526
更新日期：2008-08-01 00:00:00
abstract：:We propose a new method, based on inertial sensors, to automatically measure at high frequency the durations of the main phases of ski jumping (i.e. take-off release, take-off, and early flight). The kinematics of the ski jumping movement were recorded by four inertial sensors, attached to the thigh and shank of junio...
journal_title：Journal of sports sciences
pub_type： 杂志文章,随机对照试验
doi：10.1080/02640414.2011.624538
更新日期：2012-01-01 00:00:00
abstract：:The purpose of this study was to examine the effects of calendar and skeletal age, anthropometric dimensions, training history and their interactions on vertical jumping height and horizontal overhead throwing velocity in a cross-section of 318 young male athletes (age range 9-16 years) participating in cross-country ...
journal_title：Journal of sports sciences
pub_type： 杂志文章
doi：10.1080/02640419208729939
更新日期：1992-10-01 00:00:00
abstract：:Maximal oxygen uptake VO(2max)) is considered the optimal method to assess aerobic fitness. The measurement of VO(2max), however, requires special equipment and training. Maximal exercise testing with determination of maximal power output offers a more simple approach. This study explores the relationship between [Vdo...
journal_title：Journal of sports sciences
pub_type： 杂志文章
doi：10.1080/02640410802199789
更新日期：2008-11-01 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：: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
