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Glutamine sport

William P McCormack, Jay R Hoffman, Gabriel J Pruna, Adam R Jajtner, Jeremy R Townsend, Jeffrey R Stout, Maren S Fragala, David H Fukuda
OBJECTIVE: To examine the efficacy of l-alanyl-l-glutamine ingestion with a commercially available sports drink compared to the sports drink only on time to exhaustion and physiological measures during prolonged endurance exercise. METHODS: Twelve endurance-trained men (23.5 ± 3.7 years; 175.5 ± 5.4 cm; 70.7 ± 7.6 kg) performed 4 trials, each consisting of a 1-hour treadmill run at 75% VO2peak followed by a run to exhaustion at 90% VO2peak. One trial consisted of no hydration (NHY), another required ingestion of only a sports drink (ED), and 2 trials required ingestion of a low dose (LD; 300 mg·500 ml(-1)) and high dose (HD) of l-alanyl-l-glutamine (1 g·500 ml(-1)) added to the sports drink...
2015: Journal of the American College of Nutrition
Andrew R Mayer, Josef M Ling, Andrew B Dodd, Charles Gasparovic, Stefan D Klimaj, Timothy B Meier
Growing evidence suggests that temporally proximal acute concussions and repetitive subconcussive head injuries may lead to long-term neurological deficits. However, the underlying mechanisms of injury and their relative time-scales are not well documented in human injury models. The current study therefore investigated whether biomarkers of brain chemistry (magnetic resonance [MR] spectroscopy: N-acetylaspartate [NAA], combined glutamate and glutamine [Glx], total creatine [Cre], choline compounds [Cho], and myo-inositol [mI]) and structure (cortical thickness, white matter [WM]/subcortical volume) differed between mixed martial artists (MMA; n = 13) and matched healthy controls (HC) without a history of contact sport participation (HC; n = 14)...
November 15, 2015: Journal of Neurotrauma
Alexander P Lin, Saadallah Ramadan, Robert A Stern, Hayden C Box, Christopher J Nowinski, Brian D Ross, Carolyn E Mountford
INTRODUCTION: The goal was to identify which neurochemicals differ in professional athletes with repetitive brain trauma (RBT) when compared to healthy controls using a relatively new technology, in vivo Localized COrrelated SpectroscopY (L-COSY). METHODS: To achieve this, L-COSY was used to examine five former professional male athletes with 11 to 28 years of exposure to contact sports. Each athlete who had had multiple symptomatic concussions and repetitive sub concussive trauma during their career was assessed by an experienced neuropsychologist...
2015: Alzheimer's Research & Therapy
Gabriel J Pruna, Jay R Hoffman, William P McCormack, Adam R Jajtner, Jeremy R Townsend, Jonathan D Bohner, Michael B La Monica, Adam J Wells, Jeffrey R Stout, Maren S Fragala, David H Fukuda
The purpose of this study was to examine the effect of the L-Alanyl-L-Glutamine dipeptide (AG) on cognitive function and reaction time (RT) following endurance exercise. Twelve male endurance athletes (23.5 ± 3.7 y; 175.5 ± 5.4 cm; 70.7 ± 7.6 kg) performed four trials, each consisting of running on a treadmill at 70% of VO2max for 1h, then at 90% of VO2max until exhaustion. One trial consisted of no hydration (DHY), another required ingestion of only a sports electrolyte drink (ED) and two trials required ingestion of a low dose (LD; 300 mg·500 ml(-1)) and high dose (HD) of AG (1 g·500ml(-1)) added to the ED...
2016: European Journal of Sport Science
Kristin Wiens, Kelly Anne Erdman, Megan Stadnyk, Jill A Parnell
PURPOSE: To evaluate dietary supplement use in young Canadian athletes, their motivation for consuming supplements, and their sources of information. METHODS: A questionnaire tested for content validity and reliability was administered to 567 athletes between the ages of 11 and 25 years from the Canadian athletic community in face-to-face meetings. Demographics and sport variables were analyzed using descriptive statistics. Fisher's exact tests were used to examine dietary supplementation patterns and sources of information regarding dietary supplement use between categories of gender, age, sport type, and competition level...
December 2014: International Journal of Sport Nutrition and Exercise Metabolism
Mónica Sousa, Maria João Fernandes, Pedro Moreira, Vítor Hugo Teixeira
In this study, we determined the prevalence of nutritional supplements (NS) usage, the type of supplements used, the reasons for usage, and the source of nutritional advice among Portuguese athletes. Two hundred ninety-two athletes (68 % male, 12 - 37 years old) from 13 national sports federations completed a questionnaire that sought information on socio-demographics, sports data, and NS usage. Most athletes (66 %) consumed NS, with a median consumption of 4 supplements per athlete. The most popular supplements included multivitamins/minerals (67 %), sport drinks (62 %), and magnesium (53 %)...
2013: International Journal for Vitamin and Nutrition Research. Journal International de Vitaminologie et de Nutrition
Mark Et Willems, Chris W Sallis, Jonathan A Haskell
Muscle strength and fatigue resistance increases with resistance training. Resistance training adaptations can be enhanced with single-ingredient or dual-ingredient supplementation but less is known about resistance training adaptations by multi-ingredient supplementation. We examined the effects of a commercial multi-ingredient supplement on resistance training adaptations for training-specific and non-training-specific tasks in young males. Male participants (n = 16, age 21±2 years, body mass 74.5±5.9 kg, body height 177±5 cm) had at least 1 year experience with resistance training exercises...
June 2012: Journal of Human Kinetics
Fu-Chun Tang, Chun-Chen Chan, Po-Ling Kuo
PURPOSE: Few studies have focused on the metabolic changes induced by creatine supplementation. This study investigated the effects of creatine supplementation on plasma and urinary metabolite changes of athletes after endurance and sprint running. METHODS: Twelve male athletes (20.3 ± 1.4 y) performed two identical (65-70 % maximum heart rate reserved) 60 min running exercises (endurance trial) before and after creatine supplementation (12 g creatine monohydrate/day for 15 days), followed by a 5-day washout period...
February 2014: European Journal of Nutrition
Bryan C Mason, Mark E Lavallee
CONTEXT: Nutritional supplements advertised as ergogenic are commonly used by athletes at all levels. Health care professionals have an opportunity and responsibility to counsel athletes concerning the safety and efficacy of supplements on the market. EVIDENCE ACQUISITION: An Internet search of common fitness and bodybuilding sites was performed to identify supplement promotions. A search of MEDLINE (2000-August, 2011) was performed using the most commonly identified supplements, including glutamine, choline, methoxyisoflavone, quercetin, zinc/magnesium aspartate, and nitric oxide...
March 2012: Sports Health
P Newsholme, M Krause, E A Newsholme, S J Stear, L M Burke, L M Castell
No abstract text is available yet for this article.
March 2011: British Journal of Sports Medicine
Lindsay-Rae B Weitzel, Paul A Sandoval, W Jonathan Mayles, Paul E Wischmeyer
Many performance-enhancing supplements and/or drugs are increasing in popularity among professional and amateur athletes alike. Although the uncontrolled use of these agents can pose health risks in the general population, their clearly demonstrated benefits could prove helpful to the critically ill population in whom preservation and restoration of lean body mass and neuromuscular function are crucial. Post-intensive care unit weakness not only impairs post-intensive care unit quality of life but also correlates with intensive care unit mortality...
October 2009: Critical Care Medicine
S Hackl, R van den Hoven, M Zickl, J Spona, J Zentek
The aim of this study was to investigate the effect of short intense exercise on plasma amino acid concentrations in trotters and to test the repeatability of plasma amino acids concentration in samples obtained on two independent days under field conditions. Plasma amino acid concentrations were analysed in blood samples of 36 standardbred trotters before and after intense exercise over a distance of 2000 m. Sampling was repeated in 20 horses after 35 days. Exercise intensity was estimated from post-exercise lactate levels...
April 2009: Journal of Animal Physiology and Animal Nutrition
R J Maughan
The use of nutritional supplements in sport is widespread and few serious athletes do not, at some stage in their career, succumb to the temptation to experiment with one or more nutritional supplements. Nutritional ergogenic aids are aimed primarily at enhancing performance (either by affecting energy metabolism or by an effect on the central nervous system), at increasing lean body mass or muscle mass by stimulation of protein synthesis and at reducing body fat content. Although not strictly ergogenic (i...
December 1999: Nutrition Research Reviews
Bei Yan, Jiye A, Guangji Wang, Huali Lu, Xiaoping Huang, Yi Liu, Weibin Zha, Haiping Hao, Ying Zhang, Linsheng Liu, Shenghua Gu, Qing Huang, Yuanting Zheng, Jianguo Sun
Strength-endurance type of sport can lead to modification of human beings' physiological status. The present study aimed to investigate the alteration of metabolic phenotype or biochemical compositions in professional athletes induced by long-term training by means of a novel systematic tool, metabolomics. Resting venous blood samples of junior and senior male rowers were obtained before and after 1-wk and 2-wk training. Venous blood from healthy male volunteers as control was also sampled at rest. Endogenous metabolites in serum were profiled by GC/TOF-MS and multivariate statistical technique, i...
February 2009: Journal of Applied Physiology
M Negro, S Giardina, B Marzani, F Marzatico
Since the 1980's there has been high interest in branched-chain amino acids (BCAA) by sports nutrition scientists. The metabolism of BCAA is involved in some specific biochemical muscle processes and many studies have been carried out to understand whether sports performance can be enhanced by a BCAA supplementation. However, many of these researches have failed to confirm this hypothesis. Thus, in recent years investigators have changed their research target and focused on the effects of BCAA on the muscle protein matrix and the immune system...
September 2008: Journal of Sports Medicine and Physical Fitness
Michael Gleeson
Some athletes can have high intakes of l-glutamine because of their high energy and protein intakes and also because they consume protein supplements, protein hydrolysates, and free amino acids. Prolonged exercise and periods of heavy training are associated with a decrease in the plasma glutamine concentration and this has been suggested to be a potential cause of the exercise-induced immune impairment and increased susceptibility to infection in athletes. However, several recent glutamine feeding intervention studies indicate that although the plasma glutamine concentration can be kept constant during and after prolonged strenuous exercise, the glutamine supplementation does not prevent the postexercise changes in several aspects of immune function...
October 2008: Journal of Nutrition
Aaron J Coutts, Peter Reaburn, Terrence J Piva, Greg J Rowsell
The aim of this study was to identify indicators of non-functional overreaching (NFOR) in team sport athletes undertaking intensive training loads. Eighteen semi-professional rugby league players were randomly assigned into two pair matched groups. One group completed 6 weeks of normal training (NT) whilst the other group was deliberately overreached through intensified training (IT). Both groups then completed the same 7-day stepwise training load reduction taper. Multistage fitness test (MSFT) performance, VO2 (max), peak aerobic running velocity (V (max)), maximal heart rate, vertical jump, 10-s cycle sprint performance and body mass were measured pre- and post-training period and following the taper...
February 2007: European Journal of Applied Physiology
Sarah B Wilkinson, Paul L Kim, David Armstrong, Stuart M Phillips
We examined the effect of a post-exercise oral carbohydrate (CHO, 1 and essential amino acid (EAA, 9.25 g) solution containing glutamine (0.3 g/kg BW; GLN trial) versus an isoenergetic CHO-EAA solution without glutamine (control, CON trial) on muscle glycogen resynthesis and whole-body protein turnover following 90 min of cycling at 65% VO2 peak. Over the course of 3 h of recovery, muscle biopsies were taken to measure glycogen resynthesis and mixed muscle protein synthesis (MPS), by incorporation of [ring-2H5] phenylalanine...
October 2006: Applied Physiology, Nutrition, and Metabolism, Physiologie Appliquée, Nutrition et Métabolisme
Marcelo Macedo Rogero, Renata Rebello Mendes, Julio Tirapegui
The overtraining syndrome is characterized by an excessive training that results in several adverse effects the main of which being the decay in performance. Its incidence among elite athletes has been experiencing a significant increase lately, which prompted a rush of interest in the search for efficient measures to prevent and treat this condition. It is necessary, however, to clarify possible mechanisms involved in the development of overtraining. Several hypothesis are being proposed, such as a greater activation of both the autonomic nervous system and the hypothalamic-pituitary-adrenal axis, and suppression of the hypothalamic-pituitary-gonadal axis...
June 2005: Arquivos Brasileiros de Endocrinologia e Metabologia
Dan Nemet, Baruch Wolach, Alon Eliakim
Although dietary protein supplementation is commonly used by both athletes and people engaged in recreational sports, the data supporting its wide use are still limited. Some evidence supports the use of creatine and possibly HMB as ergogenic aids in specific situations [8], however this is also based on limited data. The use of supplements for the healthy, non-competitive adult engaged in recreational sports is usually not warranted.
May 2005: Israel Medical Association Journal: IMAJ
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