27 research outputs found
International Society of Sports Nutrition Position Stand: Nutritional recommendations for single-stage ultra-marathon; training and racing
Background. In this Position Statement, the International Society of Sports Nutrition (ISSN) provides an objective and critical review of the literature pertinent to nutritional considerations for training and racing in single-stage ultra-marathon. Recommendations for Training. i) Ultra-marathon runners should aim to meet the caloric demands of training by following an individualized and periodized strategy, comprising a varied, food-first approach; ii) Athletes should plan and implement their nutrition strategy with sufficient time to permit adaptations that enhance fat oxidative capacity; iii) The evidence overwhelmingly supports the inclusion of a moderate-to-high carbohydrate diet (i.e., ~60% of energy intake, 5 – 8 g⸱kg−1·d−1) to mitigate the negative effects of chronic, training-induced glycogen depletion; iv) Limiting carbohydrate intake before selected low-intensity sessions, and/or moderating daily carbohydrate intake, may enhance mitochondrial function and fat oxidative capacity. Nevertheless, this approach may compromise performance during high-intensity efforts; v) Protein intakes of ~1.6 g·kg−1·d−1 are necessary to maintain lean mass and support recovery from training, but amounts up to 2.5 g⸱kg−1·d−1 may be warranted during demanding training when calorie requirements are greater; Recommendations for Racing. vi) To attenuate caloric deficits, runners should aim to consume 150 - 400 kcal⸱h−1 (carbohydrate, 30 – 50 g⸱h−1; protein, 5 – 10 g⸱h−1) from a variety of calorie-dense foods. Consideration must be given to food palatability, individual tolerance, and the increased preference for savory foods in longer races; vii) Fluid volumes of 450 – 750 mL⸱h−1 (~150 – 250 mL every 20 min) are recommended during racing. To minimize the likelihood of hyponatraemia, electrolytes (mainly sodium) may be needed in concentrations greater than that provided by most commercial products (i.e., >575 mg·L−1 sodium). Fluid and electrolyte requirements will be elevated when running in hot and/or humid conditions; viii) Evidence supports progressive gut-training and/or low-FODMAP diets (fermentable oligosaccharide, disaccharide, monosaccharide and polyol) to alleviate symptoms of gastrointestinal distress during racing; ix) The evidence in support of ketogenic diets and/or ketone esters to improve ultra-marathon performance is lacking, with further research warranted; x) Evidence supports the strategic use of caffeine to sustain performance in the latter stages of racing, particularly when sleep deprivation may compromise athlete safety
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Corrigendum to Joint Healthcare Infection Society (HIS) and Infection Prevention Society (IPS) guidelines for the prevention and control of meticillin-resistant Staphylococcus aureus (MRSA) in healthcare facilities. J Hosp Infect 118 (2021) S1 – S39 (Journal of Hospital Infection (2021) 118(S) (S1–S39), (S0195670121003601), (10.1016/j.jhin.2021.09.022))
The authors regret that it has come to the attention that not all relevant parties were appropriately acknowledged in the original version of the MRSA guidelines published in the Journal of Hospital Infection in October 2021. The following changes should be made to address these omissions:Who developed these guidelines?This section should read as follows:The Working Party included infectious diseases/microbiology clinicians, IPC experts, systematic reviewers, and two lay member representatives. Updating the national guidelines relating to MRSA was a joint initiative of BSAC, BIA, HIS and IPS. HIS and IPS alone were involved in the production of this guideline. BSAC and BIA were responsible for updating recommendations for the treatment of MRSA, which are available in a separate guideline (link to) https://academic.oup.com/jacamr/article/3/1/dlaa114/6127118?guestAccessKey=20cf089c-ce33-4e54-bb62-b2131c25a137&login=falseSource of fundingThis section should read as follows:All Societies (BIA, BSAC, HIS, IPS) contributed equally to the initial cost of designing PICO questions and search strategies. Other costs specific for the IPC guidelines, e.g., the researchers' time and other resources required to conduct evidence syntheses, as well as the cost of publication were funded by HIS.The authors would like to apologise for any inconvenience caused.</p
METABOLIC PATTERN OF THE HEART OF HEMOGLOBIN-FREE AND MYOGLOBIN-FREE ANTARCTIC FISH CHANNICHTHYS-RHINOCERATUS
Myoglobin content and the activities of enzymes of energy metabolism in red and white fish hearts
Glutamine metabolism and its effects on immune response: molecular mechanism and gene expression
Insights into the critical role of NADPH oxidase(s) in the normal and dysregulated pancreatic beta cell
It is now widely accepted that reactive oxygen species (ROS) contribute to cell and tissue dysfunction and damage in diabetes. The source of ROS in the insulin secreting pancreatic beta cells has traditionally been considered to be the mitochondrial electron transport chain. While this source is undoubtedly important, we fully describe in this article recent information and evidence of NADPH oxidase-dependent generation of ROS in pancreatic beta cells and identify the various isoforms that contribute to O 2•- and H2O2 production in various conditions. While glucose-stimulated ROS generation may be important for acute regulation of insulin secretion, at higher levels ROS may disrupt mitochondrial energy metabolism. However, ROS may alter other cellular processes such as signal transduction, ion fluxes and/or cell proliferation/death. The various beta cell isoforms of NADPH oxidase (described in this review) may, via differences in the kinetics and species of ROS generated, positively and negatively regulate insulin secretion and cell survival. © 2009 Springer-Verlag