State of the Science—Ultraendurance Sports

2016 ◽  
Vol 11 (6) ◽  
pp. 831-832 ◽  
Author(s):  
Martin D. Hoffman

Participation in ultraendurance sports has been increasing in recent years. This participation growth has been associated with an increase in research focused on such events. While the total amount of research related to these sports remains relatively small compared with other sports, the research growth is encouraging. New sources for research funding for ultraendurance sports should advance the science. In addition to continued opportunities with observational studies, promising areas of investigation remain for experimental studies and research that uses ultraendurance-sport environments as models for studies relevant to wider populations. Insight into the breadth of research opportunities in ultraendurance sports can be gained by reviewing the abstracts published online in the International Journal of Sports Physiology and Performance from the annual Medicine & Science in Ultra-Endurance Sports Conference that took place this year in Chamonix, France.

Nutrients ◽  
2018 ◽  
Vol 10 (12) ◽  
pp. 1995 ◽  
Author(s):  
Pantelis Nikolaidis ◽  
Eleftherios Veniamakis ◽  
Thomas Rosemann ◽  
Beat Knechtle

Athletes competing in ultra-endurance sports should manage nutritional issues, especially with regards to energy and fluid balance. An ultra-endurance race, considered a duration of at least 6 h, might induce the energy balance (i.e., energy deficit) in levels that could reach up to ~7000 kcal per day. Such a negative energy balance is a major health and performance concern as it leads to a decrease of both fat and skeletal muscle mass in events such as 24-h swimming, 6-day cycling or 17-day running. Sport anemia caused by heavy exercise and gastrointestinal discomfort, under hot or cold environmental conditions also needs to be considered as a major factor for health and performance in ultra-endurance sports. In addition, fluid losses from sweat can reach up to 2 L/h due to increased metabolic work during prolonged exercise and exercise under hot environments that might result in hypohydration. Athletes are at an increased risk for exercise-associated hyponatremia (EAH) and limb swelling when intake of fluids is greater than the volume lost. Optimal pre-race nutritional strategies should aim to increase fat utilization during exercise, and the consumption of fat-rich foods may be considered during the race, as well as carbohydrates, electrolytes, and fluid. Moreover, to reduce the risk of EAH, fluid intake should include sodium in the amounts of 10–25 mmol to reduce the risk of EAH and should be limited to 300–600 mL per hour of the race.


2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Paola Riente ◽  
Mauro Fianchini ◽  
Patricia Llanes ◽  
Miquel A. Pericàs ◽  
Timothy Noël

AbstractThe importance of discovering the true catalytically active species involved in photocatalytic systems allows for a better and more general understanding of photocatalytic processes, which eventually may help to improve their efficiency. Bi2O3 has been used as a heterogeneous photocatalyst and is able to catalyze several synthetically important visible-light-driven organic transformations. However, insight into the operative catalyst involved in the photocatalytic process is hitherto missing. Herein, we show through a combination of theoretical and experimental studies that the perceived heterogeneous photocatalysis with Bi2O3 in the presence of alkyl bromides involves a homogeneous BinBrm species, which is the true photocatalyst operative in the reaction. Hence, Bi2O3 can be regarded as a precatalyst which is slowly converted in an active homogeneous photocatalyst. This work can also be of importance to mechanistic studies involving other semiconductor-based photocatalytic processes.


Fuel ◽  
2017 ◽  
Vol 190 ◽  
pp. 47-57 ◽  
Author(s):  
Xuehua Zou ◽  
Tianhu Chen ◽  
Haibo Liu ◽  
Ping Zhang ◽  
Zhiyuan Ma ◽  
...  

1992 ◽  
Vol 295 ◽  
Author(s):  
P. Molinàs-Mata ◽  
J. Zegenhagen ◽  
M. Böhringer ◽  
N. Takeuchi ◽  
A. Selloni

AbstractWe report on new experimental studies of the Ge(111)-c(2×8) reconstruction performed with low-energy electron diffraction. (LEED) and scanning tunneling microscopy (STM). Weak quarter-order reflections are present in the c(2 × 8) LEED pattern in agreement with previous observations and results of ab initio calculations. In order to gain insight into the predicted splitting of dangling bond states, we compare constant current topographs (CCT's) performed at high-tunneling currents (40.nA) with first-principles calculations of the local density of states (LDOS) 1Å above the surface adatoms and obtain good qualitative agreement. We finally discuss to what extent the STM CCT's at high tunneling currents (small sample-tip distances (STD)) are sensitive to surface states outside the Г point.


Author(s):  
Marcia P. Jimenez ◽  
Nicole V. DeVille ◽  
Elise G. Elliott ◽  
Jessica E. Schiff ◽  
Grete E. Wilt ◽  
...  

There is extensive empirical literature on the association between exposure to nature and health. In this narrative review, we discuss the strength of evidence from recent (i.e., the last decade) experimental and observational studies on nature exposure and health, highlighting research on children and youth where possible. We found evidence for associations between nature exposure and improved cognitive function, brain activity, blood pressure, mental health, physical activity, and sleep. Results from experimental studies provide evidence of protective effects of exposure to natural environments on mental health outcomes and cognitive function. Cross-sectional observational studies provide evidence of positive associations between nature exposure and increased levels of physical activity and decreased risk of cardiovascular disease, and longitudinal observational studies are beginning to assess long-term effects of nature exposure on depression, anxiety, cognitive function, and chronic disease. Limitations of current knowledge include inconsistent measures of exposure to nature, the impacts of the type and quality of green space, and health effects of duration and frequency of exposure. Future directions include incorporation of more rigorous study designs, investigation of the underlying mechanisms of the association between green space and health, advancement of exposure assessment, and evaluation of sensitive periods in the early life-course.


2021 ◽  
Vol 38 (1) ◽  
pp. 101-139
Author(s):  
Abigail C. Cohn ◽  
Margaret E. L. Renwick

Abstract We pursue the idea, implicit in much current phonological research, that understanding the multiple factors that shape speech production and perception is within the purview of phonology. In particular, increased access to naturalistic data has highlighted the multidimensional reality of variation in spoken language. At the same time, longstanding methods of doing phonology – including impressionistic analysis, and laboratory and experimental studies – remain crucial to understanding native speaker competence and grammar. We advocate for an expanded methodological toolbox in phonological analysis, using an iterative approach that crucially includes naturalistic corpus data. Integrating across multiple data sources offers fuller insight into the nature of the phonological system and native speaker-hearer ability. Several case studies highlight findings gained through linked, iterative studies, showing the importance of naturalistic data for a richer understanding of phonological phenomena, and leading us to reflect on desiderata for corpora to reveal speaker-specific patterns in fine phonetic detail and variability, which we argue are part of a speaker-hearer’s phonological competence. Phonological analysis that embraces the full spectrum of variation in spoken language data (from categorical to gradient, and systematic to sporadic) contributes to a deeper understanding of phonology in this richer sense.


2021 ◽  
Author(s):  
Anne Skorkjær Binderkrantz ◽  
Mette Bisgaard ◽  
Berit Lassesen

The role of gender in the interaction between citizens and public sector employees attracts increasing attention. Notably, gender effects have been described in performance evaluations across different contexts. With respect to student evaluations of teaching, a series of observational studies as well as experimental studies have found that women are evaluated lower than men. In this paper, we conduct two experiments in Denmark to test whether a similar gender bias is present in a national context that is generally considered among the most gender equal. Study 1 investigates differences in the evaluation of two similar presentations by teachers reported to be either male or female. Study 2 focuses on the evaluation of teaching material prepared by men and women respectively. The two studies arrive at similar conclusions: There is no gender bias in favor of men in the evaluations made by students. The paper discusses the implications of these findings.


2021 ◽  
Vol 23 (2) ◽  
pp. 23-29
Author(s):  
Ellie Dworak ◽  
née Laura Suzanne Hudson

Pivot-RP is a source of research funding opportunities, facilitating research collaborations, and offering insight into the funding landscape as well as internal benchmarks. Pivot-RP addresses the needs of researchers and research development professionals alike.


2022 ◽  
Vol 10 (1) ◽  
Author(s):  
Fatima Safi ◽  
Anna M. Aniserowicz ◽  
Heather Colquhoun ◽  
Jill Stier ◽  
Behdin Nowrouzi-Kia

Abstract Background Eating disorders (ED) can reduce quality of life by limiting participation and performance in social and occupational roles, including paid or unpaid work. The association between ED pathologies and work participation and performance must be well understood to strengthen vocational rehabilitation programmes and prevent occupational disruptions in the ED population. The aims of this study are: (1) to examine the degree of association between ED pathologies and work participation and performance in 15-year-olds and older; (2) to highlight the specific ED symptoms that are most correlated with changes in work performance and participation; (3) to compile the most common metrics and assessments used to measure work participation and performance with ED. Methods Medline, Embase, CINAHL, Web of Science, PsycINFO, and Cochrane Library will be searched for observational and experimental studies that meet the following criteria: (1) a clinical sample of typical or atypical ED; (2) paid or unpaid employment or training; (3) an association between ED pathologies and work participation or performance. Unpublished data will also be examined. Title and abstract, and full-text screening will be conducted in duplicate. Risk of bias and quality of evidence assessments will be completed. A random-effect meta-analysis will be performed. Discussion This synthesis can clarify knowledge and gaps around the impact of ED on work functioning, thereby allowing better evaluation, improvements and development of current workplace assessments, interventions, and policies. Trial registration The registration number for this systematic review on PROSPERO is CRD42021255055.


2019 ◽  
Author(s):  
Sarah E Rose ◽  
Alexandra Lamont ◽  
Nicholas Reyland

Correlational studies have suggested some harmful effects of television (TV) viewing in early childhood, especially for the viewing of fast-paced entertainment programs. However, this has not been consistently supported by experimental studies, many of which have lacked ecological validity. The current study explores the effects of pace of program on the attention, problem solving and comprehension of 41 3- and 4-year-olds using an ecologically valid experimental design. Children were visited twice at home; on each visit they were shown an episode of a popular animated entertainment program which differed in pace: one faster paced, one slower paced. Children’s behavior was coded for attention and arousal during viewing, attention, effort and performance after viewing during a problem-solving task, and comprehension of the program. The faster paced program was attended to more, but this had no impact on comprehension. Although 3-year-olds showed more attention and effort on the problem-solving task after watching the slower program, both 3- and 4-year-olds completed more problems successfully after watching the faster program. The results provide evidence to counter the ‘harm’ perceived in young children watching fast-paced entertainment programs as where differences were found it was the fast-paced program which appeared to have a cognitive facilitation effect.


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