The Effect of Heat Acclimatization and Heat Acclimation on Endurance Trained Athlete Substrate Utilization

Heat acclimatization (HAz) and Heat Acclimation (HA) are important strategies to induce thermoregulatory adaptations to mitigate negative impact of heat stress. However, despite improving endurance performance, few studies explore their impact on substrate utilization. PURPOSE: To investigate the effect of HAz and HA on endurance athlete substrate utilization during submaximal exercise in the heat. METHODS: Fourteen endurance-trained male athletes (mean ± SD; age, 33 ± 9 years; body mass, 70.9 ± 10.1 kg; height, 177.7 ± 6.4 cm; VO2max, 59.3 ± 7.4 ml·kg−1·min−1; % body fat, 8.5% ± 3.9%) participated in this study. Participants performed 60 mins bouts of submaximal exercise (58.9 ± 2.2% vVO2max) in the heat (ambient temperature [Tamb], 35.5 ± 0.2°C; %relative humidity [%RH], 46.4% ± 1.3%; wet bulb globe temperature [WBGT], 29.3 ± 0.3°C; wind speed 4.0 ± 0.1 km·h−1). Prior to heat exposure (baseline), following HAz (post-HAz), and post-HA. During 60 min exercise, oxygen consumption (VO2) and respiratory exchange ratio (RER) were measured at the beginning (5-10 min), middle (30-35 min), and ending stages (55-60 min) of the protocol. Following the baseline, participants underwent self-directed summer training (HAz). Following post-HAz trials, participants underwent 5 days of HA sessions, which involved exercising to induce hyperthermia (38.50°C-39.75°C) for 60 minutes in the heat (Tamb, 39.1 ± 0.5°C; %RH, 51.8% ± 2.6%; WBGT, 33.4 ± 0.8°C) over an eight-day stretch. RESULTS: RER was significantly higher post-HAz (mean ± standard error; 0.85 ± 0.01) compared to baseline (0.81 ± 0.01, p2 difference between baseline (38.9 ± 1.2 ml·kg−1·min−1), post-HAz (37.5 ± 1.3 ml·kg−1·min−1, p= 0.062), or post-HA (38.5 ± 1.3 ml·kg−1·min−1, p=0.668). CONCLUSION: Self-directed HAz may impact athlete substrate utilization when performing submaximal exercise in a heated environment. Additionally, RER decreases as time of submaximal exercise in the heat increases. Other factors such as, athlete fitness level and exercise intensity, should also be considered when drawing conclusions regarding RER

Deconstructing Stereotypes: Stature, Match-playing Time, and Performance in Elite Women\u27s World Cup Soccer

Recruiting companies recommend elite female soccer players be ≥165 cm (5\u275″) in stature. This study investigated if stature limits match-playing time and performance in elite World Cup soccer among players, positions, and countries. We hypothesized stature would not affect match-playing time or performance. Descriptive data were collected on 552 players from 2019 FIFA Women\u27s World Cup. Odds ratios determined likelihood of starting for players ≥165 cm. ANOVAs compared playing time between stature groups, among positions, and between countries. Performance factors including assists, goals, attempts, corners, shots blocked, and defending blocks were reported. Independent t-tests compared differences between players (≥165 cm, \u3c 165 cm). Data are reported, mean difference [95% confidence interval] [MD (95%CI)] and effect sizes (ES). On average, 32.3% of players were F = 0.98, p = 0.32), matches (F = 0.27 p = 0.59), or average minutes per match (F = 0.48, p = 0.49) between stature groups, regardless of position. No differences existed in playing time between players ≥165 cm among any positions (p \u3e 0.05), or between countries (p \u3e 0.05). Taller mid-fielders exhibited greater performance in goals, assists, attempts, shots blocked, and defending blocks (MD [95%CI] ES; assists, -0.44[-0.76,-0.11]0.59, p = 0.009; goals, -0.35[-0.69,-0.01]0.44, p = 0.047); attempts, 3.14[1.38, 4.90]0.80, p = 0.001; corners, 2.04[0.12, 3.95]0.48, p = 0.037; shots blocked, 0.96[0.40, 1.51]0.75, p = 0.001; defending blocks, 0.43[0.32,0.82]0.48, p = 0.035), however, actual differences were minimal. Our findings indicate stature does not inhibit playing and performing elite women\u27s soccer, as nearly one-third of players were \u3c165 \u3ecm

Deconstructing stereotypes: Stature, match-playing time, and performance in elite Women's World Cup soccer

Recruiting companies recommend elite female soccer players be ≥165 cm (5′5″) in stature. This study investigated if stature limits match-playing time and performance in elite World Cup soccer among players, positions, and countries. We hypothesized stature would not affect match-playing time or performance. Descriptive data were collected on 552 players from 2019 FIFA Women's World Cup. Odds ratios determined likelihood of starting for players <165 cm and ≥165 cm. ANOVAs compared playing time between stature groups, among positions, and between countries. Performance factors including assists, goals, attempts, corners, shots blocked, and defending blocks were reported. Independent t-tests compared differences between players (≥165 cm, < 165 cm). Data are reported, mean difference [95% confidence interval] [MD (95%CI)] and effect sizes (ES). On average, 32.3% of players were <165 cm. Of total players, no differences existed in total minutes (F = 0.98, p = 0.32), matches (F = 0.27 p = 0.59), or average minutes per match (F = 0.48, p = 0.49) between stature groups, regardless of position. No differences existed in playing time between players <165 cm and ≥165 cm among any positions (p > 0.05), or between countries (p > 0.05). Taller mid-fielders exhibited greater performance in goals, assists, attempts, shots blocked, and defending blocks (MD [95%CI] ES; assists, −0.44[−0.76,−0.11]0.59, p = 0.009; goals, −0.35[−0.69,−0.01]0.44, p = 0.047); attempts, 3.14[1.38, 4.90]0.80, p = 0.001; corners, 2.04[0.12, 3.95]0.48, p = 0.037; shots blocked, 0.96[0.40, 1.51]0.75, p = 0.001; defending blocks, 0.43[0.32,0.82]0.48, p = 0.035), however, actual differences were minimal. Our findings indicate stature does not inhibit playing and performing elite women's soccer, as nearly one-third of players were <165 cm

Heat Safety in the Workplace:Modified Delphi Consensus to Establish Strategies and Resources to Protect U.S Workers

The purpose of this consensus document was to develop feasible, evidence‐based occupational heat safety recommendations to protect the US workers that experience heat stress. Heat safety recommendations were created to protect worker health and to avoid productivity losses associated with occupational heat stress. Recommendations were tailored to be utilized by safety managers, industrial hygienists, and the employers who bear responsibility for implementing heat safety plans. An interdisciplinary roundtable comprised of 51 experts was assembled to create a narrative review summarizing current data and gaps in knowledge within eight heat safety topics: (a) heat hygiene, (b) hydration, (c) heat acclimatization, (d) environmental monitoring, (e) physiological monitoring, (f) body cooling, (g) textiles and personal protective gear, and (h) emergency action plan implementation. The consensus‐based recommendations for each topic were created using the Delphi method and evaluated based on scientific evidence, feasibility, and clarity. The current document presents 40 occupational heat safety recommendations across all eight topics. Establishing these recommendations will help organizations and employers create effective heat safety plans for their workplaces, address factors that limit the implementation of heat safety best‐practices and protect worker health and productivity

Attitudes toward and experiences of gender issues among physician teachers: A survey study conducted at a university teaching hospital in Sweden

<p>Abstract</p> <p>Background</p> <p>Gender issues are important to address during medical education, however research about the implementation of gender in medical curricula reports that there are obstacles. The aim of this study was to explore physician teachers' attitudes to gender issues.</p> <p>Methods</p> <p>As part of a questionnaire, physician teachers at Umeå University in Sweden were given open-ended questions about explanations for and asked to write examples why they found gender important or not. The 1 469 comments from the 243 respondents (78 women, 165 men) were analyzed by way of content analysis. The proportion of comments made by men and women in each category was compared.</p> <p>Results</p> <p>We found three themes in our analysis: Understandings of gender, problems connected with gender and approaches to gender. Gender was associated with differences between women and men regarding behaviour and disease, as well as with inequality of life conditions. Problems connected with gender included: delicate situations involving investigations of intimate body parts or sexual attraction, different expectations on male and female physicians and students, and difficulty fully understanding the experience of people of the opposite sex. The three approaches to gender that appeared in the comments were: 1) avoidance, implying that the importance of gender in professional relationships was recognized but minimized by comparing gender with aspects, such as personality and neutrality; 2) simplification, implying that gender related problems were easy to address, or already solved; and 3) awareness, implying that the respondent was interested in gender issues or had some insights in research about gender. Only a few individuals described gender as an area of competence and knowledge. There were comments from men and women in all categories, but there were differences in the relative weight for some categories. For example, recognizing gender inequities was more pronounced in the comments from women and avoidance more common in comments from men.</p> <p>Conclusion</p> <p>The surveyed physician teachers gave many examples of gender-related problems in medical work and education, but comments describing gender as an area of competence and knowledge were few. Approaches to gender characterized by avoidance and simplification suggest that faculty development programs on gender need to address and reflect on attitudes as well as knowledge.</p

ABUNDANCES AND IONIZATION EQUILIBRIUM SOLUTIONS OF BROMINE, RUBIDIUM, AND XENON IN ASTROPHYSICAL NEBULAE**

To compute highly accurate Br, Rb, and Xe abundances in ionized astrophysical nebulae, we have computed large grids of numerical simulations to investigate the ionization equilibria of these elements. Br, Rb, and Xe are neutron(n)-capture elements (atomic number Z \u3e 30), which are of particular interest in planetary nebulae (PN) since they can be produced during the red giant stage of low-mass (1-8 solar mass) stars. Therefore if a PN progenitor star experienced n-capture nucleosynthesis, trans-iron elements are expected to have enhanced abundances, which can be used to infer poorly-understood physical properties of red giant stars (e.g., interior structure, convection, and mixing processes). However, only 1-2 ions of n-capture elements are typically detected in individual nebulae, and analytical “ionization correction factors” (ICFs) must be utilized to correct for unobserved ions and compute elemental abundances. To derive ICFs for Br, Rb, and Xe, we have have modified the state-of-the-art nebular modeling code Cloudy to include these elements, using recently determined atomic data for photoionization and recombination processes. We computed large grids of Cloudy models, spanning the range of physical parameters of PN, including central star temperature and luminosity, nebular density, chemical composition, and dust chemistry. We derive ICFs by identifying correlations between the fractional abundances of observed Br, Rb, and Xe ions with those of commonly detected ions of lighter species (e.g., He, O, S, Cl, and Ar). The ICFs have been used to compute Br, Rb, and Xe abundances to unprecedented accuracy in PN

The ‘state’ of tobacco: Perceptions of tobacco among Appalachian youth in Kentucky

Introduction In Appalachia, youth tobacco-use rates remain higher than the U.S. national average. Past research has indicated that several factors are related to high rates of tobacco use among Appalachian youth (e.g. low socioeconomic status, rural lifestyles). Of the Appalachian states, Kentucky has one of the highest rates of youth tobacco use. The aim of this study was to explore views of tobacco among Kentucky youth living in Appalachian counties. Methods In Fall 2014 - Spring 2015, focus group interviews were conducted with middle and high school students (N=109) in Appalachian counties in Kentucky. Each focus group session included open-ended questions and was conducted by trained facilitators. Focus group transcriptions and field notes were analyzed for themes. Results Study participants described an entrenched culture of tobacco. Three themes exemplified this culture. First, adult behavior served to enable youth tobacco use (e.g. teachers ignoring dip use in class, adults smoking with youth). Second, tobacco is easily accessible to youth (e.g. restrictions on youth sales are often ignored, family members provide). Third, symbols of tobacco are prevalent (e.g. festivals celebrating tobacco heritage, tobacco barns, and tobacco marketing logos). Conclusions Youth participants described a deeply rooted tobacco culture, which they believed was unlikely to change. Additional studies and health education efforts are needed in these rural communities. Further, stricter enforcement of tobacco sales and marketing restrictions may be helpful in protecting this vulnerable population

Presentation1_Deconstructing stereotypes: Stature, match-playing time, and performance in elite Women's World Cup soccer.zip

Recruiting companies recommend elite female soccer players be ≥165 cm (5′5″) in stature. This study investigated if stature limits match-playing time and performance in elite World Cup soccer among players, positions, and countries. We hypothesized stature would not affect match-playing time or performance. Descriptive data were collected on 552 players from 2019 FIFA Women's World Cup. Odds ratios determined likelihood of starting for players  0.05), or between countries (p > 0.05). Taller mid-fielders exhibited greater performance in goals, assists, attempts, shots blocked, and defending blocks (MD [95%CI] ES; assists, −0.44[−0.76,−0.11]0.59, p = 0.009; goals, −0.35[−0.69,−0.01]0.44, p = 0.047); attempts, 3.14[1.38, 4.90]0.80, p = 0.001; corners, 2.04[0.12, 3.95]0.48, p = 0.037; shots blocked, 0.96[0.40, 1.51]0.75, p = 0.001; defending blocks, 0.43[0.32,0.82]0.48, p = 0.035), however, actual differences were minimal. Our findings indicate stature does not inhibit playing and performing elite women's soccer, as nearly one-third of players were <165 cm.</p