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The cyclical changes in sex hormones across the menstrual cycle (MC) are associated with various biological changes that may alter resting metabolic rate (RMR) and body composition estimates. Hormonal contraceptive (HC) use must also be considered given their impact on endogenous sex hormone concentrations and synchronous exogenous profiles. The purpose of this study was to determine if RMR and dual-energy X-ray absorptiometry body composition estimates change across the MC and differ compared with HC users. This was accomplished during a 5-week training camp involving naturally cycling athletes (n = 11) and HC users (n = 7 subdermal progestin implant, n = 4 combined monophasic oral contraceptive pill, n = 1 injection) from the National Rugby League Indigenous Women's Academy. MC phase was retrospectively confirmed via serum estradiol and progesterone concentrations and a positive ovulation test. HC users had serum estradiol and progesterone concentrations assessed at the time point of testing. Results were analyzed using general linear mixed model. There was no effect of MC phase on absolute RMR (p =.877), relative RMR (p =.957), or dual-energy X-ray absorptiometry body composition estimates (p >.05). There was no effect of HC use on absolute RMR (p =.069), relative RMR (p =.679), or fat mass estimates (p =.766), but HC users had a greater fat-free mass and lean body mass than naturally cycling athletes (p =.028). Our findings suggest that RMR and dual-energy X-ray absorptiometry body composition estimates do not significantly differ due to changes in sex hormones in a group of athletes, and measurements can be compared between MC phases or with HC usage without variations in sex hormones causing additional noise. [ABSTRACT FROM AUTHOR]

The aim of this audit was to quantify female representation in research on heat adaptation. Using a standardized audit tool, the PubMed database was searched for heat adaptation literature from inception to February 2023. Studies were included if they investigated heat adaptation among female and male adults (≥18–50 years) who were free from noncommunicable diseases, with heat adaptation the primary or secondary outcome of interest. The number and sex of participants, athletic caliber, menstrual status, research theme, journal impact factor, Altmetric score, Field-Weighted Citation Impact, and type of heat exposure were extracted. A total of 477 studies were identified in this audit, including 7,707 participants with ∼13% of these being female. Most studies investigated male-only cohorts (∼74%, n = 5,672 males), with ∼5% (n = 360 females) including female-only cohorts. Of the 126 studies that included females, only 10% provided some evidence of appropriate methodological control to account for ovarian hormone status, with no study meeting best-practice recommendations. Of the included female participants, 40% were able to be classified to an athletic caliber, with 67% of these being allocated to Tier 2 (i.e., trained/developmental) or below. Exercise heat acclimation was the dominant method of heat exposure (437 interventions), with 21 studies investigating sex differences in exercise heat acclimation interventions. We recommend that future research on heat adaptation in female participants use methodological approaches that consider the potential impact of sexual dimorphism on study outcomes to provide evidence-based guidelines for female athletes preparing for exercise or competition in hot conditions. [ABSTRACT FROM AUTHOR]

Context.--A severe third wave of COVID-19 disease affected Ireland in the first 3 months of 2021. In this wave, 1 second-trimester miscarriage and 6 stillbirths were observed in the Irish population because of placental insufficiency as a result of SARS-CoV-2 placentitis. This observation was at odds with the country's previous experience with COVID-19 disease in pregnant mothers. Objective.--To describe the clinical and pathologic features of these pregnancy losses. Design.--Retrospective review of clinical and pathologic data of cases of second-trimester miscarriage, stillbirth, or neonatal death identified by perinatal pathologists as being due to SARS-CoV-2 placentitis during the third wave of COVID-19 in Ireland. Results.--Clinical and pathologic data were available for review in 6 pregnancies. Sequencing or genotyping of the virus identified SARS-CoV-2 alpha (B.1.1.7) in all cases. Three of the 6 cases had maternal thrombocytopenia, and fetal growth restriction was not prominent, suggesting a rapidly progressive placental disease. Conclusions.--The identification of SARS-CoV-2 alpha in all these cases suggests that the emergence of the variant was associated with an increased risk of fetal death due to SARS-CoV-2 placentitis when compared with the original virus. Maternal thrombocytopenia may have potential as a clinical marker of placentitis, but other inflammatory markers need investigation. Three of the 6 women had been assessed for reduced fetal movements in hospital some days before the fetal deaths actually occurred; this could suggest that there may be a window for intervention in some cases. (Arch Pathol Lab Med. 2022;146:529-537; doi: 10.5858/ arpa.2021-0586-SA), SARS-CoV-2 placentitis represents a readily recognizable pattern of placental injury occurring in some pregnant women who develop COVID-19. (1) Pregnant women are at increased risk of severe COVID-19-associated illness compared [...]

Endurance exercise can disturb intestinal epithelial integrity, leading to increased systemic indicators of cell injury, hyperpermeability, and pathogenic translocation. However, the interaction between exercise, diet, and gastrointestinal disturbance still warrants exploration. This study examined whether a 6-day dietary intervention influenced perturbations to intestinal epithelial disruption in response to a 25-km race walk. Twenty-eight male race walkers adhered to a high carbohydrate (CHO)/energy diet (65% CHO, energy availability = 40 kcal·kg FFM−1·day−1) for 6 days prior to a Baseline 25-km race walk. Athletes were then split into three subgroups: high CHO/energy diet (n = 10); low-CHO, high-fat diet (LCHF: n = 8; <50 g/day CHO, energy availability = 40 kcal·kg FFM−1·day−1); and low energy availability (n = 10; 65% CHO, energy availability = 15 kcal·kg FFM−1·day−1) for a further 6-day dietary intervention period prior to a second 25-km race walk (Adaptation). During both trials, venous blood was collected pre-, post-, and 1 hr postexercise and analyzed for markers of intestinal epithelial disruption. Intestinal fatty acid-binding protein concentration was significantly higher (twofold increase) in response to exercise during Adaptation compared to Baseline in the LCHF group (p =.001). Similar findings were observed for soluble CD14 (p <.001) and lipopolysaccharide-binding protein (p =.003), where postexercise concentrations were higher (53% and 36%, respectively) during Adaptation than Baseline in LCHF. No differences in high CHO/energy diet or low energy availability were apparent for any blood markers assessed (p >.05). A short-term LCHF diet increased intestinal epithelial cell injury in response to a 25-km race walk. No effect of low energy availability on gastrointestinal injury or symptoms was observed. [ABSTRACT FROM AUTHOR]

Sport science practitioners utilise findings from peer reviewed research to inform practice. Fewer studies are conducted with high performance athletes, however, than those involving recreationally active participants. Noting that research findings from recreational athletes may not be generalisable to the elite, there is a need to engage the latter cohort in research with better potential to influence health and performance. This study identified methods used to engage and recruit highly trained, elite and world class athletes as research participants. A document analysis was conducted using a purposive sample of peer‐reviewed sport science literature. All articles published in 2022 from 18 highly ranked sport science journals were screened for inclusion. Studies investigating athletes ranked as highly trained/national level or above were included. All details related to participant recruitment were extracted from included articles, with the content being coded and thematically analysed using an interpretivist approach. A total of 439 studies from the 2356 screened were included in the analysis. Five primary themes of recruitment strategies were identified, beneath an overarching strategy of purposeful, convenience sampling. Recruitment themes related to the use of a gatekeeper, the research environment providing convenient access to athletes, promoting the study electronically, utilising professional networks and recruiting at training or competition. Engaging athletes through a gatekeeper is a prominent strategy to involve elite athletes in research. It is suggested that researchers work collaboratively with team or organisation personnel to promote recruitment, creating co‐designed approaches that address issues most relevant to athletes and staff. Highlights: Engaging elite athletes through a gatekeeper appears to be a successful strategy for participant recruitment.Embedding a researcher within the sporting organisation or team, or collaborating with team personnel, are two possible approaches to using a gatekeeper and will likely promote recruitment as well as the co‐design of sport science research.Taking advantage of the university environment where student‐athletes are available is a convenient and potentially effective approach to engaging athletes for recruitment. [ABSTRACT FROM AUTHOR]

Aim: To investigate how delayed post‐exercise carbohydrate intake affects muscle glycogen, metabolic‐ and mitochondrial‐related molecular responses, and subsequent high‐intensity interval exercise (HIIE) capacity. Methods: In a double‐blind cross‐over design, nine recreationally active men performed HIIE (10 × 2‐min cycling, ~94% W˙peak) in the fed state, on two occasions. During 0–3 h post‐HIIE, participants drank either carbohydrates ("Immediate Carbohydrate" [IC], providing 2.4 g/kg) or water ("Delayed Carbohydrate" [DC]); total carbohydrate intake over 24 h post‐HIIE was matched (~7 g/kg/d). Skeletal muscle (sampled pre‐HIIE, post‐HIIE, +3 h, +8 h, +24 h) was analyzed for whole‐muscle glycogen and mRNA content, plus signaling proteins in cytoplasmic‐ and nuclear‐enriched fractions. After 24 h, participants repeated the HIIE protocol until failure, to test subsequent HIIE capacity; blood lactate, heart rate, and ratings of perceived effort (RPE) were measured throughout. Results: Muscle glycogen concentrations, and relative changes, were similar between conditions throughout (p > 0.05). Muscle glycogen was reduced from baseline (mean ± SD mmol/kg dm; IC: 409 ± 166; DC: 352 ± 76) at post‐HIIE (IC: 253 ± 96; DC: 214 ± 82), +3 h (IC: 276 ± 62; DC: 269 ± 116) and + 8 h (IC: 321 ± 56; DC: 269 ± 116), returning to near‐baseline by +24 h. Several genes (PGC‐1ɑ, p53) and proteins (p‐ACCSer79, p‐P38 MAPKThr180/Tyr182) elicited typical exercise‐induced changes irrespective of condition. Delaying carbohydrate intake reduced next‐day HIIE capacity (5 ± 3 intervals) and increased RPE (~2 ratings), despite similar physiological responses between conditions. Conclusion: Molecular responses to HIIE (performed in the fed state) were not enhanced by delayed post‐exercise carbohydrate intake. Our findings support immediate post‐exercise refueling if the goal is to maximize next‐day HIIE capacity and recovery time is ≤24 h. [ABSTRACT FROM AUTHOR]

Background The coronavirus disease 2019 (COVID-19) pandemic impacted cancer services worldwide. We examined the effect of the first three pandemic waves on the number of electronic (e)-referrals to rapid access clinics (RACs) for breast, lung and prostate cancer in Ireland. Methods This study used a retrospective, repeated cross-sectional design. The predicted weekly number of e-referrals by suspected cancer types from March 2020 to May 2021 was calculated using the Holt-Winters seasonal smoothing method, based on the observed numbers from a representative pre-pandemic period (01 January 2019 to 01 March 2020) and compared this with the observed number across the first three pandemic waves (02 March 2020 to 09 May 2021). Percentage differences were calculated between observed and predicted numbers of e-referrals for the three RACs and patterns were examined in each wave. Results Observed e-referrals were lower than predicted for all three RACs in the first wave of the pandemic (15.7% lower for breast, 39.5% lower for lung and 28.1% lower for prostate) with varying levels of recovery in the second and third waves for the three e-referral types. Conclusions The COVID-19 pandemic impacted patterns of e-referrals to RACs in the first three pandemic waves in Ireland. Early identification of changes in engagement with health services, such as a decrease in primary care presentations with a resultant decrease in e-referrals to RACs can allow for a rapid response from cancer control programmes. Continued surveillance of the impact of service disruption on cancer services allows policy makers and strategic leaders in cancer control programmes to respond rapidly to mitigate the impact on cancer outcomes. [ABSTRACT FROM AUTHOR]

Ecological momentary assessment (EMA) is a way to evaluate experiences in everyday life. It is a powerful research tool but can be complex and challenging for beginners. Application of EMA in audiological research brings with it opportunities and challenges that differ from other research disciplines. This tutorial discusses important considerations when conducting EMA studies in hearing care. While more research is needed to develop specific guidelines for the various potential applications of EMA in hearing research, we hope this article can alert hearing researchers new to EMA to pitfalls when using EMA and help strengthen their study design. The current article elaborates study design details, such as choice of participants, representativeness of the study period for participants' lives, and balancing participant burden with data requirements. Mobile devices and sensors to collect objective data on the acoustic situation are reviewed alongside different possibilities for EMA setups ranging from online questionnaires paired with a timer to proprietary apps that also have access to parameters of a hearing device. In addition to considerations for survey design, a list of questionnaire items from previous studies is provided. For each item, an example and a list of references are given. EMA typically provides data sets that are rich but also challenging in that they are noisy, and there is often unequal amount of data between participants. After recommendations on how to check the data for compliance, reactivity, and careless responses, methods for statistical analysis on the individual level and on the group level are discussed including special methods for direct comparison of hearing device programs. [ABSTRACT FROM AUTHOR]

Purpose: To examine the effects of a high-carbohydrate diet (HCHO), periodized-carbohydrate (CHO) diet (PCHO), and ketogenic low-CHO high-fat diet (LCHF) on training capacity. Methods: Elite male racewalkers completed 3 weeks of periodic training while adhering to their dietary intervention. Twenty-nine data sets were collected from 21 athletes. Each week, 6 mandatory training sessions were completed, with additional sessions performed at the athlete's discretion. Mandatory sessions included an interval session (10 × 1-km efforts on a 6-min cycle), tempo session (14 km with a 450-m elevation gain), 2 long walks (25–40 km), and 2 easy walks (8–12 km) where "sleep-low" and "train-low" dietary strategies were employed for PCHO. Racewalking speed, heart rate, rating of perceived exhaustion, and blood metabolites were collected around key sessions. Results: LCHF covered less total distance than HCHO and PCHO (P <.001); however, no differences in training load between groups were evident (P =.285). During the interval sessions, walking speed was slower in LCHF (P =.001), equating to a 2.8% and 5.6% faster speed in HCHO and PCHO, respectively. LCHF was also 3.2% slower in completing the tempo session than HCHO and PCHO (P =.001). Heart rate was higher (P =.002) and lactate concentrations were lower (P <.001) in LCHF compared to other groups, despite slower walking speeds during the interval session. No between-groups differences in rating of perceived exhaustion were evident (P =.077). Conclusion: Athletes adhering to an LCHF diet showed impaired training capacity relative to their high-CHO-supported counterparts, completing lower training volumes at slower speeds, with higher heart rates. [ABSTRACT FROM AUTHOR]

The aim of this audit was to assess the representation of female athletes, dietary control methods, and gold standard female methodology that underpins the current guidelines for chronic carbohydrate (CHO) intake strategies for athlete daily training diets. Using a standardized audit, 281 studies were identified that examined high versus moderate CHO, periodized CHO availability, and/or low CHO, high fat diets. There were 3,735 total participants across these studies with only ∼16% of participants being women. Few studies utilized a design that specifically considered females, with only 16 studies (∼6%) including a female-only cohort and six studies (∼2%) with a sex-based comparison in their statistical procedure, in comparison to the 217 studies (∼77%) including a male-only cohort. Most studies (∼72%) did not provide sufficient information to define the menstrual status of participants, and of the 18 studies that did, optimal methodology for control of ovarian hormones was only noted in one study. While ∼40% of male-only studies provided all food and beverages to participants, only ∼20% of studies with a female-specific design used this approach for dietary control. Most studies did not implement strategies to ensure compliance to dietary interventions and/or control energy intake during dietary interventions. The literature that has contributed to the current guidelines for daily CHO intake is lacking in research that is specific to, or adequately addresses, the female athlete. Redressing this imbalance is of high priority to ensure that the female athlete receives evidence-based recommendations that consider her specific needs. [ABSTRACT FROM AUTHOR]

This review discusses the potential value of tracking interstitial glucose with continuous glucose monitors (CGMs) in athletes, highlighting possible applications and important considerations in the collection and interpretation of interstitial glucose data. CGMs are sensors that provide real time, longitudinal tracking of interstitial glucose with a range of commercial monitors currently available. Recent advancements in CGM technology have led to the development of athlete-specific devices targeting glucose monitoring in sport. Although largely untested, the capacity of CGMs to capture the duration, magnitude, and frequency of interstitial glucose fluctuations every 1–15 min may present a unique opportunity to monitor fueling adequacy around competitive events and training sessions, with applications for applied research and sports nutrition practice. Indeed, manufacturers of athlete-specific devices market these products as a "fueling gauge," enabling athletes to "push their limits longer and get bigger gains." However, as glucose homeostasis is a complex phenomenon, extensive research is required to ascertain whether systemic glucose availability (estimated by CGM-derived interstitial glucose) has any meaning in relation to the intended purposes in sport. Whether CGMs will provide reliable and accurate information and enhance sports nutrition knowledge and practice is currently untested. Caveats around the use of CGMs include technical issues (dislodging of sensors during periods of surveillance, loss of data due to synchronization issues), practical issues (potential bans on their use in some sporting scenarios, expense), and challenges to the underpinning principles of data interpretation, which highlight the role of sports nutrition professionals to provide context and interpretation. [ABSTRACT FROM AUTHOR]

Current guidelines for prolonged altitude exposure suggest altitude levels ranging from 2000 to 2500 m to optimize an increase in total hemoglobin mass (Hbmass). However, natural low altitude locations (<2000 m) remain popular, highlighting the interest to investigate any possible benefit of low altitude camps for endurance athletes. Ten elite racewalkers (4 women and 6 men) underwent a 4‐week "live high‐train high" (LHTH) camp at an altitude of 1720 m (PIO2 = 121 mmHg; 20.1°C; 67% relative humidity [RH]), followed by a 3‐week tapering phase (20 m; PIO2 = 150 mmHg; 28.3°C; 53% RH) in preparation for the World Athletics Championships (WC). Venous blood samples were withdrawn weekly during the entire observation period. In addition, blood volumes were determined weekly by carbon monoxide rebreathing during altitude exposure and 2 weeks after return to sea level. High‐level performances were achieved at the WC (five placings among the Top 10 WC races and three all‐time career personal bests). A slight but significant increase in absolute (+1.7%, p = 0.03) and relative Hbmass (+2.3%, p = 0.02) was observed after 4‐week LHTH. In addition, as usually observed during LHTH protocols, weekly training distance (+28%, p = 0.02) and duration (+30%, p = 0.04) significantly increased during altitude compared to the pre‐LHTH period. Therefore, although direct causation cannot be inferred, these results suggest that the combination of increased training load at low altitudes with a subsequent tapering period in a warm environment is a suitable competition‐preparation strategy for elite endurance athletes. Highlights: Despite current guidelines for prolonged altitude exposure, natural low altitude locations (<2000 m) remain popular among elite endurance athletes, highlighting the interest to investigate any possible benefit of low altitude camps.This study reports that elite racewalkers achieved a modest but significant increase in Hbmass after a 4‐week LHTH camp at an altitude of 1720 m. Furthermore, this intervention led to performance success at the subsequent World Athletics Championships.The combination of an increased training load while exposed to low altitude is suggested as a valuable competition preparation strategy for elite endurance athletes. [ABSTRACT FROM AUTHOR]

We examined performance across one menstrual cycle (MC) and 3 weeks of hormonal contraceptives (HC) use to identify whether known fluctuations in estrogen and progesterone/progestin are associated with functional performance changes. National Rugby League Indigenous Women's Academy athletes [n = 11 naturally menstruating (NM), n = 13 using HC] completed performance tests [countermovement jump (CMJ), squat jump (SJ), isometric mid‐thigh pull, 20 m sprint, power pass and Stroop test] during three phases of a MC or three weeks of HC usage, confirmed through ovulation tests alongside serum estrogen and progesterone concentrations. MC phase or HC use did not influence jump height, peak force, sprint time, distance thrown or Stroop effect. However, there were small variations in kinetic and kinematic CMJ/SJ outputs. NM athletes produced greater mean concentric power in MC phase four than one [+0.41 W·kg−1 (+16.8%), p = 0.021] during the CMJ, alongside greater impulse at 50 ms at phase one than four [+1.7 N·s (+4.7%), p = 0.031] during the SJ, without differences between tests for HC users. Among NM athletes, estradiol negatively correlated with mean velocity and power (r = −0.44 to −0.50, p < 0.047), progesterone positively correlated with contraction time (r = 0.45, p = 0.045), and both negatively correlated with the rate of force development and impulse (r = −0.45 to −0.64, p < 0.043) during the SJ. During the CMJ, estradiol positively correlated to 200 ms impulse (r = 0.45, p = 0.049) and progesterone to mean power (r = 0.51, p = 0.021). Evidence of changes in testing performance across a MC, or during active HC use, is insufficient to justify "phase‐based testing"; however, kinetic or kinematic outputs may be altered in NM athletes. Highlights: Evidence of changes in testing performance across a menstrual cycle, or during active hormonal contraceptives use, is insufficient to justify "phase‐based testing" at a group or team‐based level among female rugby league athletes.Kinetic or kinematic outputs in jumping movements may be altered in naturally menstruating athletes; however it could not be determined if the observed alterations exceeded between‐day variability. [ABSTRACT FROM AUTHOR]