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The cellular causes of the age-related loss in power output and increased fatigability are unresolved. We previously observed that the depressive effects of hydrogen (H + ) (pH 6.2) and inorganic phosphate (P i ) (30 mm) did not differ in muscle fibres from young and older men. However, the effects may have been saturated in the severe fatigue-mimicking condition, potentially masking age differences in the sensitivity of the cross-bridge to these metabolites. Thus, we compared the contractile mechanics of muscle fibres from the vastus lateralis of 13 young (20-32 years, seven women) and 12 older adults (70-90 years, six women) in conditions mimicking quiescent muscle and a range of elevated H + (pH 6.8-6.6-6.2) and P i (12-20-30 mm). The older adult knee extensor muscles showed hallmark signs of ageing, including 19% lower thigh lean mass, 60% lower power and a greater fatigability compared to young adult muscles. Progressively increasing concentrations of H + and P i in the chemically-permeabilized fibre experiments caused a linear decrease in fibre force, velocity and power; however, the effects did not differ with age or sex. Fast fibre cross-sectional area was 41% smaller in older compared to young adults, which corresponded with lower absolute power. Size-specific power was greater in fibres from older compared to young adults, indicating the age-related decline in absolute power was explained by differences in fibre size. These data suggest the age-related loss in power is determined primarily by fast fibre atrophy in men and women, but the age-related increase in fatigability cannot be explained by an increased sensitivity of the cross-bridge to H + and P i . KEY POINTS: The causes of the age-related loss in muscle power output and the increase in fatigability during dynamic exercise remain elusive. We show that progressively increasing concentrations of hydrogen (H + ) and inorganic phosphate (P i ) causes a linear decrease in muscle fibre force, velocity and power, but the depressive effects of these metabolites on cross-bridge function did not differ in fibres from older compared to young adults across a range of fatigue-mimicking conditions. We also found peak absolute power did not differ in slow fibres from young and older adults but it was ∼33% lower in older adult fast fibres, which was explained entirely by age differences in fibre size. These data suggest that fast fibre atrophy is a major factor contributing to the loss in power of older men and women, but that the age-related increase in fatigability cannot be explained by an increased sensitivity of the cross-bridge to H + and P i ., (© 2024 The Author(s). The Journal of Physiology published by John Wiley & Sons Ltd on behalf of The Physiological Society.)

Objective: To understand the biopsychosocial dimensions of university health sciences students' experiences during the COVID-19 pandemic. Participants: Health sciences students ( n  = 297) from two universities in July and August 2020. Methods: Participants completed a Web-based survey asking about depression, anxiety, physical activity, coronavirus threat, and career commitment. Results: Moderate or severe depression and anxiety were reported by 28.6% and 31.3% of respondents, respectively. Depression and anxiety were positively correlated with perceived coronavirus threat and negatively correlated with career commitment and strenuous physical activity. A change in career commitment interests during the COVID-19 pandemic was reported by 11% of respondents. Conclusions: Identified factors that could be targeted by universities to support their students and secure career commitment include online learning challenges, ability to secure clinical placements, mental health (anxiety and depression), financial challenges, family pressure, and promotion of physical activity.

Background: To determine the impact of the COVID-19 pandemic on prenatal and postpartum depressive symptoms in rural versus urban populations., Methods: A retrospective cohort study was conducted among 24,227 cisgender women who gave birth from 2010 to 2021 at an academic medical center located in a rural midwestern state. Exclusion criteria were <18 years old, incarcerated, or without a documented zip code. The Patient Health Questionnaire-9 (PHQ-9) was administered during pregnancy and the Edinburgh Postnatal Depression Scale (EPDS) during postpartum. A sub-cohort also completed a COVID-related questionnaire. Rurality was defined as living in a county with <50,000 people. The COVID-19 era was defined as 1/1/2020 to 9/25/2021. Chi-square and Fisher exact tests were used as appropriate. Significance was set at α < 0.05., Results: Rural participants were more likely (p ≤ 0.001) to exhibit clinical depression symptoms before the pandemic in both the prenatal (8.63 % of rural participants vs. 6.49 % of urban participants) and postpartum periods (11.19 % rural vs. 9.28 % urban). During the pandemic, urban participants had increased postpartum depression. Rural participants endorsed more financial and labor concerns, whereas urban participants expressed support system concerns., Limitations: Study data were gathered from participants who gave birth at a single, midwestern hospital. Results may not be widely generalizable given the homogeneity of participants., Conclusions: Rural women experienced higher rates of prenatal and postpartum depressive symptoms compared to their urban counterparts. The COVID-19 pandemic was a significant stressor, revealing specific mental health vulnerabilities among birthing people., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Donna Santillan reports financial support was provided by National Institutes of Health. Stephen K. Hunter reports financial support was provided by Health Resources and Services Administration. Stephen K. Hunter reports financial support was provided by Iowa Department of Health and Human Services. Mark K. Santillan reports financial support was provided by National Institutes of Health. If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

The mechanisms for the loss in limb muscle power output in old (60-79 yr) and very old (≥80 yr) adults and whether the mechanisms differ between men and women are not well understood. We compared maximal peak power of the knee extensor muscles between young, old, and very old men and women and identified the neural and muscular factors contributing to the age-related differences in power. Thirty-one young (22.9 ± 3.0 yr, 15 women), 82 old (70.3 ± 4.9 yr, 38 women), and 16 very old adults (85.8 ± 4.2 yr, 9 women) performed maximal isokinetic contractions at 14 different velocities (30-450°/s) to identify peak power. Voluntary activation (VA) and contractile properties were assessed with transcranial magnetic stimulation to the motor cortex and electrical stimulation of the femoral nerve. The age-related loss in peak power was ∼6.5 W·yr -1 for men ( R 2 = 0.62, P < 0.001), which was a greater rate of decline ( P = 0.002) than the ∼4.2 W·yr -1 for women ( R 2 = 0.77, P < 0.001). Contractile properties were the most closely associated variables with peak power for both sexes, such as the rate of torque development of the potentiated twitch (men: R 2 = 0.69, P < 0.001; women: R 2 = 0.57, P < 0.001). VA was weakly associated with power in women ( R 2 = 0.13, P = 0.012) but not in men ( P = 0.191). Similarly, neuromuscular activation [rates of electromyography (EMG) rise] during the maximal power contraction was associated with power in women ( R 2 = 0.07, P = 0.042) but not in men ( P = 0.456). These data suggest that the age-related differences in maximal peak power of the knee extensor muscles are due primarily to factors within the muscle for both sexes, although neural factors may play a minor role in older women. NEW & NOTEWORTHY The greater age-related loss in power relative to the loss in muscle mass of the knee extensors was primarily due to factors altering the contractile properties of the muscle for both old and very old (≥80 yr) adults. The mechanisms for the decrements in power with aging appear largely similar for men and women, although neural factors may play more of a role in older women.

Sex as a biological variable is an underappreciated aspect of biomedical research, with its importance emerging in more recent years. This review assesses the current understanding of sex differences in human physical performance. Males outperform females in many physical capacities because they are faster, stronger and more powerful, particularly after male puberty. This review highlights key sex differences in physiological and anatomical systems (generally conferred via sex steroids and puberty) that contribute to these sex differences in human physical performance. Specifically, we address the effects of the primary sex steroids that affect human physical development, discuss insight gained from an observational study of 'real-world data' and elite athletes, and highlight the key physiological mechanisms that contribute to sex differences in several aspects of physical performance. Physiological mechanisms discussed include those for the varying magnitude of the sex differences in performance involving: (1) absolute muscular strength and power; (2) fatigability of limb muscles as a measure of relative performance; and (3) maximal aerobic power and endurance. The profound sex-based differences in human performance involving strength, power, speed and endurance, and that are largely attributable to the direct and indirect effects of sex-steroid hormones, sex chromosomes and epigenetics, provide a scientific rationale and framework for policy decisions on sex-based categories in sports during puberty and adulthood. Finally, we highlight the sex bias and problem in human performance research of insufficient studies and information on females across many areas of biology and physiology, creating knowledge gaps and opportunities for high-impact studies., (© 2024 The Author(s). The Journal of Physiology published by John Wiley & Sons Ltd on behalf of The Physiological Society.)

Impaired cerebral inhibition is commonly observed in neurodevelopmental disorders and may represent a vulnerability factor for their development. The hippocampus plays a key role in inhibition among adults and undergoes significant and rapid changes during early brain development. Therefore, the structure represents an important candidate region for early identification of pathology that is relevant to inhibitory dysfunction. To determine whether hippocampal function corresponds to inhibition in the early postnatal period, the present study evaluated relationships between hippocampal activity and sensory gating in infants 4-20 weeks of age (N = 18). Resting-state functional magnetic resonance imaging was used to measure hippocampal activity, including the amplitude of low-frequency fluctuations (ALFFs) and fractional ALFF. Electroencephalography during a paired-stimulus paradigm was used to measure sensory gating (P50). Higher activity of the right hippocampus was associated with better sensory gating (P50 ratio), driven by a reduction in response to the second stimulus. These findings suggest that meaningful effects of hippocampal function can be detected early in infancy. Specifically, higher intrinsic hippocampal activity in the early postnatal period may support effective inhibitory processing. Future work will benefit from longitudinal analysis to clarify the trajectory of hippocampal function, alterations of which may contribute to the risk of neurodevelopmental disorders and represent an intervention target., (© 2024 Wiley Periodicals LLC.)

Purpose: To understand athletic performance before and after puberty, this study determined 1) the age at which the sex difference increases among elite youth track and field athletes for running and jumping events, and 2) whether there is a sex difference in performance before ages associated with puberty among elite youth athletes., Methods: Track and field records of elite US male and female youth (7-18 yr) across 3 yr (2019, 2021, and 2022) were collected from an online database ( athletic.net ). The top 50 performances were recorded for 100-, 200-, 400-, and 800-m track running, long jump, and high jump., Results: Males ran faster than females at every age in the 100, 200, 400 and 800 m ( P < 0.001). When combining all running events, the sex difference (%) was 4.0% ± 1.7% between 7 and 12 yr and increased to 6.3% ± 1.1% at 13 yr and 12.6% ± 1.8% at 18 yr ( P < 0.001). Similarly, males jumped higher and farther than females at every age ( P < 0.001). For long jump, the sex difference was 6.8% ± 2.8% between 7 and 12 yr, increasing to 8.5% ± 1.7% at 13 yr and 22.7% ± 1.4% at 18 yr ( P < 0.001). For high jump, the sex difference was 5.3% ± 5.2% between 7 and 12 yr, increasing to 12.4% ± 2.9% at 15 yr and 18.4% ± 2.04% at 18 yr ( P < 0.001)., Conclusions: Before 12 yr of age in elite youth track and field athletes, there was a consistent and significant sex difference of ~5%, such that males ran faster and jumped higher and farther than females. The magnitude of the sex difference in performance increased markedly at 12-13 yr for running and long jump and 14 yr for high jump and thus was more pronounced after ages associated with puberty., (Copyright © 2024 by the American College of Sports Medicine.)

Force steadiness can be influenced by visual feedback as well as presence of a cognitive tasks and potentially differs with age and sex. This study determined the impact of altered visual feedback on force steadiness in the presence of a difficult cognitive challenge in young and older men and women. Forty-nine young (19-30 yr; 25 women, 24 men) and 25 older (60-85 yr; 15 women; 10 men) performed low force (5% of maximum) static contractions with the elbow flexor muscles in the presence and absence of a cognitive challenge (counting backwards by 13) either with low or high visual feedback gain. The cognitive challenge reduced force steadiness (increased force fluctuation amplitude) particularly in women (cognitive challenge × sex: P < 0.05) and older individuals (cognitive challenge × age: P < 0.05). Force steadiness improved with high-gain visual feedback compared with low-gain visual feedback (P < 0.01) for all groups (all interactions: P > 0.05). Manipulation of visual feedback had no influence on the reduced force steadiness in presence of the cognitive challenge for all groups (all P > 0.05). These findings indicate that older individuals and women have greater risk of impaired motor performance of the upper extremity if steadiness is required during a low-force static contraction. Manipulation of visual feedback had minimal effects on the reduced force steadiness in presence of a difficult cognitive challenge., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Sports participation confers many health benefits yet greatly increases injury risk. Long-term health outcomes in former athletes and transition to life after competitive sports are understudied. Ending a sport may pose physical and psychosocial challenges. The purpose was to determine the lived experiences of former competitive athletes and how their sports participation impacted their long-term health and well-being. Former college varsity athletes participated in semistructured interviews focusing on their experiences, including past and current health, the impact of injuries, activity, exercise, diet and transition to life after competitive sport. Thematic analysis was completed using a collaborative, iterative process. Thirty-one (16 female, 15 male) former college athletes aged 51.3±7.4 years were interviewed. Six themes emerged: (1) lifelong athlete identity; (2) structure, support and challenges of the college athlete experience; (3) a big transition to life beyond competitive sport; (4) impact of competitive sport on long-term health; (5) facilitators and barriers to long-term health after sport and (6) transferable life skills. Continuing sports eased the transition for many but often delayed their postathlete void. Challenges included managing pain and prior injury (eg, If I didn't have my knee injury, I would definitely be more active ), reducing energy needs and intake (eg, When I was an athlete, I could eat anything; and unfortunately, that's carried into my regular life), lack of accountability, changed identity and lost resources and social support. Participants suggested a programme, toolkit, mentoring or exit course to facilitate the transition. While former athletes benefit from transferrable life skills and often continue sports and exercise, they face unique challenges such as managing pain and prior injury, staying active, reducing energy intake and changing identity. Future research should develop and evaluate a toolkit, programme and other resources to facilitate life after ending competitive sports under 'normal' conditions (eg, retirement) and after a career-ending injury., Competing Interests: Competing interests: The authors have nothing to disclose except for grant funding as acknowledged above., (© Author(s) (or their employer(s)) 2024. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

High-level athletic performances may be a proxy for the trajectory of optimal function of human biology with advanced aging and the differences between males and females. Males are faster, stronger, and more powerful than females and these physical attributes decline dramatically with advanced aging for both sexes. Experimental mechanistic studies determine the physiological mechanisms for these sex and age differences in human physical performance. The assumption however, that real-world performances solely reflect the biological and physiological differences between the sexes and with advanced aging, even among elite athletes, is not complete. This review presents evidence that an integrated approach encompassing analysis of real-world data and experimental mechanistic studies is necessary to determine the biological and sociocultural factors attributed to the limits of performance with aging and between males and females. First, experimental studies are presented that focus on the sex and age differences in performance fatigability that determine the physiological mechanisms of absolute and relative exercise performance. Second, analysis of current and historical real-world data including world records, and performances of elite, collegiate, and competitive age-group athletes are highlighted. These data illustrate that the upper limits of physical performance that have changed historically, and other factors such as sociocultural influences, explain the widening of the sex and age gaps in human performance observed in real-world data even in present-day performances. These approaches have broader significance when applied to understanding the impact of the historically low representation of females and minority groups in biomedical research on health outcomes.

Biological sex is a primary determinant of athletic human performance involving strength, power, speed, and aerobic endurance and is more predictive of athletic performance than gender. This perspective article highlights 3 key medical and physiological insights related to recent evolving research into the sex differences in human physical performance: (1) sex and gender are not the same; (2) males and females exhibit profound differences in physical performance with males outperforming females in events and sports involving strength, power, speed, and aerobic endurance; (3) endogenous testosterone underpins sex differences in human physical performance with questions remaining on the roles of minipuberty in the sex differences in performance in prepubescent youth and the presence of the Y chromosome (SRY gene expression) in males, on athletic performance across all ages. Last, females are underrepresented as participants in biomedical research, which has led to a historical dearth of information on the mechanisms for sex differences in human physical performance and the capabilities of the female body. Collectively, greater effort and resources are needed to address the hormonal mechanisms for biological sex differences in human athletic performance before and after puberty., (© The Author(s) 2024. Published by Oxford University Press on behalf of the Endocrine Society. All rights reserved. For commercial re-use, please contact reprints@oup.com for reprints and translation rights for reprints. All other permissions can be obtained through our RightsLink service via the Permissions link on the article page on our site—for further information please contact journals.permissions@oup.com.)

The clinical care of infants born at 22 weeks' gestation must be well-designed and standardized if optimal results are to be expected. Although several approaches to care in this vulnerable population are possible, protocols should be neither random nor inconsistent. We describe the approach taken at the University of Iowa Stead Family Children's Hospital neonatal intensive care unit with respect to preterm infants born at 22 weeks' gestation. We have chosen to present our standardize care plan with respect to prenatal, neurologic, nutritional, gastrointestinal, and skin management. Respiratory and cardiopulmonary care will be briefly reviewed, as these strategies have been published previously., (Copyright © 2023 Elsevier Inc. All rights reserved.)

Choline and folate are critical nutrients for fetal brain development, but the timing of their influence during gestation has not been previously characterized. At different periods during gestation, choline stimulation of α7-nicotinic receptors facilitates conversion of γ-aminobutyric acid (GABA) receptors from excitatory to inhibitory and recruitment of GluR1-R2 receptors for faster excitatory responses to glutamate. The outcome of the fetal development of inhibition and excitation was assessed in 159 newborns by P50 cerebral auditory-evoked responses. Paired stimuli, S1, S2, were presented 500 msec apart. Higher P50 amplitude in response to S1 (P50 S1 microV) assesses excitation, and lower P50 S2 microV assesses inhibition in this paired-stimulus paradigm. Development of inhibition was related solely to maternal choline plasma concentration and folate supplementation at 16 weeks' gestation. Development of excitation was related only to maternal choline at 28 weeks. Higher maternal choline concentrations later in gestation did not compensate for earlier lower concentrations. At 4 years of age, increased behavior problems on the Child Behavior Checklist 1½-5yrs were related to both newborn inhibition and excitation. Incomplete development of inhibition and excitation associated with lower choline and folate during relatively brief periods of gestation thus has enduring effects on child development., Competing Interests: Conflict of interest disclosure: Angelo D’Alessandro is a founder and Chief Scientific Officer of Omix Technologies, Inc. and Altis Biosciences, and Scientific Advisory Board member of Hemanext Inc. These companies were not involved in this study. The other authors declare no competing financial interests.

Introduction: Adverse childhood experiences (ACEs) are a measure of childhood adversity and are associated with life-long morbidity. The impacts of ACEs on peripartum health including preeclampsia, a common and dangerous hypertensive disorder of pregnancy, remain unclear, however. Therefore, we aimed to determine ACE association with peripartum psychiatric health and prevalence of preeclampsia using a case-control design., Methods: Clinical data were aggregated and validated using a large, intergenerational knowledgebase developed at our institution. Depression symptoms were measured by standard clinical screeners: the Patient Health Questionnaire-9 (PHQ-9) and the Edinburgh Postnatal Depression Scale (EPDS). ACEs were assessed via survey. Scores were compared between participants with ( N = 32) and without ( N = 46) prior preeclampsia., Results: Participants with ACE scores ≥4 had significantly greater odds of preeclampsia than those with scores ≤ 3 (adjusted odds ratio = 6.71, 95% confidence interval:1.13-40.00; p = 0.037). Subsequent speculative analyses revealed that increased odds of preeclampsia may be driven by increased childhood abuse and neglect dimensions of the ACE score. PHQ-9 scores (3.73 vs. 1.86, p = 0.03), EPDS scores (6.38 vs. 3.71, p = 0.01), and the incidence of depression (37.5% vs. 23.9%, p = 0.05) were significantly higher in participants with a history of preeclampsia versus controls., Conclusions: Childhood sets the stage for life-long health. Our findings suggest that ACEs may be a risk factor for preeclampsia and depression, uniting the developmental origins of psychiatric and obstetric risk., Competing Interests: None., (© The Author(s) 2024.)

Reduced heart rate variability (HRV) and fatigue are common after COVID-19 infection and both are potentially influenced by physical activity (PA). We compared resting HRV, PA from accelerometers and questionnaires, and self-reported fatigue in 41 COVID-19 survivors (~8 months postinfection, 38 ± 17 years) with 41 matched controls. Differences in HRV were observed on acceleration capacity (p = 0.041), deceleration capacity (p = 0.032), high-frequency peak frequency (p = 0.019), absolute low-frequency power (p = 0.042), relative very low-frequency power (p = 0.012), SD2 (from Poincare plot; p = 0.047), and DFA2 (slope of long-term detrended fluctuation analysis; p = 0.004). Fatigue was greater in COVID-19 survivors (p < 0.001) with no differences in PA. Moderate-vigorous physical activity (MVPA) (Standardized Beta = -0.427, p = 0.003) and steps per day (Standardized Beta = -0.402, p = 0.007) were associated with DFA2 in COVID-19 survivors after controlling for age, sex, and body fat percentage. Fatigue was correlated to less MVPA (Spearman's rho = 0.342, p = 0.031) and fewer steps per day (rho = 0.329, p = 0.038) in COVID-19 survivors, and was indirectly linked to HRV through these PA mediators (Estimate = -0.20; p = 0.040). We present a model showing the complex relations between HRV, PA, and fatigue that provides the foundation for strategies to improve outcomes and rehabilitation after COVID-19 infection., (© 2024 The Authors. Physiological Reports published by Wiley Periodicals LLC on behalf of The Physiological Society and the American Physiological Society.)

ABSTRACT Females demonstrate greater fatigue resistance compared to males in tasks ranging from single-limb contractions to whole-body exercise, including running. Many of the studies investigating sex differences in fatigability following running, however, occur after long duration, low-intensity tasks and it is unknown whether there is a sex difference in fatigability following high-intensity running. This study compared fatigability and recovery following a 5 km running time trial in young males and females. Sixteen recreationally active participants (8 males, 8 females, age: 23 ± 4 years) completed a familiarisation and experimental trial. Knee-extensor maximal voluntary contractions (MVCs) were performed before and up to 30 min after a 5 km time trial on a treadmill. Heart rate and rating of perceived exertion (RPE) were recorded after every kilometre during the time trial. Although not significantly different, males completed the 5 km time trial 15% faster than females ( p =  0.095). Heart rate ( p  = 0.843) and RPE ( p  = 0.784) were similar between the sexes during the trial. Prior to running, males had larger MVCs ( p  = 0.014). The relative decrease in MVC force was less in females than males immediately post-exercise (-4.6 ± 2.4% vs. -15.1 ± 3.0%, p  < 0.001) and at 10-minutes post-exercise ( p  = 0.018). At 20- and 30-minutes recovery, however, relative MVC force was not different between the sexes ( p  ≥ 0.129). These data demonstrate that females experienced less fatigability of the knee extensors than males following a high-intensity 5 km running time trial. The findings highlight the need to understand responses to exercise in both sexes and have implications for recovery from training and exercise prescription. Highlights Data regarding sex differences in fatigability following high-intensity running is relatively sparse.Therefore, this study quantified the decrease in knee-extensor maximum voluntary contraction force (MVC) following a 5-km self-paced running time trial.Despite similar heart rates and ratings of perceived exertion, the percentage decrease in MVC was three times greater in males compared to females.Relative MVCs remained greater in females compared to males until 20 min post-exercise.

Abstract: Biological sex is a primary determinant of athletic performance because of fundamental sex differences in anatomy and physiology dictated by sex chromosomes and sex hormones. Adult men are typically stronger, more powerful, and faster than women of similar age and training status. Thus, for athletic events and sports relying on endurance, muscle strength, speed, and power, males typically outperform females by 10%-30% depending on the requirements of the event. These sex differences in performance emerge with the onset of puberty and coincide with the increase in endogenous sex steroid hormones, in particular testosterone in males, which increases 30-fold by adulthood, but remains low in females. The primary goal of this consensus statement is to provide the latest scientific knowledge and mechanisms for the sex differences in athletic performance. This review highlights the differences in anatomy and physiology between males and females that are primary determinants of the sex differences in athletic performance and in response to exercise training, and the role of sex steroid hormones (particularly testosterone and estradiol). We also identify historical and nonphysiological factors that influence the sex differences in performance. Finally, we identify gaps in the knowledge of sex differences in athletic performance and the underlying mechanisms, providing substantial opportunities for high-impact studies. A major step toward closing the knowledge gap is to include more and equitable numbers of women to that of men in mechanistic studies that determine any of the sex differences in response to an acute bout of exercise, exercise training, and athletic performance., (Copyright © 2023 by the American College of Sports Medicine.)

While sports medicine has traditionally focused on recovering from injury and returning athletes to sport safely after injury, there is a growing interest in the long-term health of athletes. The purpose of this scoping review was to (1) summarise the literature (methodologies and findings) on physical function, body composition and cardiometabolic health in midlife (age 40-65 years) former competitive athletes compared with non-athlete controls, (2) identify areas for future study in long-term health in athletes and (3) determine outcomes that could be evaluated in a future systematic review(s). We searched PubMed, CINAHL, Web of Science and SPORTDiscus for studies published between 2000 and 2022 evaluating former athletes and controls on physical function, body composition and/or cardiometabolic measures using MeSH terms. We identified 20 articles that met our criteria. Outcomes varied considerably across studies, most of which were cross-sectional and evaluated only males. Limited data suggest that former endurance athletes have leaner body compositions, higher aerobic capacity and better cardiometabolic indicators than controls; former athletes who maintain higher physical activity (ie, self-reported exercise) are healthier than those who do not; and former team sport athletes, who have higher injury prevalence, may have poorer functional performance than controls who were recreationally active in college. Studies rarely evaluated functional performance, did not control for prior injury or diet and seldom assessed current physical activity levels. Future research should include females and evaluate sex differences, control for prior sports-related injury(ies), quantify physical activity, use standardised outcome measures including performance-based functional assessments and incorporate longitudinal designs., Competing Interests: Competing interests: Funding for this work was provided by an NIH Director’s Early Independence Award to JJC (DP5-OD031833)., (© Author(s) (or their employer(s)) 2023. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

Historically, low representation of women participants in exercise science and physiology studies has led to a lack of understanding in the response of women to exercise and therapeutic interventions. We hypothesized that 1 ) the number of women authors, participants, and editorial board members increased over 30 years (1991-2021) and 2 ) larger representation of women as editors and authors is associated with more women participants. Gender (man/woman) of editorial board members ( n = 394), authors ( n = 5,735), and participants ( n = 2,984,883) of 972 original research articles with human participants published in 1991 and 2021 was analyzed from three journals: Journal of Applied Physiology , Medicine and Science in Sports and Exercise , and British Journal of Sports Medicine . Between 1991 to 2021, the average percent women per article as participants (21.9 ± 31.7% vs. 36.3 ± 30.3%, respectively, P < 0.001), authors (16.4 ± 22.4% vs. 30.9 ± 24.0%, P < 0.001), and editorial board members (13.3 ± 5.4% vs. 41.5 ± 7.3%, P = 0.006) increased. In 2021, the gender proportion of participants in large datasets was similar (50.2 ± 20.2% women). However, studies with smaller datasets (i.e., <∼3,000 participants) included less women (35.6 ± 30.6%). Women participants (%) were less when the last author was a man rather than a woman in 1991 (19.9 ± 29.5% vs. 34.3 ± 42.2%) and 2021 (31.6 ± 27.7% vs. 51.7 ± 33.4%). In 2021, there was a positive correlation between author and participant gender (% women) ( r = 0.42, P < 0.001). Our data suggest that the low representation of women in exercise science and physiology research could be resolved with equitable numbers of women authors and editors and by encouraging men authors to study both women and men participants. NEW & NOTEWORTHY Analysis of human applied physiology studies revealed that the representation of women authors, participants, and editorial board members increased over 30 years but remained lower than men in 2021. Larger representation of women editors and authors was associated with more women participants. Women authors assessed similar numbers of women and men participants, whereas men authors included less women. Equitable representation of women participants may be achieved by closing the gender gap in authorship and editorial board membership.

Introduction/purpose: The purpose of this study was to determine the following in persons with midportion Achilles tendinopathy (AT): 1) maximal strength and power; 2) neural drive during maximal contractions and contractile function during electrically evoked resting contractions; and 3) whether pain, neural drive, and contractile mechanisms contribute to differences in maximal strength., Methods: Twenty-eight volunteers (14 AT, 14 controls) completed isometric, concentric, and eccentric maximal voluntary contractions (MVCs) of the plantar flexors in a Biodex ™ dynamometer. Supramaximal electrical stimulation of the tibial nerve was performed to quantify neural drive and contractile properties of the plantar flexors. Pain sensitivity was quantified as the pressure-pain thresholds of the Achilles tendon, medial gastrocnemius, and upper trapezius., Results: There were no differences in plantar flexion strength or power between AT and controls (isometric MVC: P = 0.95; dynamic MVC: P = 0.99; power: P = 0.98), nor were there differences in neural drive and contractile function ( P = 0.55 and P = 0.06, respectively). However, the mechanisms predicting maximal strength differed between groups: neural drive predicted maximal strength in controls ( P = 0.02) and contractile function predicted maximal strength in AT ( P = 0.001). Although pain did not mediate these relationships (i.e., between maximal strength and its contributing mechanisms), pressure-pain thresholds at the upper trapezius were higher in AT ( P = 0.02), despite being similar at the calf ( P = 0.24) and Achilles tendon ( P = 0.40)., Conclusions: There were no deficits in plantar flexion strength or power in persons with AT, whether evaluated isometrically, concentrically, or eccentrically. However, the mechanisms predicting maximal plantar flexor strength differed between groups, and systemic pain sensitivity was diminished in AT., Competing Interests: CONFLICT OF INTEREST AND SOURCE OF FUNDING There are no conflicts of interest to report.

Introduction: The cumulative number of COVID-19 cases has surpassed 579 million globally. Symptoms during and after COVID-19 infection vary from mild cold symptoms to severe multisystem illness. Given the wide range of symptom presentations and complications post-COVID-19, the purpose of this study was to describe the lived experience of American adults surviving COVID-19., Method: This study employed an exploratory qualitative description design. Semi-structured interviews were conducted with a sample of 35 individuals (White [94%], female [71%], M age = 43.7 years), with proximity to a university in an urban Midwest American city. Interviews occurred between May and August 2021, 3 or more months after participants tested positive for COVID-19., Results: Forty percent of the 35 participants experienced prolonged COVID-19 symptoms impacting their lifestyle. Four themes characterized the impacts of the post-COVID-19 condition on the lives of the participants within the context of a global pandemic: (a) disruptions in health and well-being, (b) persistent uncertainty, (c) disruptions in interpersonal relationships, (d) beneficent outcomes and adaptation., Discussion: This study of COVID-19 has identified important implications for physical activity and interpersonal stress. Prolonged COVID-19 symptoms led to disruptions in the health, well-being, and interpersonal relationships of participants. Health care professionals need to attend to symptoms post-COVID-19, assess interpersonal functioning, and provide guidance on physical activity. Future studies are recommended to track consequences of COVID-19's impact on long-term health and well-being. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

Objective: Exercise is recommended as a main treatment in fibromyalgia. However, many people have limited exercise tolerance and report exacerbated pain and fatigue during and following a bout of exercise. This study examined the local and systemic changes in perceived pain and fatigue during exercise and through the 3-day recovery following isometric and concentric exercises in people with and without fibromyalgia., Methods: Forty-seven participants with a physician diagnosis of fibromyalgia (44 women; mean age [SD] = 51.3 [12.3] years; mean body mass index [SD] = 30.2 [6.9]) and 47 controls (44 women; mean age [SD] = 52.5 [14.7] years; mean body mass index [SD] = 27.7 [5.6]) completed this prospective, observational cohort study. A bout of submaximal resistance exercise (isometric and concentric) was performed localized to the right elbow flexors on 2 separate days. Baseline attributes (pain, fatigue, physical function, physical activity, and body composition) were assessed prior to exercise. Primary outcomes were: change in perceived pain and fatigue (0 to 10 on the visual analog scale) in the exercising limb and whole body during recovery with movement (immediately, 1 day following exercise, and 3 days following exercise). Secondary outcomes were perceived pain and exertion during exercise performance and pain and fatigue at rest during recovery., Results: Following a single bout of isometric or concentric exercise, there was increased perceived pain (ηp2 = 0.315) and fatigue (ηp2 = 0.426) in the exercising limb, which was greater in people with fibromyalgia (pain: ηp2 = 0.198; fatigue: ηp2 = 0.211). Clinically, relevant increases in pain and fatigue during exercise and through the 3-day recovery occurred in individuals with fibromyalgia only. Concentric contractions led to greater perceived pain, exertion, and fatigue during exercise compared with isometric exercise for both groups., Conclusions: People with fibromyalgia experienced significant pain and fatigue in the exercising muscle during recovery from low-intensity and short-duration resistance exercise, with greater pain during concentric contractions., Impact: These findings highlight a critical need to assess and manage pain and fatigue in the exercising muscles of people with fibromyalgia up to 3 days following a single bout of submaximal resistance exercise., Lay Summary: If you have fibromyalgia, you might have significant pain and fatigue up to 3 days following an exercise bout, with the pain and fatigue localized to the exercising muscles and no changes in whole-body pain., (© The Author(s) 2023. Published by Oxford University Press on behalf of the American Physical Therapy Association. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Despite activities of daily living being frequently performed simultaneously with a cognitive task, motor function is often investigated in isolation, which can hinder the applicability of findings. This brief review presents evidence that 1) performing a cognitive challenge simultaneously with a motor task can negatively impact force steadiness and fatigability of limb muscles during a static contraction, 2) the negative impact on old adults (>65 years old), particularly older women is greater than young when a cognitive challenge is simultaneously performed with a static motor task, 3) age-related mechanisms potentially explain impairments in motor performance in the presence of a cognitive challenge, and 4) the mechanisms for the age-related decrements in motor performance can be distinct between men and women. These observations are highly relevant to the older adults, given the increased risk of accidents and injury when a motor task is performed with a high cognitive-demand task, especially in light of the expanding reliance on an aging workforce., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Pereira and Hunter.)

Purpose: To determine if the speed-duration relationship is altered with age and sex of elite Master's runners., Methods: The world's top 10 performances for men and women in three events (800, 1500, and 5000 m) across six age groups (18-34 yr, 40-49 yr, 50-59 yr, 60-69 yr, 70-79 yr, and 80-89 yr) were analyzed from public data to establish theoretical models of the speed-duration relationship. Critical speed (CS) and the curvature constant ( D ') were estimated by fitting the average speeds and performance times with a two-parameter hyperbolic model., Results: Critical speed expressed relative to the 18- to 34-yr-olds, declined with age (92.2% [40-49] to 55.2% [80-89]; P < 0.001), and absolute CS was higher in men than women within each age group ( P < 0.001). The percent difference in CS between the men and women progressively increased across age groups (10.8% [18-34] to 15.5% [80-89]). D ' was lower in women than men in the 60-69 yr, 70-79 yr, and 80-89 yr age groups ( P < 0.001), but did not differ in the 18-34 yr, 40-49 yr, or 50-59 yr age groups., Conclusions: Critical speed progressively decreased with age, likely due to age-related decrements in several physiological systems that cause reduced aerobic capacity. The mechanism for the larger sex difference in CS in the older age groups is unknown but may indicate physiological differences that occur with aging and/or historical sociological factors that have reduced participation opportunities of older female runners resulting in a more limited talent pool., (Copyright © 2022 by the American College of Sports Medicine.)

There is current scientific and legal controversy about sports competition eligibility regulations for transgender athletes. In this case study, we quantified performances by an elite, transgender woman (male sex, female gender identity) college swimmer who competed in both the men's and women's National Collegiate Athletic Association (NCAA) categories. We also contextualized her performances with respect to world-record performances and contemporary elite college swimmers. These data demonstrate that the declines in freestyle swimming performances of a transgender woman after about 2 yr of reported feminizing gender-affirming hormone treatment (0.5% for the 100 to 7.3% for the 1,650 yard distance) are smaller than the observed sex-related differences in performance of top 200 world record performances in metric distances of similar durations (11.4% for the 100 m to 9.3% for the 1,500 m distance). Despite slower performances, the transgender woman swimmer experienced improvements in performance for each freestyle event (100 to 1,650 yards) relative to sex-specific NCAA rankings, including producing the best swimming time in the NCAA for the 500-yard distance (65 th in the men's category in 2018-2019 to 1 st in the women's, 2022). Similarly, NCAA-ranked male swimmers had no improvements in rank in the men's category during the same time frame. Our findings suggest that the performance times of the transgender woman swimmer in the women's NCAA category were outliers for each event distance and suggest that the transgender woman swimmer had superior performances relative to rank-matched swimmers. Our analysis may be useful as a framework for regulators considering participation guidelines, which promote fair competition for all athletes-irrespective of gender identity. NEW & NOTEWORTHY This case study, longitudinal analysis of freestyle swimming performances before and after 2 yr of feminizing gender-affirming hormone therapy of an elite transgender woman (male sex, female gender identity), demonstrates superior performance relative to rank-matched female swimmers and a lower performance gap than previously observed between elite male and female swimmers.

Increasing hospital and labor & delivery (L&D) closures have led to declining access to hospital obstetric care in rural areas across the country. These closures increase the burden on women and families living in rural communities, who often must drive long distances for prenatal visits and delivery. The lack of maternal health care in rural America can also result in several adverse maternal and infant outcomes including premature birth, low birth weight, out of hospital births, maternal and infant morbidity and mortality, and increased risk of postpartum depression. The reasons for these closures are multifactorial, and include, workforce shortages, financial viability, low volume of patients, concerns over maintaining the knowledge base and skill sets of the obstetrical health care team required to provide high quality and safe care, as well as medical-legal concerns. The problems of providing and accessing quality maternal and obstetrical care in rural America have not happened overnight, Likewise, the solutions to these problems will also not occur overnight and must also address the multifactorial nature of the problem. However, there are several opportunities to improve access to maternal health care in rural communities. Programs, policies, and funding need to be designed and provided to make these opportunities a reality., (Copyright © 2022 Wolters Kluwer Health, Inc. All rights reserved.)

Background: Prenatal choline is a key nutrient, like folic acid and vitamin D, for fetal brain development and subsequent mental function. We sought to determine whether effects of higher maternal plasma choline concentrations on childhood attention and social problems, found in an initial clinical trial of choline supplementation, are observed in a second cohort., Methods: Of 183 mothers enrolled from an urban safety net hospital clinic, 162 complied with gestational assessments and brought their newborns for study at 1 month of age; 83 continued assessments through 4 years of age. Effects of maternal 16 weeks of gestation plasma choline concentrations ⩾7.07 μM, 1 s.d. below the mean level obtained with supplementation in the previous trial, were compared to lower levels. The Attention Problems and Withdrawn Syndrome scales on Child Behavior Checklist 1½-5 were the principal outcomes., Results: Higher maternal plasma choline was associated with lower mean Attention Problems percentiles in children, and for male children, with lower Withdrawn percentiles. Higher plasma choline concentrations also reduced Attention Problems percentiles for children of mothers who used cannabis during gestation as well as children of mothers who had gestational infection., Conclusions: Prenatal choline's positive associations with early childhood behaviors are found in a second, more diverse cohort. Increases in attention problems and social withdrawal in early childhood are associated with later mental illnesses including attention deficit disorder and schizophrenia. Choline concentrations in the pregnant women in this study replicate other research findings suggesting that most pregnant women do not have adequate choline in their diets.

Choline, folic acid, and Vitamin D are essential for fetal brain development that may be the first steps in the pathogenesis of the psychotic spectrum. Micronutrient deficiencies have been associated with changes in fetal brain development, manifest as early problems in childhood behavior, and cognition, and later as increased incidence of psychotic and autism spectrum disorders. Micronutrient supplements may not only prevent deficiency, but they may also positively affect brain development in the context of other maternal risk factors, including maternal infection, stress, inflammation, and substance abuse. Many genes associated with later psychotic illness are highly expressed in the fetal brain, where they are responsible for various neurodevelopmental mechanisms. Interaction of micronutrient vitamins with these genetically programmed mechanisms to prevent pathological brain development associated with later psychosis is under active investigation. In addition to their effects on brain development, micronutrient vitamins have effects on other aspects of gestation and fetal development, including the prevention of premature delivery and other developmental abnormalities. Supplemental micronutrient vitamins should be part of good prenatal care, as has already happened for folic acid and Vitamin D and is now advocated by the American Medical Association for choline. The benefits of these micronutrient supplements include protection of brain development and the possibility of decreased risk for future psychotic disorders in those children who are either genetically or environmentally vulnerable. The purpose of this review is to present the current evidence supporting the safety and effectiveness of micronutrients in gestation and to suggest areas for future research., Competing Interests: Declaration of competing interest The authors report no conflict of interest., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Introduction: Pregnancy is a time of increased healthcare screening, and past adherence to evolving guidelines informs best practices. Although studies of Group B Streptococcus guideline adherence have focused primarily on treatment of Group B Streptococcus carriers, this study broadly evaluated long-term adherence to both Group B Streptococcus screening and treatment guidelines. Adherence was evaluated across provider types (obstetrics and gynecology, certified nurse midwives, and family medicine)., Methods: We conducted a retrospective cohort study. Demographic and clinical information were extracted from all prenatal care and delivery patients at a single institution in a single year. Vancomycin prescriptions in pregnancy were tracked for 10 years to determine long-term adherence. Adherence was defined as no deviation from 2010 Group B Streptococcus screening and treatment guidelines., Results: Adherence occurred in 89% (1,610/1,810) of patients. Reasons for deviations from guidelines could not always be determined. There was no significant difference in maternal age, race, prenatal provider type, provider type at delivery, gestational age at delivery, delivery mode, or whether antibiotic sensitivities were performed between compliant and noncompliant groups. Significant differences in adherence were found between obstetric clinics (high-risk obstetrics clinic, maternal‒fetal medicine fellows clinic, continuity of care clinic, and faculty private clinic) ( p <0.0001) and between the faculty family medicine clinic and resident family medicine clinic ( p =0.001). Vancomycin prescription practice did not change significantly over the10-year period., Conclusions: High rates of adherence to Group B Streptococcus screening and treatment guidelines in pregnancy have positive implications for reducing antibiotic resistance. Given evolving guidelines, there is a need to periodically evaluate adherence and to re-educate providers about standard practices and best documentation practices., (© 2022 The Author(s).)

To advance the application of clinical data to address maternal health we developed and implemented a Maternal Child Knowledgebase (MCK). The MCK integrates data from every pregnancy that received care at the University of Iowa Hospitals & Clinics (UIHC) and links information from the pregnancy episode to the delivery episode and between the mother and child. This knowledgebase contains integrated information regarding diagnoses, medications, mother and child vitals, hospital admissions, depression screenings, laboratory value results, and procedure information. It also collates information from the electronic health record (EPIC), the Social Security Death Index, and the Medication Administration Record into one knowledgebase. To enhance usability, we designed a custom viewer with several pre-designed queries and reports that eliminates the need for users to be proficient in SQL coding. The recent implementation of the MCK has supported multiple projects and reduced the number of Obstetrics-related data queries to the Biomedical Informatics group., (©2022 AMIA - All rights reserved.)

The approach to clinical care of infants born at 22 weeks' gestation must be consistent and well-designed if optimal results are to be expected. Publications from several international centers have demonstrated that, although there may be variance in aspects of care in this vulnerable population, treatment should be neither random nor inconsistent. In designing a standardized approach, careful attention should be paid to the unique anatomy, physiology, and biochemistry of this vulnerable patient population. Emerging evidence, suggesting a link between cardiopulmonary health and longer-term sequela, highlights the importance of understanding the relationship between cardiorespiratory illnesses of the 22-week infant, treatments provided, and subsequent cardiopulmonary development. In this review we will provide an overview to our approach to cardiopulmonary assessment and treatment, with a particular emphasis on the importance of early recognition of atypical phenotypes, timely interventions with evidence-based treatments, and longitudinal monitoring., (Copyright © 2021 Elsevier Inc. All rights reserved.)

Introduction: To improve maternal health outcomes, increased diversity is needed among pregnant people in research studies and community surveillance. To expand the pool, we sought to develop a network encompassing academic and community obstetrics clinics. Typical challenges in developing a network include site identification, contracting, onboarding sites, staff engagement, participant recruitment, funding, and institutional review board approvals. While not insurmountable, these challenges became magnified as we built a research network during a global pandemic. Our objective is to describe the framework utilized to resolve pandemic-related issues., Methods: We developed a framework for site-specific adaptation of the generalized study protocol. Twice monthly video meetings were held between the lead academic sites to identify local challenges and to generate ideas for solutions. We identified site and participant recruitment challenges and then implemented solutions tailored to the local workflow. These solutions included the use of an electronic consent and videoconferences with local clinic leadership and staff. The processes for network development and maintenance changed to address issues related to the COVID-19 pandemic. However, aspects of the sample processing/storage and data collection elements were held constant between sites., Results: Adapting our consenting approach enabled maintaining study enrollment during the pandemic. The pandemic amplified issues related to contracting, onboarding, and IRB approval. Maintaining continuity in sample management and clinical data collection allowed for pooling of information between sites., Conclusions: Adaptability is key to maintaining network sites. Rapidly changing guidelines for beginning and continuing research during the pandemic required frequent intra- and inter-institutional communication to navigate., Competing Interests: The authors have no conflicts of interest to report., (© The Author(s) 2022.)

Resistance exercise training is a cornerstone in preventing age-related declines in muscle mass and strength, and fatigability of limb muscle is important to this adaptive response. It is unknown, however, whether fatigability and the underlying mechanisms differ between different resistance exercise protocols in young and older adults. The purpose of this study was to quantify the fatigability of the knee extensors and identify the mechanisms in 20 young (22.2 ± 1.3 yr, 10 women) and 20 older adults (73.8 ± 5.4 yr, 10 women) elicited by a single session of high- and low-load resistance exercise. One leg completed a high-load protocol with contractions performed as fast as possible (HL-fast, ~80% 1 Repetition Max, 1RM), and the contralateral leg a low-load protocol performed with slow contractions (LL-slow, ~30% 1RM, 6 s concentric, 6 s eccentric). Each exercise involved four sets of eight repetitions. Before and immediately following each set, maximal voluntary isometric contractions (MVC) were performed, and voluntary activation and contractile properties quantified using electrical stimulation. The reduction in MVC was greater following the LL-slow (20%) than the HL-fast (12%, P = 0.004), with no age or sex differences. Similarly, the reduction in the amplitude of the involuntary electrically-evoked twitch was greater in the LL-slow (14%) than the HL-fast (7%, P = 0.014) and correlated with the reduction in MVC (r = 0.546, P < 0.001), whereas voluntary activation decreased only for the LL-slow protocol (5%, P < 0.001). Thus, low-load resistance exercise with slow contractions induced greater fatigability within the muscle than a more traditional high-load resistance protocol for both young and older men and women., (Copyright © 2021 Elsevier Inc. All rights reserved.)

Objective: Maternal depression during gestation is an adverse factor in fetal brain development that manifests in later childhood behavioral problems. Fetal heart rate variability (FHRV) mediated by parasympathetic input is a marker of gestational nervous system development. Biological mediators of adverse effects of maternal depression may involve the mother's corticosteroids; however, links between depression, corticosteroids, and early nervous system development remain inconclusive., Methods: Heart rate was recorded in 23 fetuses by transabdominal Doppler at 28-33 weeks gestation. The SD of interbeat intervals over 20 min assessed FHRV. Maternal depression ratings and hair concentrations of cortisol and cortisone were assayed. An auditory sensory gating paradigm assessed newborn development of cerebral inhibition. Parents rated their infant's temperament characteristics on the Infant Behavior Questionnaire-Revised Short Form (IBQ-R)., Results: Maternal depression was associated with lower FHRV, especially for male fetuses, β = -0.633, P = 0.045. Maternal depression was associated with lower cortisol to total corticosteroids ratios, β = -0.519, P = 0.033. Lower cortisol ratios were associated with decreased FHRV, β = 0.485, P = 0.019. Decreased FHRV was associated with increased newborn sensory gating deficits, β = -0.992, P = 0.035, indicating poorer development of cerebral inhibition. Higher FHRV was related to increased infant IBQ-R self-regulatory behaviors, r = 0.454, P = 0.029., Conclusion: Maternal depression is associated via corticosteroids with decreased development of nervous system control of fetal heart rate. Decreased FHRV indicates developmental alterations in gestation that correlate with altered brain function and subsequent regulatory challenges in early infancy., (Copyright © 2021 Wolters Kluwer Health, Inc. All rights reserved.)

Maternal gestational inflammation from infection, obesity, depression, and adverse childhood experiences negatively affects offspring cognitive development. Choline is a key nutrient in fetal brain development. We investigated whether higher maternal plasma choline concentrations have a positive association with offspring cognition, specifically processing speed, in the presence of inflammation. Forty-eight children were evaluated at 4 years of age. Processing Speed Composite Score on the Wechsler Preschool & Primary Scales of Intelligence was the principal outcome. Maternal C-reactive protein (CRP), a marker of inflammation, and choline plasma concentration had been measured at 16 weeks' gestation. Choline concentrations >7.07μM were compared to lower levels. Mothers with lower choline levels reported more depression and stress. Head circumference was larger for neonates of mothers with higher choline levels. In analyses with maternal CRP, higher maternal choline was associated with higher offspring Processing Speed Composite Scores for both sexes. For males, higher maternal choline competed with the negative association of maternal CRP on Processing Speed. Higher Processing Speed was related to the child's behavioral ratings, with fewer Withdrawn Problems on the Child Behavior Checklist 1 ½-5 years at 4 years and higher Infant Behavior Questionnaire Orienting/Regulation at 3 months of age, consistent with persistent developmental effects. Higher processing speed and decreased problems in social withdrawal are positively associated with prenatal maternal choline. Both lower processing speed and social withdrawal problems are precursors to later mental difficulties. Choline supplementation in pregnancy may mitigate effects of maternal inflammation that contribute to problems in offspring's' cognition and behavior., (Copyright © 2021. Published by Elsevier Ltd.)

Introduction: The single-leg heel raise test (SLHR) is commonly used in clinical settings to approximate plantar flexor strength, yet this is neither validated nor supported physiologically. The purposes of this study were to: determine (1) associations between SLHR repetitions, maximal plantar flexor strength, and reductions in strength; and (2) whether sex differences exist in performance of the SLHR., Methods: Twenty-eight young, healthy participants (14 males,14 females, 19-30 years) performed repeated single-leg heel raises to task failure. Pre- and post-task measures included maximal voluntary isometric contractions (MVIC), and voluntary activation and contractile properties of the plantar flexor muscles, assessed using peripheral electrical stimulation of the tibial nerve. Surface electromyography was recorded for the medial and lateral gastrocnemius, soleus, and anterior tibialis muscles., Results: The SLHR resulted in 20.5% reductions in MVIC torque (p<0.001). However, the number of SLHR repetitions was not correlated with either the baseline MVIC (maximal strength; p = 0.979) or the reduction in MVIC following the SLHR (p = 0.23). There were no sex differences in either the number of SLHR repetitions (p = 0.14), baseline MVIC torque (p = 0.198), or the reduction of MVIC (p = 0.14). MVIC decline was positively associated with the reduction in voluntary activation (r = 0.841, p<0.001), but was not associated with the change in twitch amplitude (p = 0.597)., Conclusions: The SLHR was similar in young males and females yet was a poor predictor of maximal plantar flexor strength but evaluates performance fatigability of the lower extremity specific to dynamic contractions. The reduction in maximal strength at task failure was explained by reduced neural drive to the plantar flexor muscles in both males and females., Impact Statement: SLHR performance is not a clinical assessment of plantar flexor strength but assesses dynamic lower extremity fatigability that is similar in males and females. Alternate clinical measures for maximal plantar flexion strength need to be developed., Competing Interests: The authors have declared that no competing interests exist.

Aging is associated with large between-subjects variability in motor function among older adults, which can compromise identifying the mechanisms for age-related reductions in motor performance. This variability is in part explained by differences among older adults in habitual physical activity. Quantifying and accounting for physical activity levels of the participants in aging studies will help differentiate those changes in motor function associated with biological aging rather than those induced by inactivity. Novelty: Quantification of physical activity levels in studies with older participants will help differentiate the effects of aging rather than physical inactivity.

Black Americans have increased risk for schizophrenia and other mental illnesses with prenatal origins. Prenatal choline promotes infant brain development and behavioral outcomes, but choline has not been specifically assessed in Black Americans. Pregnant women (N = 183, N = 25 Black Americans) enrolled in a study of prenatal stressors and interactions with prenatal choline. Black American women had lower 16-week gestation plasma choline than Whites. Lower choline was not related to obesity, income, or metabolic genotypes. Pregnant women in rural Uganda have higher choline levels than Black American women. Black Americans' lower choline was associated with higher hair cortisol, indicative of higher stress. Lower maternal choline was associated with offsprings' lower gestational age at birth and with decreased auditory P50 inhibition, a marker of inhibitory neuron development. Behavioral development was assessed on the Infant Behavior Questionnaire-R-SF (IBQ-R) at 3 months. Lower Black American maternal gestational choline was associated with lower infant IBQ-R Orienting/Regulation, indicating decreased attention and relation to caregivers. Additional evidence for developmental effects of choline in Black Americans comes from a randomized clinical trial of gestational phosphatidylcholine supplementation versus placebo that included 15 Black Americans. Phosphatidylcholine increased gestational age at birth and newborn P50 inhibition and decreased Social Withdrawn and Attention problems at 40 months of age in Black Americans' offspring compared to placebo. Inhibitory and behavioral deficits associated with lower prenatal choline in offspring of Black American women indicate potential developmental predispositions to later mental illnesses that might be ameliorated by prenatal choline or phosphatidylcholine supplementation., (© The Author(s) 2020. Published by Oxford University Press on behalf of the Maryland Psychiatric Research Center.All rights reserved. For permissions, please email: journals.permissions@oup.com.)

These initial data suggest that with prenatal vitamins and choline supplements, we might decrease one risk factor associated with poorer health outcomes disproportionally affecting Black families, ie, preterm birth. Dissemination of this research fulfills the principle of Justice in the Belmont Report, to ensure that participants from different racial, ethnic and socioeconomic groups receive benefits from research directed to their specific problems., (© The Author(s) 2021. Published by Oxford University Press on behalf of the Maryland Psychiatric Research Center. All rights reserved. For permissions, please email: journals.permissions@oup.com.)

Background & Aims: Maternal gestational infection is a well-characterized risk factor for offsprings' development of mental disorders including schizophrenia, autism, and attention deficit disorder. The inflammatory response elicited by the infection is partly directed against the placenta and fetus and is the putative pathogenic mechanism for fetal brain developmental abnormalities. Fetal brain abnormalities are generally irreversible after birth and increase risk for later mental disorders. Maternal immune activation in animals models this pathophysiology. SARS-CoV-2 produces maternal inflammatory responses during pregnancy similar to previously studied common respiratory viruses., Method: Choline, folic acid, Vitamin D, and n-3 polyunsaturated fatty acids are among the nutrients that have been studied as possible mitigating factors for effects of maternal infection and inflammation on fetal development. Clinical and animal studies relevant to their use in pregnant women who have been infected are reviewed., Results: Higher maternal choline levels have positive effects on the development of brain function for infants of mothers who experienced viral infections in early pregnancy. No other nutrient has been studied in the context of viral inflammation. Vitamin D reduces pro-inflammatory cytokines in some, but not all, studies. Active folic acid metabolites decrease anti-inflammatory cytokines. N-3 polyunsaturated fatty acids have no effect., Conclusions: Vitamin D and folic acid are already supplemented in food additives and in prenatal vitamins. Despite recommendations by several public health agencies and medical societies, choline intake is often inadequate in early gestation when the brain is forming. A public health initiative for choline supplements during the pandemic could be helpful for women planning or already pregnant who also become exposed or infected with SARS-CoV-2., Competing Interests: Declaration of competing interest The authors declare that they have no competing interests., (Copyright © 2021 European Society for Clinical Nutrition and Metabolism. Published by Elsevier Ltd. All rights reserved.)

There is scientific and legal controversy about recent technological advances in performance running shoes that reduce the energetic cost of running and may provide a distinct competitive advantage. To better understand the potential performance-enhancing effects of technological advancements in marathon racing shoes, we examined the finishing times and racing shoes of the top 50 male and 50 female runners from the World Marathon Major series in the 2010s before and after the introduction of new Nike shoe models (4%, NEXT%, Alphafly, and other prototypes; herein referred to as "neoteric Nikes"). Data for racing shoes were available for 3,886 of the 3,900 performances recorded at the four annual marathons in Boston, London, Chicago, and New York. In full cohort analyses, marathon finishing times were 2.0% or 2.8 min (138.5 ± 8.1 min vs. 141.3 ± 7.4 min, P < 0.001) faster for male runners wearing neoteric Nikes compared with other shoes. For females, marathon finishing times were 2.6% or 4.3 min (159.1 ± 10.0 min vs. 163.4 ± 10.7 min, P < 0.001) faster for runners wearing neoteric Nikes. In a subset of within-runner changes in marathon performances (males, n = 138; females, n = 101), marathon finishing times improved by 0.8% or 1.2 min for males wearing neoteric Nikes relative to the most recent marathon in which other shoes were worn, and this performance-enhancing effect was greater among females who demonstrated 1.6% or 3.7 min improvement ( P = 0.002). Our results demonstrate that marathon performances are substantially faster when world-class athletes, and particularly females, wear marathon racing shoes with technological advancements. NEW & NOTEWORTHY World-class athletes are substantively faster, wearing marathon racing shoes with technological advancements than other shoes when competing in the marathon. Our findings suggest that technological advances in footwear contributed to the recent improvements in marathon finishing times among elite runners and in record-setting marathon performances. This investigation highlights the importance of sports analytics and may have broad implications for the regulation of running footwear during competition.

Purpose: The aim of this study was to determine the local and systemic effects of isometric and concentric muscle contractions on experimental pain and performance fatigability in people with and without fibromyalgia., Methods: Forty-seven fibromyalgia (FM: 51.3 ± 12.3 year) and 47 control (CON: 52.5 ± 14.7 year) participants performed submaximal isometric and concentric exercise for 10 min with the right elbow flexors. Assessments before and after exercise included pressure pain thresholds (PPT) of the biceps and quadriceps, central pain summation, self-reported exercising arm and whole-body pain, and maximal voluntary isometric contraction (MVIC) of the right elbow flexors and left handgrip., Results: People with FM experienced greater reductions in local fatigue (right elbow flexor MVIC: CON: - 4.0 ± 6.7%, FM: - 9.8 ± 13.8%; p = 0.013) and similar reductions in systemic fatigue (left handgrip MVIC: - 6.5 ± 10.2%; p < 0.001) as CON participants, which were not different by contraction type nor related to baseline clinical pain, perceived fatigue, or reported pain with exercise. Following exercise both groups reported an increase in PPTs at the biceps (pre: 205.5 ± 100.3 kPa, post: 219.0 ± 109.3 kPa, p = 0.004) only and a decrease in central pain summation (pre: 6.8 ± 2.9, post: 6.5 ± 2.9; p = 0.013). FM reported greater exercising arm pain following exercise (CON: 0.7 ± 1.3, FM: 2.9 ± 2.3; p < 0.001), and both groups reported greater arm pain following concentric (isometric: 1.4 ± 2.0, concentric: 2.2 ± 2.9; p = 0.001) than isometric exercise. Neither group reported an increase in whole-body pain following exercise., Conclusion: People with FM experienced greater performance fatigability in the exercising muscle compared to CON that was not related to central mechanisms of fatigue or pain. These results suggest changes in performance fatigability in FM may be due to differences occurring at the muscular level. TRIAL REGISTRATION #: NCT #: NCT03778385, December 19, 2018, retrospectively registered. IRB#: HR-3035.