Search

Abstract Objective Participants Methods Results Conclusions To examine the effects of a mindfulness intervention on health-related quality of life in female Division I collegiate athletes.135 female collegiate athletes, ages 18 – 23 yearsHealth related quality of life (HRQoL) was reported twice/year in approximately January and July from January 2017 to 2020 with the 12-question Veterans Rand survey (VR-12). Twenty-three of the participants received a 6-week, in-person, group mindfulness training in spring 2019, while 112 did not.A significant interaction between time and mindfulness was identified with respect to the mental component score of the VR-12 of the VR-12 (MCS; β = 3.86 ± 1 .56, p = 0.012) but no significant relationships were identified with respect to time (pre-mindfulness: β = −2.36 ± 1.38, p = 0.074), mindfulness (yes: β = −2.26 ± 1.54, p = 0.14) or season (winter: β = −0.84 ± 0.57, p = 0.14). With respect to the physical component score (PCS), no significant relationships were identified with respect to time (pre-mindfulness: β = −1.09 ± 1.21, p = 0.37), mindfulness (yes: β = 1.30 ± 1.31, p = 0.32), season (winter: β = 0.50 ± 0.50, p = 0.32), or the interaction between time and mindfulness (β = 0.35 ± 1 .36, p = 0.80).Among female collegiate athletes, mindfulness training is associated with significant improvements in mental HRQoL, but not physical HRQoL. [ABSTRACT FROM AUTHOR]

Background: Patients who undergo hip arthroscopy for femoroacetabular impingement (FAI) require lower extremity immobilization for an extended period of time. Periods of immobilization combined with surgery have been associated with decreased muscle mass and bone mineral density (BMD)., Purpose/hypothesis: The purpose of this study was to characterize postoperative body composition and BMD changes after arthroscopy for FAI. It was hypothesized that both lean mass and BMD would decrease postoperatively and then normalize over time., Study Design: Case series; Level of evidence, 4., Methods: This was a retrospective review of 23 National Collegiate Athletic Association Division I athletes who underwent hip arthroscopy between 2017 and 2019 and had a dual-energy x-ray absorptiometry scan preoperatively and at 3, 6, 12, or 24 months postoperatively. Linear mixed-effects models were used to compare pre- with postoperative lean and fat mass values for the total body and total leg (both operative and nonoperative sides) as well as trunk, pelvic, and spinal BMD. For total-leg, femur, and femoral BMD, linear mixed-effects models were used to evaluate the influence of time, side (operative vs nonoperative), and their interaction on each outcome measure., Results: Regarding pelvic BMD, compared with baseline (mean, 1.41 g/cm 2 [95% CI, 1.33-1.49]), significant decreases were seen at postoperative 3 months (mean, 1.36 g/cm 2 [95% CI, 1.28-1.45 g/cm 2 ]; P < .001) and 6 months (mean, 1.39 g/cm 2 [95% CI, 1.27-1.52 g/cm 2 ]; P < .01) but not at 12 months (mean, 1.42 g/cm 2 [95% CI, 1.33-1.51 g/cm 2 ]; P = .319). Total-leg BMD for the operative side increased significantly from baseline (mean, 1.52 g/cm 2 [95% CI, 1.43-1.61 g/cm 2 ]) to ≥2 years postoperatively (mean, 1.56 g/cm 2 [95% CI, 1.47-1.65 g/cm 2 ]) ( P = .005). Combined leg fat mass was increased from baseline (mean, 6427 g [95% CI, 4855-7999 g]) to ≥2 years (mean, 11645 g [95% CI, 7845-15,446 g]) ( P < .01). There were no significant differences in total-body fat or lean mass or combined-leg lean mass., Conclusion: In this patient population, a postoperative decrease in pelvic BMD that resolved by 12 months and an increase in total-leg BMD on the operative side at ≥2 years were observed. While hip arthroscopy for FAI may have significant benefits for long-term body composition and bone mass, clinicians should be aware of the potential implications of decreased bone mass for up to 12 months postoperatively., Competing Interests: One or more of the authors has declared the following potential conflict of interest or source of funding: B.E.W. has received hospitality payments from Smith+Nephew and Styker. AOSSM checks author disclosures against the Open Payments Database (OPD). AOSSM has not conducted an independent investigation on the OPD and disclaims any liability or responsibility relating thereto., (© The Author(s) 2024.)

Background: The use of bone-patellar tendon-bone (BPTB) and hamstring tendon (HT) autografts is common in anterior cruciate ligament reconstruction (ACLR). After ACLR, patients typically progress through specific rehabilitation milestones, and graft type may play a role in patient progression., Purpose: To compare the time to meet rehabilitation milestones between BPTB and HT autografts after ACLR., Design: Cohort study; Level of evidence, 3., Methods: This was a single-institution study on patients who underwent ACLR with either BPTB or HT autograft between June 2018 and July 2021. The primary outcomes were time to meet return-to-sport criteria, including >90% limb symmetry index (LSI) for isokinetic quadriceps and hamstring strength, horizontal hop, 4-crossover hop, and single-hop height. The time to satisfaction of each criterion was compared between graft groups using Wilcoxon tests and Cox proportional hazards models., Results: Included in the analysis were 410 participants who underwent ACLR with either BPTB (n = 232) or HT (n = 178). The BPTB group took longer to achieve >90% LSI for knee extension than HT (11.1 ± 4.1 vs 7.63 ± 2.8 months; P < .001). Similarly, the BPTB group took longer than the HT group to achieve >90% LSI for horizontal hop (11.4 ± 3.5 vs 9.82 ± 2.8 months; P < .001), 4-crossover hop (11.8 ± 3.6 vs 10.4 ± 2.8 months; P = .002), and single-hop height testing (11 ± 3.7 vs 8.81 ± 3.2 months; P < .001). The median time to achieve >90% LSI for hamstring strength was similar between groups (7.18 ± 3 vs 7.56 ± 3.1 months; P = .2)., Conclusion: Patients that underwent ACLR with BPTB autograft took longer than patients with HT to meet commonly used postoperative rehabilitation milestones. Clinicians should consider these differences when guiding patients regarding graft choice, postoperative expectations, and rehabilitation., Competing Interests: One or more of the authors has declared the following potential conflict of interest or source of funding: B.E.W. has received hospitality payments from Smith + Nephew and Stryker. AOSSM checks author disclosures against the Open Payments Database (OPD). AOSSM has not conducted an independent investigation on the OPD and disclaims any liability or responsibility relating thereto., (© The Author(s) 2024.)

Background: Self-reported wellbeing measures such as mood and soreness have been identified as predictors of injury risk. However, most research has focused on investigating time-loss injuries even though nontime-loss injuries are more prevalent., Hypothesis: Impairments in sleep and subjective wellbeing would be associated with increased injury for both time-loss and nontime-loss injuries., Study Design: Prospective longitudinal study., Level of Evidence: Level 3., Methods: During 2022, 127 athletes completed a daily survey that inquired about training load and sleep from the previous day along with mood, stress, and soreness on the current day. Incidence of injury was also monitored using documentation provided by athletes' respective athletic trainers. Mixed effect models were used to analyze the relationship between wellbeing and sleep measures with injury., Results: Self-reported wellbeing, based most closely on soreness the day of injury, by National Collegiate Athletic Association Division 1 collegiate athletes was predictive of time-loss injuries, whereas no significant relationship was identified for nontime-loss injuries. Specifically, 1 unit increase in soreness was associated with a 39% increase in odds of sustaining a time-loss injury., Conclusion: This study found that subjective wellbeing and sleep have a different relationship with injury dependent upon whether the resulting injury leads to time loss., Clinical Relevance: Self-reported wellbeing appears to be a relevant predictor of injury among collegiate athletes for time-loss injuries., Competing Interests: The authors report no potential conflicts of interest in the development and publication of this article.

Background: Injury in sport is an inherent risk to participation, and it can have devastating consequences for the athlete, both mentally and physically. Previous research has found that impairments in well-being can increase the risk of injury, and that various forms of mindfulness training and practice can improve well-being and mental health in various populations., Hypothesis: Mindfulness would be associated with greater well-being and lower risk of injury., Study Design: Cohort study., Level of Evidence: Level 3., Methods: A total of 21 female Division I athletes underwent a formal 6-week mindfulness training program and were encouraged to continue mindfulness exercises. The athletes completed daily surveys on their smartphones in relation to mood, muscle readiness (soreness), readiness to train, energy level, daily training load, and whether they had participated in mindfulness training that day. Linear mixed effects models were used to evaluate well-being variables and mindfulness state, and separate mixed effects logistics regression models were used to evaluate injury incidence and wellness variables., Results: On days with mindfulness practice, athletes reported higher mood (19.6 [18.8-20.3] vs 19.4 [18.6-20.1, P = 0.03), muscle readiness (18.9 [17.8-20.0] vs 18.6 [17.5-19.6], P = 0.03), readiness to train (78.7 [75.9-81.5] vs 77.4 [74.7-80.2], P < 0.01), and energy level (19.3 [18.6-20.1] vs 18.8 [18.1-19.5, P < 0.01) than on the days when they did not participate in mindfulness training. Mindfulness practice was associated with significantly reduced likelihood of suffering an acute injury the following day (odds ratio, 0.42; 95% CI, 0.42-0.43; P < 0.01)., Conclusion: On an individual level, participation in mindfulness by female collegiate athletes was associated with a dramatic reduction in injury risk the following day. In addition, mindfulness was associated with significantly improved mood, muscle readiness, readiness to train, and energy level., Clinical Relevance: These findings suggest that mindfulness training in athletes may improve well-being and reduce the risk of injury among high-level athletes., Competing Interests: The authors report no potential conflicts of interest in the development and publication of this article.

Background: The purpose of this study was to compare the benefits of sport participation with no sport participation during the COVID-19 pandemic and determine the moderating effects of race and ethnicity, socioeconomic status (SES), and physical activity (PA) on mental health in adolescent athletes., Hypothesis: Sport participation would be associated with greater improvements in mental health for athletes from racial and ethnic minority and lower SES groups compared with White and high SES groups. PA would mediate <30% of the mental health benefits of sport participation., Study Design: Cross-sectional study., Level of Evidence: Level 4., Methods: In May 2021, adolescent athletes completed an online survey (demographics, sport participation, measures of anxiety and depression, PA). Participants were classified as those who played sports (PLY) and those who did not (DNP). Mental health symptoms for the PLY and DNP groups were compared via analysis of variance models that controlled for demographic variables. Moderating analyses assessed the interaction of sport participation status by (1) race and ethnicity (White/non-White) and (2) SES (high/low) with mental health. Mediation analyses assessed the degree that PA scores explained the differences in anxiety and depression between the 2 groups., Results: Participants included 4874 adolescent athletes (52% female; age, 16.1 ± 1.3 years; PLY, 91%). Athletes who returned to sport from racial minority groups and low SES had greater decreases in anxiety (race and ethnicity: interaction estimate (b) = -1.18 ± 0.6, P = 0.04; SES, b = -1.23 ± 0.5, P = 0.02), and depression (race and ethnicity: b = -1.19 ± 0.6, P = 0.05; SES, b = -1.21 ± 0.6, P = 0.03) compared with White and high SES athletes, respectively. PA explained 24% of anxiety ( P < 0.01) and 20% of depression scores ( P < 0.01)., Conclusion: Athletes who identify as a racial or ethnic minority and from areas of lower household income experienced disproportionately greater negative mental health impacts from sport restrictions during COVID-19., Clinical Relevance: Improving access to sports in traditionally underserved areas may have significant mental health impact for adolescents., Competing Interests: The authors report no potential conflict of interest in the development and publication of this article.

Background: The COVID-19 pandemic has had a significant effect on the mental health of athletes. How this has affected quality of life (QoL), specifically in the college population, is poorly defined., Hypothesis: During the COVID-19 pandemic, the mental and physical QoL will have decreased in collegiate athletes as compared with before the pandemic., Study Design: Cross-sectional study., Level of Evidence: Level 3., Methods: Division I athletes from a total of 23 varsity teams at a single institution completed surveys between 2018 and 2022. QoL was assessed using the Veterans RAND 12-Item Health Survey (VR-12). VR-12 scores were separated into mental component scores (MCS) and physical component scores (PCS). Separate linear mixed effects models evaluated changes in MCS and PCS from pre-COVID to during COVID overall, as well as differences in changes by sex and sport type (individual, team)., Results: For all athletes, the PCS increased (54.6 [95% CI 54.4-54.7] vs 55.1 [54.9-55.3]; P < 0.01) and the MCS decreased (55.2 [54.9-55.5] vs 53.5 [53.1-53.8]; P < 0.01) from pre-COVID to during COVID. When evaluating for sex, women demonstrated a greater increase in PCS (0.57 ± 0.22; P = 0.01) and greater decrease in MCS (1.06 ± 0.38; P < 0.01). With respect to sport type, individual sports demonstrated a greater decrease in MCS (1.46 ± 0.39; P < 0.01), but no interaction was identified for PCS (0.42 ± 0.23; P = 0.07)., Conclusion: Collegiate athletes demonstrated a decrease in their self-reported mental QoL during the COVID-19 pandemic, as compared with before the pandemic. This effect was most evident in women and in individual sports. Athletes also reported an increase in physical QoL during COVID that was also larger in women, but not related to sport., Clinical Relevance: This study demonstrates the impact of the COVID-19 pandemic on collegiate athletes' QoL, including negative effects on mental health. It also identifies cohorts of athletes (women, individual) who may be more significantly affected., Competing Interests: The following authors declared potential conflicts of interest: S.A. has received honoraria from Wisconsin Track Coach’s Association. D.W. has received consulting fees from Elite Clubs National League.

Context: Although the return to sports during COVID-19 has been associated with improvements in mental health and quality of life (QOL), whether these benefits are primarily due to increases in physical activity (PA) is unknown., Objective: To determine whether PA increases were responsible for the improvements in mental health and QOL among adolescents who returned to sport during the COVID-19 pandemic., Design: Cross-sectional study., Setting: Wisconsin secondary schools., Patients or Other Participants: A total of 559 adolescent athletes (age = 15.7 + 1.2 years, females = 43.6%) from 44 schools completed a survey in October 2020., Main Outcome Measure(s): Demographic information, whether they had returned to sport participation, school instruction type, anxiety (Generalized Anxiety Disorder-7), depression (Patient Health Questionnaire-9), QOL (Pediatric Quality of Life Inventory 4.0), and PA (Hospital for Special Surgery Pediatric Functional Activity Brief Scale). Mediation analysis was used to assess whether the relationships between sport status and anxiety, depression, and QOL were mediated by PA., Results: At the time of the study, 171 (31%) had returned to play and 388 (69%) had not. Athletes who had returned to play had less anxiety (3.6 ± 0.4 versus 8.2 ± 0.6, P < .001) and depression (4.2 ± 0.4 versus 7.3 ± 0.6, P < .001) and higher QOL (88.1 ± 1.0 versus 80.2 ± 1.4, P < .001) and more PA (24.0 ± 0.5 versus 16.3 ± 0.7, P < .001). Physical activity explained a significant, but small, proportion of the difference in depression (22.1%, P = .02) and QOL (16.0%, P = .048) but not anxiety (6.6%, P = .20) between athletes who had and those who had not returned to play., Conclusions: Increased PA was responsible for only a small portion of the improvements in depression and QOL among athletes who returned to sports. This suggests that most of the mental health benefits of sport participation for adolescents during the COVID-19 pandemic were independent of the benefits of increased PA., (© by the National Athletic Trainers’ Association, Inc.)

Purpose: To evaluate the changes in mental health, quality of life (QOL) and physical activity (PA) among adolescent athletes during the COVID-19 pandemic as organised sports resumed., Methods: Adolescent athletes completed surveys including demographic and sport participation information, 7-item Generalized Anxiety Disorder, 9-item Patient Health Questionnaire, Pediatric Quality of Life Inventory and the Hospital for Special Surgery Pediatric Functional Activity Brief Scale in May 2020 following COVID-19-related sport cancellations (Spring20) and after returning to sports in May 2021 (Spring21). The groups were balanced by inverse propensity score weighting and compared using analysis of variance models and ordinal regression models., Results: 17 421 participants were included (Spring20=13 002; Spring21=4419; 16.2±1.2 years; 53% female). Anxiety was significantly lower (better) in Spring21 (Spring20=7.0, 95% CI 6.9 to 7.1; Spring21=4.9, 95% CI 4.8 to 5.0, p<0.001), as was the prevalence of moderate to severe anxiety (Spring20=29.4%, Spring21=17.1%, p<0.001). Depression was significantly improved in Spring21 (Spring20=7.6, 95% CI 7.5 to 7.7; Spring21=4.6, 95% CI 4.5 to 4.8, p<0.001), as was the prevalence of moderate to severe depression (Spring20=32.2%, Spring21=15.4%, p<0.001). Athletes in Spring21 reported higher QOL (Spring20=79.6, 95% CI 79.3 to 79.9; Spring21=84.7, 95% CI 84.4 to 85.0, p<0.001) and increased levels of PA (Spring20=13.8, 95% CI 13.6 to 13.9; Spring21=22.7, 95% CI 22.6 to 22.9, p<0.001)., Conclusion: Early COVID-19 sports restrictions were associated with worsening mental health in adolescents. In 2021, after returning to sports, athletes reported significant improvements in mental health, QOL and PA, although mental health adversities remain an important priority., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2023. No commercial re-use. See rights and permissions. Published by BMJ.)

Context: High schools and youth sport organizations that restarted participation in the fall of 2020 during the COVID-19 pandemic relied on information sources to develop risk-mitigation procedures., Objective: To compare the risk-mitigation procedures and information sources used by high school athletic departments and youth sport organizations., Design: Cross-sectional study., Setting: Surveys of high school and youth sport organization programs from across the United States., Patients or Other Participants: A total of 1296 high schools and 584 youth sport organizations, representing 519 241 adolescent athletes, responded to the surveys., Main Outcome Measure(s): Surveys regarding restarting sport, COVID-19 cases, risk-reduction procedures, and the information sources used to develop risk-reduction plans in the fall of 2020 were distributed to high school athletic directors and youth sport directors throughout the United States. The proportions of high schools and youth sport organizations using different risk-reduction procedures and information sources were compared using the χ2 test., Results: High schools used more risk-reduction procedures than did youth sport organizations (high schools = 7.1 ± 2.1 versus youth sport organizations = 6.3 ± 2.4; P < .001) and were more likely than youth sport organizations to use symptom monitoring (high schools = 93% versus youth sport organizations = 85%, χ2 = 26.3; P < .001), temperature checks on site (66% versus 49%, χ2 = 53.4; P < .001), face masks for athletes during play (37% versus 23%, χ2 = 38.1; P < .001) and when off the field (81% versus 71%, χ2 = 26.1; P < .001), social distancing for staff (81% versus 68%, χ2 = 43.3; P < .001) and athletes off the field (83% versus 68%, χ2 = 57.6; P < .001), and increased facility disinfection (92% versus 70%, χ2 = 165.0; P < .001). Youth sport organizations relied more on information from sport national governing bodies than did high schools (youth sport organizations = 52% versus high schools = 10%, χ2 = 411.0; P < .001), whereas high schools were more likely to use information from sources such as the National Athletic Trainers' Association (high schools = 20% versus youth sport organizations = 6%, χ2 = 55.20; P < .001) and the National Federation of State High School Associations (high schools = 72% versus youth sport organizations = 15%, χ2 = 553.00; P < .001) for determining risk-reduction strategies., Conclusions: High schools and youth sport organizations reported using a broad range of risk-reduction procedures, but the average number was higher among high schools than youth sport organizations. Use of information from the Centers for Disease Control and Prevention and local health authorities was high overall, but use of information from professional health care organizations was low. Professional health care organizations should consider using additional measures to improve information uptake among stakeholders in youth sports., (© by the National Athletic Trainers' Association, Inc.)

Abstract: Haraldsdottir, K, Sanfilippo, J, Dawes, S, and Watson, A. Contribution of lean mass distribution on aerobic fitness and performance in NCAA division I female rowers. J Strength Cond Res 36(7): 1956-1960, 2022-The purpose of this study was to determine the relative influence of total lean body mass (LBM), body fat percentage (BF%), upper extremity lean mass (ULM), lower extremity lean mass (LLM), and trunk lean mass (TLM) on maximal aerobic capacity (V̇o2max) and time to exhaustion (Tmax) in female collegiate rowers. One hundred seven female collegiate rowers (aged 18-22 years) performed maximal progressive rowing ergometer testing to determine V̇o2max and Tmax. Body mass, LBM, BF%, ULM, LLM, and TLM were determined by using dual-energy x-ray absorptiometry. Separate multivariable linear regression models were performed to predict V̇o2max and Tmax by using LBM and BF% as predictors. In addition, separate linear regression models were used to predict V̇o2max and Tmax with ULM, LLM, and TLM as covariates. Subjects were aged 20 ± 3 years. V̇o2max was significantly predicted by LBM (r2 = 0.29, p < 0.001), but not BF% (r2 = 0.002, p = 0.79). Similarly, Tmax was significantly predicted by LBM (r2 = 0.25, p < 0.001), but not BF% (r2 = 0.003, p = 0.19). V̇o2max was significantly predicted by LLM (r2 = 0.12, p < 0.01), but not ULM (r2 = 0.08, p = 0.68) or TLM (r2 = 0.09, p = 0.17), and Tmax was significantly predicted by TLM (r2 = 0.09, p = 0.02), but not ULM (r2 = 0.07, p = 0.89) or LLM (r2 = 0.08, p = 32). Among female collegiate rowers, whole body LBM is a significant predictor of both V̇o2max and Tmax. However, LLM is a stronger predictor of V̇o2max while TLM is a stronger predictor Tmax, although each of these relationships has a low coefficient of determination. These findings suggest that aerobic fitness and performance may be influenced by regions of lean mass differently., (Copyright © 2022 National Strength and Conditioning Association.)

Objective: To evaluate the association between COVID-19 incidence among high-school athletes participating in different indoor winter sports and attending schools with in-person versus virtual instructional delivery., Design: Cross-sectional survey., Setting: US high schools., Participants: High-school athletic directors., Independent Variables: Indoor winter sports, school instructional delivery method, and state COVID-19 incidence., Main Outcome Measures: Surveys were distributed to high-school athletic directors throughout the United States regarding sport reinitiation and COVID-19 cases in winter 2020 to 2021. Separate mixed effects Poisson regression models were developed to evaluate the associations between reported COVID-19 incidence and (1) different sports and (2) school instructional delivery method, while adjusting for the background, state COVID-19 incidence., Results: Four hundred thirty schools had restarted fall sports, representing 31 274 athletes on 1404 teams from 14 states. One thousand four hundred sixty cases of COVID-19 were reported, representing a case rate of 4668 cases per 100 000 athletes and an incidence rate of 58.7 cases per 100 000 player-days. Reported COVID-19 incidence was greatest among girls' hockey (82.1 cases per 100 000 player-days (95% CI, 56.8-115) and boys' hockey [76.7 (61.8-94.2)] and lowest among swimming [39.0 (31.1-48.2)] and gymnastics [28.5 (13.1-54.2)]. No difference in reported COVID-19 incidence was identified among athletes attending schools with virtual versus in-person instruction [incidence rate ratio = 0.86 (0.52-1.4)]., Conclusions: In this nationwide survey of US high-school athletic directors regarding indoor winter sports, reported COVID-19 incidence was lower in noncontact sports but unrelated to school instructional delivery method. This information may help guide decision-making regarding high-school sport participation during the COVID-19 pandemic., Competing Interests: T. McGuine serves on the Sports Medicine Advisory Council of the National Federation of State High School Associations. The remaining authors report no conflicts of interest., (Copyright © 2021 Wolters Kluwer Health, Inc. All rights reserved.)

Objective: To describe the incidence of COVID-19 in Wisconsin high school athletes and investigate the relationship of COVID-19 incidence with sport and face mask use., Design: Retrospective survey., Setting: High schools across Wisconsin during September 2020., Patients or Other Participants: Athletic directors representing 30 074 high school athletes with or without SARS-CoV-2., Main Outcome Measurement(s): The COVID-19 rates among athletes, counties, states, as well as school instruction type (virtual versus in person), sport type, and face mask use were assessed. Reported athlete case rates were compared with the county's general population and associations between COVID-19 incidence and sport type and face mask use, adjusting for each school's county incidence using multivariable negative binomial regression models., Results: The COVID-19 incidence rates for 207 of 244 responding schools were 32.6 cases per 100 000 player-days. Reported case rates for athletes in each county were positively correlated with the county's general population case rates (β = 1.14 ± 0.20, r = 0.60, P < .001). One case (0.5%) was attributed to sport contact by the reporting schools. No difference was identified between team and individual sports (incidence rate ratio [IRR] = 1.03 [95% CI = 0.49, 2.2], P = .93) or between noncontact and contact sports (IRR = 0.53 [0.23, 1.3], P = .14). Outdoor sports had a lower incidence rate than indoor sports, although this finding did not reach statistical significance (IRR = 0.52 [0.26, 1.1], P = .07). No significant associations were found between COVID-19 incidence and face mask use during play for those sports with greater than 50 schools reporting on face mask use (P values > .05)., Conclusions: The incidence of reported COVID-19 among high school athletes was related to the county incidence, and most cases were attributed to nonsport contact. A lower COVID-19 incidence in outdoor sports approached statistical significance. The lack of a significant benefit demonstrated for face mask use may be due to relatively low rates of COVID-19 in Wisconsin during September 2020. Further research is needed to better define COVID-19 transmission risk factors during adolescent sport participation., (© by the National Athletic Trainers' Association, Inc.)

Abstract: Interventions to promote athlete health and performance have traditionally been focused on the physical elements of injury and training. More recently, however, increasing attention has been placed on the mental aspects of athlete health, with emerging evidence suggesting that injury risk and athletic performance are significantly affected by athlete well-being. Mindfulness meditation has been shown to have significant benefits for a number of physical and mental health outcomes in various clinical populations, and recent research has explored how mindfulness may enhance athletic performance, improve athlete mental health, reduce injury risk, and perhaps even facilitate recovery from injury. As awareness of mindfulness as a noninvasive, low-risk, and accessible intervention increases in the Western society, use among athletes has increased as well. Health care providers should be aware of this evidence in order to guide athletes regarding the use of mindfulness as an intervention to potentially improve athlete health and performance., (Copyright © 2021 by the American College of Sports Medicine.)

Context: The relationships between different sports, face mask use and COVID-19 risk among high school athletes remains unknown., Objective: The purpose of this study was to evaluate the influence of sport characteristics and face mask use on COVID-19 incidence among high school athletes., Design: Descriptive Epidemiology Study Setting: United States High School Athletic Departments Participants: Athletic Directors Interventions: None Main Outcome Measures: Surveys were completed regarding sport re-initiation, COVID-19 cases, and risk reduction procedures in fall 2020. Separate mixed effects Poisson regression models were developed to evaluate the associations between reported COVID-19 incidence and 1) sport characteristics (contact/non-contact, individual/team, indoor/outdoor) and 2) face mask use while playing (yes/no)., Results: 991 schools had restarted fall sports, representing 152,484 athletes on 5,854 teams. 2,565 cases of COVID-19 were reported, representing a case rate of 1,682 cases per 100,000 athletes and an incidence rate of 24.6 cases per 100,000 player-days. COVID-19 incidence was lower among outdoor versus indoor sports (incidence rate ratio [IRR]=0.54, 95% CI=0.49-0.60, p<0.001) and non-contact versus contact sports (IRR=0.78 [0.70-0.87], p<0.001), but not team versus individual sports (IRR=0.96 [0.84-1.1], p=0.49). Face mask use was associated with a decreased incidence in girls' volleyball (IRR=0.53 [0.37-0.73], p<0.001), boys' basketball (IRR=0.53 [0.33-0.83], p=0.008) and girls' basketball (IRR=0.36 [0.19-0.63], p<0.001), and approached statistical significance in football (IRR=0.79 [0.59-1.04], p=0.10) and cheer/dance (IRR=0.75 [0.53-1.03], p=0.081)., Conclusions: In this nationwide survey of high school athletes, lower COVID-19 incidence was independently associated with participation in outdoor versus indoor and non-contact versus contact sports, but not team versus individual sports. Face mask use was associated with decreased COVID-19 incidence among indoor sports, and may be protective among outdoor sports with prolonged close contact between participants.

Background: Preterm birth has been linked to an elevated risk of heart failure and cardiopulmonary disease later in life. With improved neonatal care and survival, most infants born preterm are now reaching adulthood. In this study, we used 4D flow cardiovascular magnetic resonance (CMR) coupled with an exercise challenge to assess the impact of preterm birth on right heart flow dynamics in otherwise healthy adolescents and young adults who were born preterm., Methods: Eleven young adults and 17 adolescents born preterm (< 32 weeks of gestation and < 1500 g birth weight) were compared to 11 young adult and 18 adolescent age-matched controls born at term. Stroke volume, cardiac output, and flow in the main pulmonary artery were quantified with 4D flow CMR. Kinetic energy and vorticity were measured in the right ventricle. All parameters were measured at rest and during exercise at a power corresponding to 70% VO 2max for each subject. Multivariate linear regression was used to perform age-adjusted term-preterm comparisons., Results: With exercise, stroke volume increased 10 ± 21% in term controls and decreased 4 ± 18% in preterm born subjects (p = 0.007). This resulted in significantly reduced capacity to increase cardiac output in response to exercise stress for the preterm group (58 ± 26% increase in controls, 36 ± 27% increase in preterm, p = 0.004). Elevated kinetic energy (KE term  = 71 ± 22 nJ, KE preterm  = 87 ± 38 nJ, p = 0.03) and vorticity (ω term  = 79 ± 16 s -1 , ω preterm  = 94 ± 32 s -1 , p = 0.01) during diastole in the right ventricle (RV) suggested altered RV flow dynamics in the preterm subjects. Streamline visualizations showed altered structure to the diastolic filling vortices in those born preterm., Conclusions: For the participants examined here, preterm birth appeared to result in altered right-heart flow dynamics as early as adolescence, especially during diastole. Future studies should evaluate whether the altered dynamics identified here evolves into cardiopulmonary disease later in life. Trial registration None., (© 2021. The Author(s).)

Background: The relationship among sleep duration, subjective well-being, and injury risk in athletes is poorly defined., Purpose: To evaluate the independent effects of sleep duration, sleep quality, and subjective well-being on in-season injuries in collegiate female volleyball athletes., Study Design: Cohort study; Level of evidence, 2., Methods: During a 9-month competitive season, 17 female National Collegiate Athletic Association (NCAA) Division I volleyball players reported mood, fatigue, stress, soreness, sleep duration (hours), and sleep quality every morning. Well-being measures were recorded from 0 (worst) to 5 (best), and all time-loss injuries were recorded by the team athletic trainer. Separate mixed-effects logistic regression models were used to evaluate the effects of sleep and subjective well-being on in-season injury. Each well-being variable was also included in a separate mixed-effects logistic regression model with sleep duration as a covariate., Results: A total of 54 injuries were recorded during the study period. Compared with days without an injury, mood, fatigue, stress, soreness, sleep quality, and sleep duration were significantly worse the day before an injury occurred. In the separate prediction models, in-season injury was significantly predicted by fatigue (odds ratio [OR], 0.56 [95% CI, 0.36-0.86]; P = .008), mood (OR, 0.52 [95% CI, 0.35-0.78]; P = .002), stress (OR, 0.63 [95% CI, 0.42-0.94]; P = .023), soreness (OR, 0.54 [95% CI, 0.38-0.79]; P = .001), sleep quality (OR, 0.49 [95% CI, 0.34-0.7]; P < .001), and sleep duration (OR, 0.69 [95% CI, 0.55-0.87]; P = .001). In the multivariable models, sleep duration remained a significant independent predictor in each of the subsequent multivariable models (OR, 0.72-0.74; P < .05 for all), as did mood (OR, 0.55 [95% CI, 0.36-0.83); P = .005) and soreness (OR, 0.57 [95% CI, 0.39-0.83]; P = .003), while fatigue (OR, 0.65 [95% CI, 0.42-1]; P = .054) and stress (OR, 0.68 [95% CI, 0.45-1]; P = .061) no longer reached statistical significance., Conclusion: Increased sleep duration, mood, and decreased soreness were independently associated with a reduced risk of in-season injury in this cohort of female NCAA volleyball players., Competing Interests: The authors declared that there are no conflicts of interest in the authorship and publication of this contribution. AOSSM checks author disclosures against the Open Payments Database (OPD). AOSSM has not conducted an independent investigation on the OPD and disclaims any liability or responsibility relating thereto., (© The Author(s) 2021.)

Background: Premature birth is associated with lower levels of cardiorespiratory fitness (CRF) but the underlying mechanisms responsible remain unclear. This study assessed whether differences in cardiac morphology or function mediate differences in CRF among adolescents and young adults born preterm., Methods: Adolescents and young adults born moderately to extremely premature (gestational age ≤ 32 weeks or birth weight < 1500 g) and age-matched term born participants underwent resting cardiac MRI and maximal exercise testing. Mediation analysis assessed whether individual cardiovascular variables accounted for a significant proportion of the difference in maximal aerobic capacity between groups., Results: Individuals born preterm had lower VO2max than those born term (41.7 ± 8.6 v 47.5 ± 8.7, p < 0.01). Several variables differed between term and preterm born subjects, including systolic and diastolic blood pressure, mean pulmonary artery pressure, indexed left ventricular end-diastolic volume (LVEDVi), right ventricular end-diastolic volume (RVEDVi), LV mass (LVMi), LV stroke volume index (LVSVi), and LV strain (p < 0.05 for all). Of these variables, LVEDVi, RVEDVi, LVSVi, LVMi, and LV longitudinal strain were significantly related to VO2max (p < 0.05 for all). Significant portions of the difference in VO2max between term and preterm born subjects were mediated by LVEDVi (74.3%, p = 0.010), RVEDVi (50.6%, p = 0.016), and LVMi (43.0%, p = 0.036)., Conclusions: Lower levels of CRF in adolescents and young adults born preterm are mediated by differences in LVEDVi, RVEDVi, and LVMi. This may represent greater risk for long-term cardiac morbidity and mortality in preterm born individuals., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Objectives: The psychological impacts of injuries in youth athletes remain poorly defined. The purpose of this study was to evaluate the influence of injury on quality of life (QOL) and sleep in female high school volleyball athletes., Methods: 2073 female high school volleyball players (15.6±1.1 years) completed the Pediatric Quality of Life survey (total QOL, physical, social, school, emotional and psychosocial function) and reported average sleep duration at the start and end of the season. Injury data were collected by school athletic trainers. Mixed effects linear regression models were used to compare changes in QOL and sleep duration during the season between (1) injured and uninjured athletes and (2) injured athletes who did or did not suffer a season-ending injury., Results: Time-loss injuries were reported in 187 athletes with complete preseason and postseason data. During the season, injured athletes demonstrated a greater decrease in total QOL (β=-1.3±0.5, p=0.012), as well as physical function (β=-1.6±0.6, p=0.012), school function (β=-2.0±0.76, p=0.01) and psychosocial function domains (β=-1.2±0.6, p=0.039) compared with uninjured athletes. Athletes who sustained a season-ending injury had a significantly greater decrease in total QOL (β=-6.8±2.0, p=0.006) and physical function (β=-17±2.9, p<0.001) compared with injured athletes who were able to return to play during the season., Conclusion: In-season injuries are associated with significant decreases in total QOL as well as physical and psychosocial function. Healthcare providers should consider the impacts of injuries on QOL and sleep in youth athletes in order to optimise management and improve overall health., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2021. No commercial re-use. See rights and permissions. Published by BMJ.)

Context: As sports are reinitiated around the United States, the incidence of COVID-19 among youth soccer athletes remains unknown., Objective: To determine the incidence of COVID-19 among youth soccer athletes and the risk-mitigation practices used by youth soccer organizations., Design: Cohort study., Setting: Survey distributed to Elite Clubs National League member clubs., Patients or Other Participants: Youth soccer club directors throughout the United States., Main Outcome Measure(s): Surveys were completed in late August 2020 regarding the club's current phase of return to soccer (individual only, group noncontact, group contact), date of reinitiation, number of players, cases of COVID-19, and risk-reduction procedures being implemented. Case and incidence rates were compared with national pediatric data and county data from the prior 10 weeks. A negative binomial regression model was developed to predict club COVID-19 cases using the local incidence rate and phase of return as covariates and the log of club player-days as an offset., Results: A total of 124 respondents had reinitiated soccer, representing 91 007 players with a median duration of 73 days (interquartile range = 53-83 days) since restarting. Of the 119 clubs that had progressed to group activities, 218 cases of COVID-19 were reported among 85 861 players. Youth soccer players had a lower case rate and incidence rate than children in the United States (254 versus 477 cases per 100 000; incidence rate ratio = 0.511, 95% CI = 0.40, 0.57; P < .001) and the general population in the counties where data were available (268 versus 864 cases per 100 000; incidence rate ratio = 0.202, 95% CI = 0.19, 0.21; P < .001). After adjusting for the local COVID-19 incidence, we found no relationship between the club COVID-19 incidence and the phase of return (noncontact: b = 0.35 ± 0.67, P = .61; contact: b = 0.18 ± 0.67, P = .79). Soccer clubs reported using a median of 8 (interquartile range = 6-10) risk-reduction procedures., Conclusions: The incidence of COVID-19 among youth soccer athletes was relatively low when compared with the background incidence among children in the United States during the summer of 2020. No relationship was identified between the club COVID-19 incidence and the phase of return to soccer., (© by the National Athletic Trainers' Association, Inc.)

Context: The COVID-19 pandemic has affected almost every aspect of life including youth sports. Little data exists on COVID-19 incidences and risk mitigation strategies in youth club sports., Objective: To determine the reported incidence of COVID-19 cases among youth club sport athletes and the information sources used to develop COVID-19 risk mitigation procedures., Design: Cross-sectional study., Setting: Online surveys., Patients: Soccer and volleyball youth club directors., Intervention: A survey was completed by directors of youth volleyball and soccer clubs across the country in October 2020. Surveys included self-reported date of re-initiation, number of players, player COVID-19 cases, sources of infection, COVID-19 mitigation strategies, and information sources for the development of COVID-19 mitigation strategies., Main Outcome Measures: Total number of cases reported, number of players, and days since club re-initiation were used to calculate an incidence rate of cases per 100,000 player-days. To compare reported incidence rates between soccer and volleyball, a negative binomial model was developed to predict player cases with sport and state incidence as covariates and log(player-days) as an offset. Estimates were exponentiated to yield a reported incidence rate ratio (IRR) with Wald confidence intervals., Results: A total of 205,136 athletes (soccer=165,580; volleyball=39,556) were represented by 437 clubs (soccer=159; volleyball=278). Club organizers reported 673 COVID-19 cases (soccer=322; volleyball=351), for a reported incidence rate of 2.8 cases per 100,000 player-days (soccer=1.7, volleyball=7.9). Volleyball had a significantly higher reported COVID-19 incidence rate compared to soccer (reported IRR = 3.06 [2.0-4.6], p<0.001). Out of 11 possible mitigation strategies, the median number of strategies used by all clubs was 7 with an interquartile range of 2., Conclusions: The incidence of self-reported cases of COVID-19 was lower in soccer clubs than volleyball clubs. Most clubs report using many COVID-19 mitigation strategies to reduce the risk of COVID-19.

Abstract: Adolescence represents a time of tremendous physical, social, and emotional growth, and sport participation can provide significant mental health benefits for young athletes. Injuries are unfortunately common in sports and represent a threat to the short- and long-term health of athletes. While injury management has typically revolved around the minimization of pain and the restoration of physical function, emerging evidence suggests that the psychological consequences of injury may be significant, potentially jeopardizing return to play, increasing subsequent reinjury risk, and even leading to the development of mental health disorders. The majority of this research has been conducted in adult athletes and less is known about outcomes in youth athletes following injury. This review examines what is known about the psychosocial impact of sports injuries in youth athletes to identify areas of future research and to aid clinicians in the management of this population., (Copyright © 2021 by the American College of Sports Medicine.)

Purpose: Premature birth is associated with lasting effects, including lower exercise capacity and pulmonary function, and is acknowledged as a risk factor for cardiovascular disease. The aim was to evaluate factors affecting exercise capacity in adolescents born preterm, including the cardiovascular and pulmonary responses to exercise, activity level and strength., Methods: 21 preterm-born and 20 term-born adolescents (age 12-14 years) underwent strength and maximal exercise testing with thoracic bioimpedance monitoring. Baseline variables were compared between groups and ANCOVA was used to compare heart rate, cardiac output (Q) and stroke volume (SV) during exercise between groups while adjusting for body surface area., Results: Preterm-borns had lower maximal aerobic capacity than term-borns (2.0 ± 0.5 vs. 2.5 ± 0.5 L/min, p = 0.01) and lower maximal power (124 ± 26 vs. 153 ± 33 watts, p < 0.01), despite similar physical activity scores. Pulmonary function and muscular strength did not differ significantly. Although baseline Q and SV did not differ between groups, preterm adolescents had significantly lower cardiac index (Qi) at 50, 75 and 100% of maximal time to exhaustion, driven by SV volume index (SVi, 50% max time: 53.0 ± 9.0 vs. 61.6 ± 11.4; 75%: 51.7 ± 8.4 vs. 64.3 ± 11.1; 100%: 51.2 ± 9.3 vs. 64.3 ± 11.5 ml/m 2 , all p < 0.01), with similar heart rates., Conclusion: Otherwise healthy and physically active adolescents born very preterm exhibit lower exercise capacity than term-born adolescents. Despite similar baseline cardiovascular values, preterm-born adolescents demonstrate significantly reduced Qi and SVi during incremental and maximal exercise.

Importance: Premature birth is associated with substantially higher lifetime risk for cardiovascular disease, including arrhythmia, ischemic disease, and heart failure, although the underlying mechanisms are poorly understood., Objective: To characterize cardiac structure and function in adolescents and young adults born preterm using cardiac magnetic resonance imaging (MRI)., Design, Setting, and Participants: This cross-sectional cohort study at an academic medical center included adolescents and young adults born moderately to extremely premature (20 in the adolescent cohort born from 2003 to 2004 and 38 in the young adult cohort born in the 1980s and 1990s) and 52 age-matched participants who were born at term and underwent cardiac MRI. The dates of analysis were February 2016 to October 2019., Exposures: Premature birth (gestational age ≤32 weeks) or birth weight less than 1500 g., Main Outcomes and Measures: Main study outcomes included MRI measures of biventricular volume, mass, and strain., Results: Of 40 adolescents (24 [60%] girls), the mean (SD) age of participants in the term and preterm groups was 13.3 (0.7) years and 13.0 (0.7) years, respectively. Of 70 adults (43 [61%] women), the mean (SD) age of participants in the term and preterm groups was 25.4 (2.9) years and 26.5 (3.5) years, respectively. Participants from both age cohorts who were born prematurely had statistically significantly smaller biventricular cardiac chamber size compared with participants in the term group: the mean (SD) left ventricular end-diastolic volume index was 72 (7) vs 80 (9) and 80 (10) vs 92 (15) mL/m2 for adolescents and adults in the preterm group compared with age-matched participants in the term group, respectively (P < .001), and the mean (SD) left ventricular end-systolic volume index was 30 (4) vs 34 (6) and 32 (7) vs 38 (8) mL/m2, respectively (P < .001). Stroke volume index was also reduced in adolescent vs adult participants in the preterm group vs age-matched participants in the term group, with a mean (SD) of 42 (7) vs 46 (7) and 48 (7) vs 54 (9) mL/m2, respectively (P < .001), although biventricular ejection fractions were preserved. Biventricular mass was statistically significantly lower in adolescents and adults born preterm: the mean (SD) left ventricular mass index was 39.6 (5.9) vs 44.4 (7.5) and 40.7 (7.3) vs 49.8 (14.0), respectively (P < .001). Cardiac strain analyses demonstrated a hypercontractile heart, primarily in the right ventricle, in adults born prematurely., Conclusions and Relevance: In this cross-sectional study, adolescents and young adults born prematurely had statistically significantly smaller biventricular cardiac chamber size and decreased cardiac mass. Although function was preserved in both age groups, these morphologic differences may be associated with elevated lifetime cardiovascular disease risk after premature birth.

First-trimester combined screening (FTS) has been offered to all pregnant women in Iceland since 2003. Individuals with high-risk FTS results are offered an invasive test option with a ≤1% risk of fetal loss. This study gives insight into the prenatal screening and diagnosis experiences and preferences of 101 women who underwent FTS in Iceland in the years 2012-2016, comparing the experience of those who received false-positive FTS results to those who received true-negative results. Retrospective patient-reported anxiety levels at the time of receiving FTS results were significantly higher in those who received false-positive results compared to those who received true-negative results. For a subset of these participants, the anxiety lasted through pregnancy, and for a smaller subset, it lasted even longer. Non-invasive prenatal testing (NIPT) is currently not offered in Iceland, aside from the rare exceptional case. Given the extremely low false-positive rates of NIPT, we believe NIPT is worth considering as Iceland's standard first-tier screening method for trisomy 13, 18, and 21. We believe the findings of this study are beneficial not only for Iceland but also for other countries where FTS is the first-tier prenatal screening method or the only offered test. Additionally, only 21% of participants in our study reported that they had heard of NIPT, which emphasizes the need for comprehensive NIPT pretest information to be available prior to its uptake to ensure informed and autonomous decision-making., (© 2020 National Society of Genetic Counselors.)

Purpose: The long-term implications of premature birth on autonomic nervous system (ANS) function are unclear. Heart rate recovery (HRR) following maximal exercise is a simple tool to evaluate ANS function and is a strong predictor of cardiovascular disease. Our objective was to determine whether HRR is impaired in young adults born preterm (PYA)., Methods: Individuals born between 1989 and 1991 were recruited from the Newborn Lung Project, a prospectively followed cohort of subjects born preterm weighing < 1500 g with an average gestational age of 28 weeks. Age-matched term-born controls were recruited from the local population. HRR was measured for 2 min following maximal exercise testing on an upright cycle ergometer in normoxia and hypoxia, and maximal aerobic capacity (VO 2max ) was measured., Results: Preterms had lower VO 2max than controls (34.88 ± 5.24 v 46.15 ± 10.21 ml/kg/min, respectively, p < 0.05), and exhibited slower HRR compared to controls after 1 and 2 min of recovery in normoxia (absolute drop of 20 ± 4 v 31 ± 10 and 41 ± 7 v 54 ± 11 beats per minute (bpm), respectively, p < 0.01) and hypoxia (19 ± 5 v 26 ± 8 and 39 ± 7 v 49 ± 13 bpm, respectively, p < 0.05). After adjusting for VO 2max , HRR remained slower in preterms at 1 and 2 min of recovery in normoxia (21 ± 2 v 30 ± 2 and 42 ± 3 v 52 ± 3 bpm, respectively, p < 0.05), but not hypoxia (19 ± 3 v 25 ± 2 and 40 ± 4 v 47 ± 3 bpm, respectively, p > 0.05)., Conclusions: Autonomic dysfunction as seen in this study has been associated with increased rates of cardiovascular disease in non-preterm populations, suggesting further study of the mechanisms of autonomic dysfunction after preterm birth.

Rationale: Premature birth affects 10% of live births in the United States and is associated with alveolar simplification and altered pulmonary microvascular development. However, little is known about the long-term impact prematurity has on the pulmonary vasculature. Objectives: Determine the long-term effects of prematurity on right ventricular and pulmonary vascular hemodynamics. Methods: Preterm subjects ( n  = 11) were recruited from the Newborn Lung Project, a prospectively followed cohort at the University of Wisconsin-Madison, born preterm with very low birth weight (≤1,500 g; average gestational age, 28 wk) between 1988 and 1991. Control subjects ( n  = 10) from the same birth years were recruited from the general population. All subjects had no known adult cardiopulmonary disease. Right heart catheterization was performed to assess right ventricular and pulmonary vascular hemodynamics at rest and during hypoxic and exercise stress. Measurements and Main Results: Preterm subjects had higher mean pulmonary arterial pressures (mPAPs), with 27% (3 of 11) meeting criteria for borderline pulmonary hypertension (mPAP, 19-24 mm Hg) and 18% (2 of 11) meeting criteria for overt pulmonary hypertension (mPAP ≥ 25 mm Hg). Pulmonary vascular resistance and elastance were higher at rest and during exercise, suggesting a stiffer vascular bed. Preterm subjects were significantly less able to augment cardiac index or right ventricular stroke work during exercise. Among neonatal characteristics, total ventilatory support days was the strongest predictor of adult pulmonary pressure. Conclusions: Young adults born preterm demonstrate early pulmonary vascular disease, characterized by elevated pulmonary pressures, a stiffer pulmonary vascular bed, and right ventricular dysfunction, consistent with an increased risk of developing pulmonary hypertension.

Mesenchymal stromal cell (MSC) derived exosomes mediate tissue protection and regeneration in many injuries and diseases by modulating cell protein production, protecting from apoptosis, inhibiting inflammation, and increasing angiogenesis. In the present study, daily intraperitoneal injection of MSC-derived exosomes protected alveolarization and angiogenesis in a newborn rat model of bronchopulmonary dysplasia (BPD) induced by 14 days of neonatal hyperoxia exposure (85% O 2 ). Exosome treatment during hyperoxia prevented disruption of alveolar growth, increased small blood vessel number, and inhibited right heart hypertrophy at P14, P21, and P56. In vitro, exosomes significantly increased tube-like network formation by HUVEC, in part through a VEGF mediated mechanism. In summary, daily intraperitoneal injection of exosomes increased blood vessel number and size in the lung through pro-angiogenic mechanisms. MSC-derived exosomes therefore have both anti-inflammatory and pro-angiogenic mechanism to protect the lung from hyperoxia induced lung and heart disease associated with BPD., (Published by Elsevier Inc.)

Purpose: To evaluate the influence of physical maturity on the changes in ventricular morphology and function with sport training in female youth athletes., Methods: Thirty-two female athletes (age 13-18 years) underwent height and weight measurement and 2-D echocardiographic evaluation immediately prior to, and following, a 20-week soccer season. Pre- and post-season left ventricular end-diastolic diameter (LVEDD), end-diastolic volume (LVEDV), ejection fraction (LVEF), stroke volume (LVSV), mass (LVM), and posterior wall thickness (LVPWT), right ventricular end-diastolic diameter (RVEDD), end-diastolic area (RVEDA), and fractional area change (RVFAC), and interventricular septal thickness (IVST) were compared. In-season change in each variable was compared across pre-season hours of vigorous physical activity (0-1, 2-3, >3 hours)., Results: Significant increases were identified in LVEDV (51.3 ± 10.4 v 56.4 ± 9.6 ml/m 2 , p = 0.001) and RVEDA (10.5 ± 1.9 v 11.3 ± 2.5 cm 2 /m 2 , p = 0.040), but not LVEDD, LVM, LVPWT, LVSV, RVEDD, RVEDA, RVFAC, or IVST (p > 0.05 for all). In-season changes in echocardiographic variables did not differ across hours of pre-season vigorous physical activity (p > 0.05 for all)., Conclusion: Among female adolescent soccer players, in-season training elicits changes in resting ventricular volume, but not wall thickness or systolic function. These adaptations do not appear to be influenced by pre-season physical activity level.

Premature birth affects more than 10% of live births, and is characterized by relative hyperoxia exposure in an immature host. Long-term consequences of preterm birth include decreased aerobic capacity, decreased muscular strength and endurance, and increased prevalence of metabolic diseases such as type 2 diabetes mellitus. Postnatal hyperoxia exposure in rodents is a well-established model of chronic lung disease of prematurity, and also recapitulates the pulmonary vascular, cardiovascular, and renal phenotype of premature birth. The objective of this study was to evaluate whether postnatal hyperoxia exposure in rats could recapitulate the skeletal and metabolic phenotype of premature birth, and to characterize the subcellular metabolic changes associated with postnatal hyperoxia exposure, with a secondary aim to evaluate sex differences in this model. Compared to control rats, male rats exposed to 14 days of postnatal hyperoxia then aged to 1 year demonstrated higher skeletal muscle fatigability, lower muscle mitochondrial oxidative capacity, more mitochondrial damage, and higher glycolytic enzyme expression. These differences were not present in female rats with the same postnatal hyperoxia exposure. This study demonstrates detrimental mitochondrial and muscular outcomes in the adult male rat exposed to postnatal hyperoxia. Given that young adults born premature also demonstrate skeletal muscle dysfunction, future studies are merited to determine whether this dysfunction as well as reduced aerobic capacity is due to reduced mitochondrial oxidative capacity and metabolic dysfunction.

Preterm birth temporarily disrupts autonomic nervous system (ANS) development, and the long-term impacts of disrupted fetal development are unclear in children. Abnormal cardiac ANS function is associated with worse health outcomes, and has been identified as a risk factor for cardiovascular disease. We used heart rate variability (HRV) in the time domain (standard deviation of RR intervals, SDRR; and root means squared of successive differences, RMSSD) and frequency domain (high frequency, HF; and low frequency, LF) at rest, as well as heart rate recovery (HRR) following maximal exercise, to assess autonomic function in adolescent children born preterm. Adolescents born preterm (less than 36 weeks gestation at birth) in 2003 and 2004 and healthy age-matched full-term controls participated. Wilcoxon Rank Sum tests were used to compare variables between control and preterm groups. Twenty-one adolescents born preterm and 20 term-born controls enrolled in the study. Preterm-born subjects had lower time-domain HRV, including SDRR (69.1 ± 33.8 vs. 110.1 ± 33.0 msec, respectively, P = 0.008) and RMSSD (58.8 ± 38.2 vs. 101.5 ± 36.2 msec, respectively, P = 0.012), with higher LF variability in preterm subjects. HRR after maximal exercise was slower in preterm-born subjects at 1 min (30 ± 12 vs. 39 ± 9 bpm, respectively, P = 0.013) and 2 min (52 ± 10 vs. 60 ± 10 bpm, respectively, P = 0.016). This study is the first report of autonomic dysfunction in adolescents born premature. Given prior association of impaired HRV with adult cardiovascular disease, additional investigations into the mechanisms of autonomic dysfunction in this population are warranted., (© 2018 The Authors. Physiological Reports published by Wiley Periodicals, Inc. on behalf of The Physiological Society and the American Physiological Society.)

Infants born premature are at increased risk for development of bronchopulmonary dysplasia (BPD), pulmonary hypertension (PH), and ultimately right ventricular (RV) dysfunction, which together carry a high risk of neonatal mortality. However, the role alveolar simplification and abnormal pulmonary microvascular development in BPD affects RV contractile properties is unknown. We used a rat model of BPD to examine the effect of hyperoxia-induced PH on RV contractile properties. We measured in vivo RV pressure as well as passive force, maximum Ca 2+ activated force, calcium sensitivity of force (pCa 50 ) and rate of force redevelopment ( k tr ) in RV skinned trabeculae isolated from hearts of 21-and 35-day old rats pre-exposed to 21% oxygen (normoxia) or 85% oxygen (hyperoxia) for 14 days after birth. Systolic and diastolic RV pressure were significantly higher at day 21 in hyperoxia exposed rats compared to normoxia control rats, but normalized by 35 days of age. Passive force, maximum Ca 2+ activated force, and calcium sensitivity of force were elevated and cross-bridge cycling kinetics depressed in 21-day old hyperoxic trabeculae, whereas no differences between normoxic and hyperoxic trabeculae were seen at 35 days. Myofibrillar protein analysis revealed that 21-day old hyperoxic trabeculae had increased levels of beta-myosin heavy chain (β-MHC), atrial myosin light chain 1 (aMLC1; often referred to as essential light chain), and slow skeletal troponin I (ssTnI) compared to age matched normoxic trabeculae. On the other hand, 35-day old normoxic and hyperoxic trabeculae expressed similar level of α- and β-MHC, ventricular MLC1 and predominantly cTnI. These results suggest that neonatal exposure to hyperoxia increases RV afterload and affect both the steady state and dynamic contractile properties of the RV, likely as a result of hyperoxia-induced expression of β-MHC, delayed transition of slow skeletal TnI to cardiac TnI, and expression of atrial MLC1. These hyperoxia-induced changes in contractile properties are reversible and accompany the resolution of PH with further developmental age, underscoring the importance of reducing RV afterload to allow for normalization of RV function in both animal models and humans with BPD.