Return to play and athletic performance in division I female volleyball players following anterior cruciate ligament injury

OBJECTIVES

The purpose of this study is to examine NCAA Division I volleyball players' return to play rates and performance statistics compared to pre-injury levels following ACL injury.

METHODS

Female volleyball players that sustained ACL injuries from 2008 to 2020 and competed in one of seven collegiate conferences (n = 99) were identified via an internet search algorithm. Players were categorized by position, academic year, and playing time pre- and post-injury. Post-injury performance statistics were gathered for a subset of outside hitters and middle blockers that played in ≥35 sets in a single season for up to 3 years following injury (mean 1.7 seasons). A control group (n = 512) was generated for demographic and statistical comparison. Mean pre-injury and post-injury statistics were compared for players that did not change positions and played ≥35 sets before and after injury.

RESULTS

Volleyball attackers were 54.7% of the control population but sustained 78.8% of identified injuries. Following ACL injury, 6.1% of players registered no in-game statistics, 16.2% played in <35 sets, 65.7% played in ≥35 sets, and 12.1% graduated. Mean performance statistics increased linearly the more years players were from ACL injury.

CONCLUSIONS

Female collegiate volleyball players return to play following ACL injury at high rates (93.1%) and maintain pre-injury performance levels. Volleyball attackers sustain ACL injuries more commonly than setters and libero/defensive specialists.

Preseason lower extremity range of motion, flexibility, and strength in relation to in-season injuries in NCAA division I gymnasts

OBJECTIVES

To determine if preseason lower extremity ROM, flexibility, and strength differ in collegiate gymnasts (NCAA Division 1) who do or do not sustain an injury during the competitive season.

METHODS

Over four seasons, a total of 15 female gymnasts (age = 20.5 ± 1.0 years) underwent preseason screening (30 gymnast-season). We tested joint ROM (hip: flexion, internal and external rotation; ankle: weightbearing dorsiflexion), muscle flexibility (passive straight leg raise, Thomas,' Ober's, Ely's tests) and strength (hip extensors, abductors, and flexors isometric strength via a handheld dynamometer; knee: quadriceps and hamstring isokinetic strength at 60°/sec). The team athletic trainer tracked overuse lower extremity injuries (restricted gymnasts from full participation, occurred as from participation in organized practice or competition, and required medical attention) during each season. For athletes that tested multiple seasons, each encounter was considered independent, and each preseason assessment was linked to overuse injuries sustained during the same competitive season. Gymnasts were dichotomized into injured and non-injured groups. An independent t-test was used to measure differences in preseason outcomes between injured and non-injured groups.

RESULTS

During four years, we recorded 23 overuse lower extremity injuries. Gymnasts that sustained an in-season overuse injury demonstrated significantly lower hip flexion ROM (mean difference: -10.6°; 95% confidence interval: -16.5, -4.6; p < 0.01) and lower hip abduction strength (mean difference: -4.7% of body weight; 95% confidence interval: -9.2, -0.3; p = 0.04).

CONCLUSION

Gymnasts who sustain an in-season overuse lower extremity injury have significant preseason deficit of hip flexion ROM and weakness in the hip abductors. These findings indicate potential impairments in the kinematic & kinetic chains responsible for skill performance and energy absorption during landing.

Effects of In-Exercise Carbohydrate Supplementation on Prolonged High-Intensity Exercise Performance in Oral Contraceptive Users

PURPOSE

To examine the impact of oral contraceptive (OC) phases on performance, physiological, and subjective responses to prolonged, intensive exercise when carbohydrate (CHO) stores are reduced.

METHODS

Ten well-trained female cyclists using monophasic OC completed 4 identical trials (>150 min) under conditions of in-trial 60-g·h-1 CHO supplementation (CHO+) or placebo (CHO-) during the sugar- (SUG) and active-pill (ACT) phases of their OC cycle. Each trial comprised two 400-kcal time trials (TT) separated by 1 hour of submaximal cycling at first ventilatory threshold.

RESULTS

Change in completion time from TT1 to TT2 was minimized in CHO+ compared with CHO- (4.06 [2.55] vs 6.08 [5.33] min; P = .019, effect size = -0.36). An interaction effect of OC and CHO was observed for time to complete TT (P = .006), mean TT power (P = .002), mean TT heart rate (P = .002), and posttrial emotional balance (P = .020) and negative emotional state (P = .033). In ACT, mean TT power and heart rate were higher in CHO+ when compared with CHO-, resulting in faster TTs in CHO+ and improved posttrial emotional well-being. When CHO was not supplemented, TT power and heart rate were higher in SUG when compared with ACT, resulting in faster TTs in SUG and improved posttrial emotional balance.

CONCLUSION

CHO depletion during ACT negatively influenced TT performance and emotional well-being when compared with SUG. Irrespective of OC pill phase, CHO supplementation should be prioritized to sustain performance and improve postexercise recovery-stress balance.

The developmental activities of women's professional pathway cricketers

The growth of investment in women's cricket has led to the development of new professional pathways. However, there is lack of specific evidence to support the development of these athletes. This study aimed to take a first step in understanding the participation histories of female cricketers selected into English women's professional academies. 84 players completed the Participation History Questionnaire (PHQ) to capture details of activities engaged in across development, including milestones, cricket activity, and engagement in other sport activities. There were relative age effects where players' birthdate distributions differed from national norms (X2 = 8.451, p = .003, V = 0.227), and more players than expected attended independent schools (X2 = 7.980, p = .005, V = 0.232). Participants engaged in cricket informally before coach led training, have siblings (particularly brothers) interested in cricket and often played boy's cricket before engaging in the girl's or women's game. Developmental activities were characterised by early engagement, high levels of diversification, and very low levels of play compared to high levels of formal practice and match play. These findings have implications for the advancement of talent identification and development policies and processes in women's cricket.

Changes in Sleep, Stress, and Fatigue Were Not Prospectively Associated With Running-Related Injuries Among High School Cross Country Runners

BACKGROUND

Running-related injuries (RRI) are common among adolescent runners; however, our understanding of RRI risk factors in this population is limited. Sleep, stress, and fatigue are risk factors in other youth sports but have not been studied in high school runners. This study prospectively assessed the effect of changes in sleep duration and quality, stress, and fatigue on RRI among high school cross country runners.

HYPOTHESIS

Less and poorer quality sleep and greater stress and fatigue, compared with the previous week, would be associated with RRI.

STUDY DESIGN

Prospective, observational study.

LEVEL OF EVIDENCE

Level 2b.

METHODS

Runners completed a preseason demographics and injury history survey and daily surveys regarding sleep duration and quality, stress, fatigue, and current RRI. Values were summed within each week, and change scores were calculated relative to the previous week. Runners completing ≥75% of daily surveys were analyzed; sensitivity analyses for those completing ≥50% and ≥90% were also conducted. Generalized estimating equations assessed the association between change in each predictor, including its interaction with sex, and RRI, controlling for year in school, previous RRI, and repeated observations.

RESULTS

A total of 434 runners enrolled in the study; 161 (37%) completed ≥75% of daily surveys. No associations between change in sleep duration, sleep quality, or fatigue and RRI were observed (P values ≥0.24). A significant change in stress × sex interaction with RRI was observed (P < 0.01). Associations among boys (P = 0.06) and girls (P = 0.07) were marginally significant. Sensitivity results were similar.

CONCLUSION

Short-term changes in sleep duration, quality, and fatigue were not associated with RRI, but a significant interaction between change in stress and sex suggests that stress may influence RRI risk in high school cross country runners.

CLINICAL RELEVANCE

Large changes in stress levels should be monitored throughout the season, as these changes may precede RRI occurrence in this population.

Body morphology and handgrip strength parameters of the female canoe slalom paddlers

Introduction: Canoe slalom is a physically very demanding discipline, in which body constitution, body composition, and relative strength are significant factors in high performance. Although anthropometric and strength parameters are relatively well-studied in male athletes, there is a lack of evidence for any conclusions in women. Therefore, the objective of this study was to determine the morphology and upper-limb strength parameters of female canoe slalom paddlers and identify whether morphological differences exist between performance groups. Methods: Altogether, 63 female competitors of the 2023 ICF Canoe Slalom World Cup (n = 29) and 2023 ICF Canoe Slalom World Ranking Competition (n = 34) in Prague (Czech Republic) were examined with a battery of anthropometric tests, segmental bioimpedance analysis, and handgrip strength test. The athletes were divided into groups according to age and performance: elite athletes belonging to the world top 10 according to the ICF World Ranking (WORLD, n = 7), international-level athletes competing during the World Cup (ELITE, n = 22), international-level junior athletes competing in the World Ranking Race (JUNIOR, n = 17), and other lower performance-level athletes competing in the World Ranking Race (REST, n = 17). Results: Female slalom paddlers are, in general, of average body height (∼165 cm), lower body mass (∼60 kg), BMI (∼22 kg/m2), and body fat (∼20%) and without exceptional anthropometric dimensions and proportions. However, differences were detected when performance was factored in. Female paddlers belonging to the world TOP 10 have the largest circumferences of arms and forearms, and their somatotype is more mesomorphic, with a lower proportion of total body fat and a higher proportion of muscle mass. In addition, the WORLD group differs significantly in upper-limb strength. Discussion: The results shows the significance of muscular strength and power for canoe slalom athletes and the importance of well-developed musculature in operating the boat in the unstable environment. Being a successful female canoe slalom athlete requires a well-developed musculature, maximizing strength capabilities while maintaining a low body weight through limited hypertrophy of the lower limbs and a low level of body fat.

Rib stress fracture in a female athlete caused by bouncing the barbell in bench press exercise: A case report

Rib stress fractures can occur in sports involving repetitive trunk muscle contractions. Few documented cases show rib fractures from repetitive upper-limb training. This report presents a case of a rib stress fracture from micro blunt trauma during bench press exercises. The patient was a 24-year-old elite female sprinter with a history of left navicular stress fracture and secondary amenorrhea treatment a year prior. She modified her bench press technique to involve bouncing the barbell on her rib cage. Within weeks, she experienced anterior chest pain, exacerbated by sneezing. Computed tomography revealed a fifth rib fracture with callus formation. After refraining from bench presses for 4 weeks, her chest pain subsided, allowing her to resume upper-limb training. When athletes performing bench press exercises experience chest pain, rib fractures should be considered, even without acute trauma. Additionally, research on the safety of the bouncing bench pressing technique is required.

Snack and Nutrient Intake Status of Top-Level Female University Athletes: A Cross-Sectional Study

Ensuring proper energy, nutrient intake, and sleep is vital for athlete health and competitiveness. Despite previous studies investigating the nutrient intake among top-level collegiate female athletes in Japan, the status of snack consumption remains unclear. This study addressed this gap by surveying 70 top-level female university athletes. The survey included a self-administered diet history questionnaire, a qualitative food intake frequency survey, and a survey on snack and dietary supplement use. The results revealed a low frequency of snack intake (2.1 ± 2.3 days/week), with 55.7% of athletes reporting snack consumption. The energy intake in the snack-intake group was significantly higher than that in the without-snack-intake group (31.5 ± 10.0 vs. 26.6 ± 9.92 kcal/kg of BM, p = 0.047). Similarly, carbohydrate intake was significantly higher in the snack-intake group than in the without-snack-intake group (4.84 ± 1.71 vs. 3.96 ± 1.65 g/kg of BM/day, p = 0.035). However, neither group reached the recommended value of 5-8 g/kg of BM/day during the medium training period. Overall, this study emphasizes inadequate energy intake even among athletes with a high snack intake frequency, highlighting the necessity to enhance overall food consumption and underscoring the importance of nutritional education for incorporating appropriate complementary meals to improve performance.

Concussion Rates in Youth Lacrosse Players and Comparison With Youth American Football

Background

There has been little focus on concussions in youth lacrosse players in the United States.

Purpose

To provide a descriptive analysis of the epidemiology and incidence of concussions in youth lacrosse and compare the results with well-documented analyses of concussions in youth American football.

Study Design

Descriptive epidemiology study.

Methods

Data on concussions in pediatric patients playing lacrosse from 2006 to 2019 were collected using the National Electronic Injury Surveillance System (NEISS). Weighted calculations and combined participation data obtained from membership in USA Lacrosse were used to estimate injury incidence. A comparison dataset was created using the NEISS data on youth football-related concussions. The cause of concussion was categorized into player-to-player, player-to-stick, player-to-ball, or player-to-ground contact.

Results

A total of 37,974 concussion injuries related to lacrosse were identified in players with a mean age of 14.5 ± 3.5 years; 70% of concussions occurred in boys. National participation in lacrosse increased from 2006 to 2011 by a mean of 10.3% annually, followed by a lower annual growth rate of 2.5% from 2012 to 2019. The overall incidence of concussion injuries increased over the study period (r = 0.314), with the incidence rate in boys being greater than that of girls from 2009 to 2013. The most common cause of concussion was player-to-ground contact for boys and player-to-ball or player-to-stick contact for girls. The mean annual concussion incidences in youth lacrosse and youth football were 443 and 355 per 100,000 participants, respectively.

Conclusion

Over the study period, 16% of lacrosse injuries were diagnosed as concussions, a higher mean annual incidence per 100,000 participants than that of youth football (443 vs 355). The cause of concussion was different based on sex, with higher rates of player-to-ball or player-to-stick contact in female players versus player-to-ground contact in male players.

Factors Associated With a Lateral Ankle Sprain in Young Female Soccer Players: A Prospective Cohort Study

Background

Previous studies have attempted to determine if certain risk factors can predict the occurrence of a lateral ankle sprain (LAS) in female soccer players. Unfortunately, there is limited evidence with regard to risk factors associated with an LAS in female soccer players.

Purpose

To identify intrinsic risk factors for an LAS among young female soccer players.

Study Design

Cohort study; Level of evidence, 2.

Methods

Participants were 161 young female soccer players in Japan who were evaluated for LAS risk factors during a preseason medical assessment. The assessment included anthropometric, joint laxity, joint range of motion, muscle flexibility, muscle strength, and balance measurements. Each athlete's history of LASs was also collected. The participants were monitored during a single-yearseason for LASs, as diagnosed by physicians.

Results

There were 26 instances of an LAS in 25 players (15.5%) during the season. Injured players were significantly more likely to have sustained a previous ankle sprain (P = .045) and demonstrated significantly worse balance than their peers without an LAS during the double- and single-leg balance tests (P = .008 for both). Athletes with lower hamstring-to-quadriceps muscle strength ratios were also significantly more likely to sustain an LAS (P = .02).

Conclusion

Poor balance, a low hamstring-to-quadriceps ratio, and a history of ankle sprains were associated with an increased risk of LASs in young female soccer players in the current study. These findings may be useful for developing a program to prevent LASs in this population.

Diagnostic value of shear-wave elastography for patellar tendinopathy in female volleyball and basketball athletes: a cross sectional case control study

OBJECTIVES

We aim to investigate the accuracy of shear-wave elastography (SWE) in diagnosing patellar tendinopathy in female volleyball and basketball players. In addition, we compared different parts of the patellar tendon and investigated the effects of different knee angles on elastography measurements.

METHODS

This cross-sectional case-control study evaluated 63 female athletes from professional basketball and volleyball teams (NCT06199583). Patellar tendinopathy diagnoses were made using clinical and ultrasonographic criteria. SWE measurements were taken at 30-degree knee flexion and extension. Rectangular regions of interest boxes were placed in three different parts of the tendon (proximal, middle, distal). The global SWE value was calculated by taking the mean of measurements in the three parts. Receiver operating characteristic (ROC) curves were used to identify significant cutoff points for SWE, and 2 × 2 tables were generated to determine sensitivity and specificity.

RESULTS

Thirteen (20.6%) of the 63 athletes were diagnosed with patellar tendinopathy. The ROC curves have identified different cutoff scores for SWE measurements. The SWE score of 130.75 from the proximal part showed the highest sensitivity of 89% and specificity of 80% (p < 0.001) with a 4.45 likelihood ratio at the 30-degree knee flexion. The likelihood ratio is 1.5 at a 30-degree angle and 1.65 at a 0-degree angle when measuring the entire tendon, whereas other portions indicate a ratio ranging from 1.12 to 1.73.

CONCLUSIONS

Shear-wave elastography is a reliable evaluation method for diagnosing patellar tendinopathy. It has more accuracy when applied to the proximal part and at 30-degree knee flexion compared to measurements taken at knee extension and other parts of the tendon.

Relative Age and Positive Youth Development in Youth Sport: Do Developmental Assets Play a Role in Creating Advantage Reversals in Female Soccer?

Relative age effects (RAEs) are commonly associated with advantages for older athletes. However, a variety of benefits attributed to 'advantage reversals' have been observed among relatively younger professional athletes. Considering psychosocial development as a proposed mechanism, the purpose of this study was twofold: (1) To explore an association between developmental assets (i.e., facilitators of positive youth development [PYD]) and RAEs; (2) To assess whether overall developmental asset levels are protective against sport dropout. The Developmental Assets Profile© was distributed to members of a one-year cohort of post-adolescent, female soccer players from Ontario, Canada. The presence of differences between groups of relatively older (H1; n = 64) and younger (H2; n = 57) participants and developmental asset scales were assessed using discriminant analysis. A binary logistic regression was conducted to assess whether overall developmental asset levels are protective against sport dropout, with consideration of relevant factors. Findings suggest that relatively younger, female players score higher in two internal categories: commitment to learning and positive values. The overall developmental asset scores were not found to be protective against dropout. This study provides preliminary, albeit cautious, support that 'advantage reversals' may be in part associated with enhanced PYD resulting from developmental sport experiences.

Female Athletes With Better Psychological Readiness Are at Higher Risk for Second ACL Injury After Primary ACL Reconstruction

BACKGROUND

Approximately 1 in 4 athletes returning to sports will sustain a second anterior cruciate ligament (ACL) injury. Psychological factors related to kinesiophobia, confidence, and psychological readiness are associated with second ACL injury; however, the evidence is conflicting.

HYPOTHESIS

Athletes who sustain a second ACL injury (ie, graft rupture or contralateral ACL rupture) within 2 years of ACL reconstruction (ACLR) would have greater kinesiophobia, less confidence, and lower psychological readiness prior to return to sport (RTS) compared with athletes who do not sustain a second ACL injury.

STUDY DESIGN

Secondary analysis of a prospective randomized trial.

LEVEL OF EVIDENCE

Level 3.

METHODS

A total of 39 female Level I/II athletes completed the following measures after postoperative rehabilitation and a 10-session RTS and second ACL injury prevention program: ACL Return to Sport after Injury (ACL-RSI) scale, the 11-item Tampa Scale of Kinesiophobia (TSK-11), and question 3 on the Knee injury and Osteoarthritis Outcome Score (KOOS) quality of life (QoL) subscale. Athletes were dichotomized based on whether they sustained a second ACL injury within 2 years of ACLR or not. Independent t tests determined group differences in TSK-11, KOOS-QoL, ACL-RSI, and the 3 individual components of the ACL-RSI (ie, emotions, confidence, risk appraisal).

RESULTS

Nine athletes sustained a second ACL injury (4 graft ruptures and 5 contralateral ACL ruptures). The group that sustained a second ACL injury had higher scores on the ACL-RSI (P = 0.03), higher on the risk appraisal questions of the ACL-RSI (P < 0.01), and met RTS criteria sooner than athletes who did not (P = 0.04). All second ACL injuries occurred in athletes who underwent primary ACLR with hamstring tendon autografts.

CONCLUSION

Athletes who sustained a second ACL within 2 years of ACLR had a more positive psychological outlook, higher scores on the specific questions related to the risk appraisal construct of the ACL-RSI, and met RTS criteria sooner than athletes who did not sustain a second ACL injury.

CLINICAL RELEVANCE

Counseling athletes about delaying RTS to reduce the risk of second ACL injury may be especially important in athletes who display high psychological readiness and meet RTS criteria sooner.

Menstrual cycle characteristics, perceived impact on performance, and barriers to communication: Perspectives of high-performance adolescent athletes in Singapore

The purpose of this study was to examine the menstrual cycle (MC) characteristics, explore the impact on performance, and identify barriers to and facilitators of MC-related communication among high-performance female adolescent athletes in Singapore. Ninety athletes (15.4 ± 1.8 years) from multiple sports completed an online questionnaire. Eighty-four athletes were postmenarcheal (menarcheal age 11.9 ± 1.3 years), including two who were using an oral contraceptive pill (OCP). Secondary amenorrhea, current or history of, was self-reported in 16% of athletes. Sixty-two percent and 67% of non-OCP athletes perceived that the MC affected their ability to train and compete, respectively. Athletes preferred speaking to a parent (85%) and a female figure (67%) about MC-related concerns. Through thematic analysis, three barriers to communication were constructed: (1) pervasive menstrual stigma, (2) constraints of the training environment, and (3) the low value placed on MC-related conversations. Two facilitators of communication were constructed: (1) respect athletes' individual experiences as menstruating girls and (2) foster a safe space for MC-related conversations. Findings demonstrated that menstrual irregularities are common in adolescent athletes and screening for MC disorders, particularly primary amenorrhea should be undertaken in this population, with clear support pathways for management including symptom mitigation. To support athletes in raising MC-related concerns when needed, structured communication pathways that consider individual preferences and involve a (female) point of contact should be established within the training environment. Improving menstrual health literacy among adolescent athletes before any misinformation or negative perceptions are firmly established may contribute to longevity in their athletic careers.

Female Athletes and the Menstrual Cycle in Team Sports: Current State of Play and Considerations for Future Research

Over the past ten years there has been a dramatic rise in female sport participation and accompanying female professional national leagues across multiple sports, yet research has not followed suit. Although there are known variations between female and male physiology, training protocols in female sport are predominantly underpinned by research undertaken in male athletes. The hormonal variability experienced by women across the menstrual cycle, as well as the menstrual cycle variability between women, may contribute to the complexity of conducting rigorous physiological studies, leading to a paucity of robust sports-specific research that can be confidently applied to female athletes. Moreover, barriers exist in female sport that potentially limit the ability to conduct research, including the lack of full-time programs and limited resources. Recently, there has been increased interest in the potential effects of fluctuations in the female sex hormones, progesterone and oestrogen, on sport performance across different phases of the menstrual cycle. However, current research evaluating the menstrual cycle and physical performance (such as strength, speed, aerobic fitness, and athletes' perception of their performance) have shown inconsistent results. Additionally, methodological design across studies has shown little consistency, making it difficult to draw firm conclusions, which potentially prevents female athletes optimising their physical and sporting performance. It further impacts coaches and sports science researchers in their ability to provide appropriate training recommendations and educational opportunities. It is important to progress in female athlete research with an understanding of how the unique physiology of female athletes may influence their ability to physically perform in their respective sport, which requires representation in sports science research. This paper will provide an overview on current evidence and limitations within menstrual cycle research and provide considerations and directions for future research in this space within team sports.

Athlete Sleep Behavior Questionnaire in Japanese (ASBQ-J): An Adaptation and Validation Study

Purpose

The Athlete Sleep Behavior Questionnaire (ASBQ) is an 18-item self-reported questionnaire that can be used to screen for sleep disorders in athletes and assess environmental, behavioral, and sports-related factors along with sleep disorders. This study aimed to analyze the reliability and validity of the ASBQ translated into Japanese (ASBQ-J).

Patients and Methods

111 female collegiate athletes completed both the initial test and retest. Independent variables were what kind of sports they perform, level as an athlete, grade (freshman, sophomore, junior, senior), and age. The reliability of the survey was assessed using Cronbach's alpha and intraclass correlation, and Pearson's correlation coefficient was calculated to determine the correlation between the total ASBQ scores and three components which were routine/environmental, behavioral, and sports factors.

Results

A total of 37.8% of athletes had ASBQ scores equal or less than 36 indicating good sleep. However, 19.8% of athletes scored more than 42, indicating poor sleep. Cronbach alpha was 0.62 and 0.65 for test and retest, respectively. Intraclass correlation was 0.78 (P < 0.01), indicating sufficient internal consistency and test-retest validity. Mean ASBQ scores were 38.5 ± 5.0 and 37.0 ± 6.5 for test and retest, respectively, and it was not significantly different between the two groups (P = 0.37). The correlation coefficients between the ASBQ-J and component scores were all statistically significant (all P < 0.01).

Conclusion

ASBQ-J is a reliable questionnaire for assessing sleep disorders in athletes whose primary language is Japanese.

Energy balance and energy availability of female basketball players during the preparation period

OBJECTIVE

To determine the level of energy balance and energy availability (EA) in female basketball players during the preparation period.

METHODS

Fifteen basketball players (age: 19.53 ± 1.3 years; height: 173.6 ± 8.95 cm; weight: 67.55 ± 14.34 kg; training experience: 9.6 ± 2.7 years) and 15 age and body mass index-matched controls (age: 19.53 ± 1.1 years; height: 169.4 ± 5.06 cm; weight: 63.10 ± 6.14 kg) participated in the study. Resting metabolic rate (RMR) and body composition were measured by the indirect calorimetric method and dual-energy x-ray absorptiometry, respectively. A 3-day food diary was used to determine macronutrients and energy intake while a 3-day physical activity log was used to determine energy expenditure. Independent Samples t-test was used for data analysis.

RESULTS

The daily energy intake and expenditure of female basketball players were 2136.5 ± 594.9 kcal·day-1 and 2953.8 ± 614.5 kcal·day-1, respectively, indicating 817 ± 779 kcal·day-1 of negative energy balance. One hundred percent and 66.6% of the athletes failed to meet the carbohydrate and protein intake recommendations, respectively. EA of female basketball players was 33.04 ± 15.69 kcal·fat free mass-1·day-1 and the percentages of athletes who had negative energy balance, low EA, and reduced EA were 80%, 40%, and 46.7%, respectively. However, despite the low and decreased EA, the measured RMR to predicted RMR ratio (RMRratio) was 1.31 ± 0.17 and the body fat percentage (BF%) was 31.00 ± 5.21%.

CONCLUSION

This study shows that female basketball players have a negative energy balance during the preparation period which can be partly explained by insufficient carbohydrate intake. Although most of the athletes experienced low or reduced EA during the preparation period, the physiologically normal RMRratio and relatively high BF% indicate that this is a transient situation. In this regard, strategies to prevent the development of low EA and negative energy balance during the preparation period will contribute to positive training adaptations throughout the competition period.

Effects of pregnancy and lactation on muscle-tendon morphology

Pregnancy and lactation hormones have been shown to mediate anatomical changes to the musculoskeletal system that generates animal movement. In this study, we characterize changes in the medial gastrocnemius muscle, its tendon and aponeuroses that are likely to have an effect on whole animal movement and energy expenditure, using the rat model system, Rattus norvegicus. We quantified muscle architecture (mass, cross-sectional area, and pennation angle), muscle fiber type and diameter, and Young's modulus of stiffness for the medial gastrocnemius aponeuroses as well as its contribution to Achilles tendon in three groups of three-month-old female rats: virgin, primiparous pregnant, and primiparous lactating animals. We found that muscle mass drops by 23% during lactation but does not change during pregnancy. We also found that during pregnancy muscle fibers switch from Type I to IIa and during lactation from Type IIb to Type I. The stiffness of connective tissues that has a demonstrated role in locomotion, the aponeurosis and tendon, also changed. Pregnant animals had a significantly less stiff aponeurosis. However, tendon stiffness was most affected during lactation, with a significant drop in stiffness and interindividual variation. We propose that the energetic demands of locomotion may have driven the evolution of these anatomical changes in muscle-tendon units during pregnancy and lactation to ensure more energy can be allocated to fetal development and lactation.

Association of Systemic Hormonal Contraceptives With Reconstruction Procedures for Patellar Instability

Background

Previous research suggests that estrogen plays a role in increased ligamentous laxity observed within the female population. Whereas many studies have sought to evaluate the impact of exogenous estrogen on anterior cruciate ligament injuries, research has not yet explored its impact on the medial patellofemoral ligament. Furthermore, less is known about the role of exogenous progesterone on ligamentous structures.

Purpose

To determine whether women prescribed systemic estrogen (ethinyl estradiol) or progesterone (norgestimate or etonogestrel) hormonal contraceptives had an increased risk of undergoing reconstruction surgery for patellar instability compared with women without a prescription for systemic hormonal contraceptives.

Study Design

Cross-sectional study; Level of evidence, 3.

Methods

The TriNetX Research Network database was queried using International Classification of Disease and Common Procedural Terminology codes for women aged 15 to 26 years who underwent reconstruction procedures for patellar instability between 2012 and 2022. Women were grouped according to whether they had a coded prescription for a systemic hormonal contraceptive containing either ethinyl estradiol or etonogestrel; controls were matched by age, sex, race, and ethnicity. The relative risk (RR) of undergoing reconstruction for patellar instability was determined for each contraceptive.

Results

After 1-to-1 propensity score matching, 0.054% (525/980,878) of women prescribed a systemic contraceptive containing ethinyl estradiol underwent reconstruction procedures for patellar instability compared with 0.043% (417/980,878) of controls (RR, 1.3; 95% CI, 1.1-1.4; P = .0004). Likewise, 0.058% (67/116,260) of women prescribed a form of systemic contraceptive containing only etonogestrel underwent reconstruction procedures for patellar instability compared with 0.026% (30/116,260) of controls (RR, 2.2; 95% CI, 1.5-3.4; P = .0002).

Conclusion

Female patients prescribed systemic contraceptives containing estrogen or progesterone had an increased rate of reconstruction procedures for patellar instability.

Manipulation Under Anesthesia and/or Lysis of Adhesions After Anterior Cruciate Ligament Reconstruction in Female Basketball Players: Does Race Play a Role?

BACKGROUND

Arthrofibrosis can limit function and return to sport after anterior cruciate ligament (ACL) reconstruction. Previously reported risk factors for developing arthrofibrosis after ACL reconstruction include female sex, age <18 years, time from injury to surgery <28 days, concomitant meniscal repair, prolonged immobilization, and genetic factors. There is a lack of evidence regarding whether race plays a significant role.

HYPOTHESIS

The risk of undergoing manipulation under anesthesia (MUA) and/or lysis of adhesions (LOA) after primary ACL reconstruction with bone-patellar tendon-bone (BTB) autograft in female basketball players is higher in African American players than in White players.

STUDY DESIGN

Case-control study; Level of evidence, 3.

METHODS

Using a computerized relational database, the authors identified competitive female basketball players who underwent primary ACL reconstruction with BTB autograft by the senior author over a 13-year period. Data previously entered from examinations and surgical findings were reviewed retrospectively. Univariate statistics and multivariable logistic regression were used to assess the relationship between undergoing subsequent MUA and/or LOA and study predictors.

RESULTS

A total of 186 knees (114 African American knees and 72 White knees) met inclusion criteria. The overall rate of MUA and/or LOA was 8.6%. Thirteen African American knees (11.4%) and 3 White knees (4.2%) underwent MUA and/or LOA for treatment of arthrofibrosis. No study predictor was found to have a statistically significant relationship with the rate of MUA and/or LOA on univariate analysis. However, when controlling for body mass index and previously described risk factors (age <18 years, time from injury to surgery ≤28 days, and concomitant meniscal repair) in the logistic regression model, the authors found that MUA and/or LOA was more likely in African American (odds ratio, 4.01 [95% CI, 1.01-15.92]; P = .049) than in White female players and in patients who underwent ACL reconstruction within 28 days of injury (odds ratio, 4.01 [95% CI, 1.18-13.57]; P = .026) compared with those with surgery delayed beyond 28 days.

CONCLUSION

In female basketball players, the present study found a statistically significantly increased risk for undergoing MUA and/or LOA after primary ACL reconstruction with BTB autograft in African American females compared with White females and in patients who underwent ACL reconstruction within 28 days of injury.

Wellness Following Wins and Losses Based on Psychological Hardiness in Division I Women's Lacrosse

Psychological hardiness encompasses three components: commitment, control, and challenge, and illustrates how individuals respond to stressors. Analyzing athletes' responses to wins and losses, depending on their psychological hardiness level, may provide insight of the impact of game outcome on student-athlete wellness. The purpose of this study was to examine postgame subjective wellness scores based on level of psychological hardiness following wins and losses in collegiate female lacrosse athletes. Players (n = 17) took the Dispositional Resilience Scale Scale-15 (DRS-15) at the start of the academic year and were grouped based on hardiness level: above average (AH) and below average (BA). Participants took a daily wellness survey rating their overall wellness, energy level, muscle soreness, stress level, and sleep quality. RM-ANOVA indicated no difference in post-game wellness scores between hardiness groups (Lambda(5,11) = 1.073, p = .426, ES = .328), by game outcome (Lambda(5,11) = 2.361, p = .109, ES = .518), or an interaction between hardiness and outcome of game (Lambda(5,11) = 1.421, p = .291, ES = .392). No hardiness group differences were found for overall wellness or sub-scores. These results show subjective wellness scores decrease collectively after a loss versus a win but refute prior studies as hardy players did not experience significantly less stress than their less hardy counterparts. Future studies should be conducted to assess wellness after differing game outcomes over many seasons to assist coaching staff on the subjective, psychological impacts of game.

Position comparison of sport-related concussions in female youth soccer players

OBJECTIVES

Youth soccer participation, particularly among females, continues to grow worldwide. With the high incidence of sport-related concussion (SRC) in soccer, it is important to investigate if SRC occurs disproportionally by positions. Our hypothesis was to see no positional differences in SRCs, SRC-related characteristics, and outcomes among in female youth soccer athletes.

METHODS

Data were prospectively collected from participants at a single sports medicine institution between August 2015-April 2021. Female participants aged 8-18 diagnosed with SRC sustained during an organized soccer practice, scrimmage, or game were separated into 4 groups based on position: Forward, Midfielder, Defender, and Goalkeeper. Demographics, medical history, injury-related details, and outcomes were reviewed. A chi-square test or Fisher's exact test was used for categorical variables. Continuous variables were compared with Mann-Whitney or Kruskal-Wallis test.

RESULTS

Two hundred fourteen participants were included: 52 Forwards, 65 Midfielders, 63 Defenders, and 34 Goalkeepers. There were no significant differences between the groups in age, race, ethnicity, or previous concussion history. Differences in mechanism existed with Goalkeepers most commonly reporting Head to Body Part. Goalkeepers, which make up 1/11 of the total positions on the field, had a significantly higher proportion of SRCs compared to Field Positions. (9.1% vs 15.9%)At 3-month post-enrollment, there were no significant differences in reported symptoms or return-to-play between the different positions.

CONCLUSION

In youth female soccer players, goalkeepers sustained a higher proportion of sport-related concussions compared to field players based upon the composition of a soccer team. The mechanism of injury also differed among the different soccer positions. However, no differences in concussion characteristics, outcomes, or RTP were seen across the different soccer positions.

Low energy availability reduces myofibrillar and sarcoplasmic muscle protein synthesis in trained females

Low energy availability (LEA) describes a state where the energy intake is insufficient to cover the energy costs of both exercise energy expenditure and basal physiological body functions. LEA has been associated with various physiological consequences, such as reproductive dysfunction. However, the effect of LEA on skeletal muscle protein synthesis in females performing exercise training is still poorly understood. We conducted a randomized controlled trial to investigate the impact of LEA on daily integrated myofibrillar and sarcoplasmic muscle protein synthesis in trained females. Thirty eumenorrheic females were matched based on training history and randomized to undergo 10 days of LEA (25 kcal · kg fat-free mass (FFM)-1  · day-1 ) or optimal energy availability (OEA, 50 kcal · kg FFM-1  · day-1 ). Before the intervention, both groups underwent a 5-day 'run-in' period with OEA. All foods were provided throughout the experimental period with a protein content of 2.2 g kg lean mass-1  · day-1 . A standardized, supervised combined resistance and cardiovascular exercise training programme was performed over the experimental period. Daily integrated muscle protein synthesis was measured by deuterium oxide (D2 O) consumption along with changes in body composition, resting metabolic rate, blood biomarkers and 24 h nitrogen balance. We found that LEA reduced daily integrated myofibrillar and sarcoplasmic muscle protein synthesis compared with OEA. Concomitant reductions were observed in lean mass, urinary nitrogen balance, free androgen index, thyroid hormone concentrations and resting metabolic rate following LEA. These results highlight that LEA may negatively affect skeletal muscle adaptations in females performing exercise training. KEY POINTS: Low energy availability (LEA) with potential health and performance impairments is widespread among female athletes. We investigated the impact of 10 days of LEA on daily integrated myofibrillar and sarcoplasmic muscle protein synthesis in young, trained females. We show that LEA impairs myofibrillar and sarcoplasmic muscle protein synthesis in trained females performing exercise training. These findings suggest that LEA may have negative consequences for skeletal muscle adaptations and highlight the importance of ensuring adequate energy availability in female athletes.

Estimated Energy Expenditures and Energy Intakes of International Female Rugby Sevens Players in Five Days of a Training Camp and Competition Preparation

To understand the energy balance of international female rugby sevens (R7s) players in applied environments, this study estimated the energy intakes (EI) and total daily estimated energy expenditures (TDEE) during a five-day training camp (TRAIN) and phase of competition preparation (COMP) of equal duration. Tri-axial accelerometer devices were worn throughout both scenarios to estimate TDEE, whereas EI was estimated via self-reported food diaries. Energy deficits of -47% (TDEE_TRAIN: 14.6 ± 1.6 MJ·day^-1, EI_TRAIN: 7.7 ± 0.9 MJ·day^-1, p ≤ 0.001, d = 5.1) and -50% (TDEE_COMP: 15.5 ± 1.6 MJ·day^-1, EI_COMP: 7.7 ± 1.0 MJ·day^-1, p ≤ 0.001, d = 5.7) were observed throughout TRAIN (n = 11; age: 25 ± 4 years, height: 170 ± 6 cm, weight: 71 ± 7 kg) and COMP (n = 8; age: 25 ± 3 years, height: 172 ± 5 cm, weight: 72 ± 6 kg), respectively. Carbohydrate intakes were below the lower range of sports nutrition recommendations in both TRAIN (-62%; 2.3 ± 0.3 g·kg^-1 BM, p ≤ 0.001) and COMP (-60%; 2.4 ± 0.5 g·kg^-1 BM, p ≤ 0.001). For protein (TRAIN: 1.7 ± 0.4 g·kg^-1 BM, COMP: 1.5 ± 0.1 g·kg^-1 BM), intakes met the lower range of recommendations. Fat intake exceeded recommendations of the percentage of total EI (COMP: 39 ± 5%). Accordingly, the dietary strategies of international female R7s players may warrant optimization, as carbohydrate and fat intakes were less than optimal when compared to current performance-based sports nutrition guidelines.

Carbohydrate intake in young female cross-country skiers is lower than recommended and affects competition performance

Purpose

(1) To evaluate if energy availability (EA), macronutrient intake and body composition change over four training periods in young, highly trained, female cross-country skiers, and (2) to clarify if EA, macronutrient intake, body composition, and competition performance are associated with each other in this cohort.

Methods

During a one-year observational study, 25 female skiers completed 3-day food and training logs during four training periods: preparation, specific preparation, competition, and transition periods. A body composition measurement (bioimpedance analyzer) was performed at the end of the preparation, specific preparation, and competition periods. Competition performance was determined by International Ski Federation (FIS) points gathered from youth national championships.

Results

EA (36-40 kcal·kg FFM^-1·d^-1) and carbohydrate (CHO) intake (4.4-5.1 g·kg^-1·d^-1) remained similar, and at a suboptimal level, between training periods despite a decrease in exercise energy expenditure (p = 0.002) in the transition period. Higher EA (r = -0.47, p = 0.035) and CHO intake (r = -0.65, p = 0.002) as well as lower FM (r = 0.60, p = 0.006) and F% (r = 0.57, p = 0.011) were associated with lower (better) FIS-points. CHO intake was the best predictor of distance competition performance (R² = 0.46, p = 0.004).

Conclusions

Young female cross-country skiers had similar EA and CHO intake over four training periods. Both EA and CHO intake were at suboptimal levels for performance and recovery. CHO intake and body composition are important factors influencing competition performance in young female cross-country skiers.

Long-term development of performance, physiological, and training characteristics in a world-class female biathlete

Purpose

The purpose of this study is to investigate the long-term development of performance, physiological, and training characteristics in a world-class female biathlete, with emphasis on differences between junior and senior athlete seasons.

Methods

The participant is a highly decorated female biathlete with 22 (10 gold) medals from international championships and 28 individual World Cup wins. Performance development (ages 17-33), physiological tests (ages 22-33), and day-to-day physical and shooting training (ages 17-33) were analyzed. Training data were systemized by endurance [low-intensity training (LIT), moderate-intensity training (MIT), and high-intensity training (HIT)], exercise mode, and strength training. Shooting training recorded for each session included the number of shots fired during rest, LIT, MIT, HIT, or competitions and time spent on dry fire training.

Results

The annual volume of physical training (409-792 h·season^-1) and number of shots fired (1,163-17,328 shots·season^-1) increased from the age of 17 to 28 followed by a subsequent reduction in physical training (range 657-763 h·season^-1) and shots fired (13,275-15,355 shots·season^-1) during the seasons of peak performance at ages 31-33. Maximal oxygen uptake in roller ski skating increased by 10% (62.9-69.2 ml·kg^-1·min^-1) from the age of 22 to 27. The physical training volume was 48% higher (694 ± 60 vs. 468 ± 23 h·season^-1, P = .030), with 175% more shots fired (14,537 ± 1,109 vs. 5,295 ± 3,425 shots·season^-1, P = .016) as a senior athlete than a junior athlete. In the physical training, these differences were mainly explained by higher volumes of LIT (602 ± 56 vs. 392 ± 22 h·season^-1, P = .032) and MIT (34 ± 1 vs. 7 ± 2 h·season^-1, P = .001) but less HIT (27 ± 1 vs. 42 ± 3 h·season^-1, P = .006) as a senior than a junior. In line with this, shooting training as a senior included more shots fired both at rest (5,035 ± 321 vs. 1,197 ± 518 shots·season^-1, P = .011) and during LIT (7,440 ± 619 vs. 2,663 ± 1,975 shots·season^-1, P = .031), while a smaller insignificant difference was observed in the number of shots fired in connection with MIT, HIT, and competitions (2,061 ± 174 vs. 1,435 ± 893 shots·season^-1, P = .149).

Conclusions

This study provides unique insights into the long-term development of physical and shooting training from junior to senior in a world-class female biathlete. The major differences in training characteristics between junior and senior athlete seasons were higher sport-specific volumes of LIT and MIT and less HIT. These differences were accompanied by more shooting training, particularly at rest, and in connection with LIT.

What place does elite sport have for women? A scoping review of constraints

Introduction

Despite increases in participation and raised attention for girls and women in sports, female sport is still based on male evidence that ignores gendered differences and experiences of unequal treatment and marginalization from grassroots to elite sport. This paper aimed to critically interrogate the place that women have in the male preserve of elite sport by conducting a two-part study.

Methods

First, we provided a brief sociohistorical analysis of gender in sport as a means to move away from a decontextualized and universalized approach dominating in sport science literature. We then conducted a scoping review following PRISMA-ScR guidelines to synthesize existing sport science literature that implemented Newell's constraints-led approach to examine elite performance.

Results

Ten studies were identified, none of which collected demographic data or centred on female athletes and the effects of sociocultural constraints on their performance. Instead, male-centred, masculine sports and physiological profiles dominated the identified studies.

Discussion

We discussed these results considering critical sport research and cultural sport psychology literature to offer an integrative, interdisciplinary approach to advocate for more culturally sensitive, context-specific interpretations of gender as a sociocultural constraint. We put forth a call to action for sport science researchers, practitioners, and decision-makers to move away from implementing male evidence in female sport and attend to the unique needs of female athletes. Practical suggestions aimed to help stakeholders reimagine elite sport by celebrating these [potential] differences as strengths for promoting gender equity in sport.

Lower Limb Anthropometric Profiling in Professional Female Soccer Players: A Proof of Concept for Asymmetry Assessment Using Video Analysis

The objective was to evaluate the clinical joint and limb measures in professional female soccer players. The study was a cross-sectional observational design. It was a preseason clinical setting. The inclusion criteria were outfield professional female soccer players, based in the UK, competing in the highest English league. The exclusion criteria included players who had had surgery in the last six months or had missed a single training session or match due to injury in the previous three months. In terms of the outcome measures, the dependent variables were the true limb length, ankle dorsiflexion, knee flexion and extension, hip flexion, extension, internal rotation and external rotation, and straight leg raise measured using video analysis software. Additionally, passive clinical knee and ankle stability tests were conducted. The independent variables were leg dominance and playing position (defender, midfielder, and attacker). For the results, all the ROM measurements demonstrated limb symmetry (p = 0.621). However, there were significant main effects of the playing position on the ankle dorsiflexion and hip internal rotation, with defenders demonstrating a significantly reduced range of motion in comparison to midfielders and attackers. A notable finding from the bilateral passive stability measures was that 38.3% of players exhibited ankle talar inversion instability when using a talar tilt. In conclusion, bilateral differences do not appear to be apparent in this population; however, positional differences may occur in the ankle and hip range of motion measures. A high proportion of this population may present with passive ankle inversion instability. Future research should consider whether this leads to a higher risk of injury in this population.

A case-control study of tackle based head impact event (HIE) risk factors from the first three seasons of the National Rugby League Women's competition

Objective

The tackle is the most injurious event in rugby league and carries the greatest risk of concussion. This study aims to replicate previous research conducted in professional men's rugby league by examining the association between selected tackle characteristics and head impact events (HIEs) in women's professional rugby league.

Methods

We reviewed and coded 83 tackles resulting in an HIE and every tackle (6,318 tackles) that did not result in an HIE for three seasons (2018-2020) of the National Rugby League Women's (NRLW) competition. Tackle height, body position of the tackler and ball carrier, as well as the location of head contact with the other player's body were evaluated. Propensity of each situation that caused an HIE was calculated as HIEs per 1,000 tackles.

Results

The propensity for tacklers to sustain an HIE was 6.60 per 1,000 tackles (95% CI: 4.87-8.92), similar to that of the ball carrier (6.13 per 1,000 tackles, 95% CI: 4.48-8.38). The greatest risk of an HIE to either the tackler or ball carrier occurred when head proximity was above the sternum (21.66 per 1,000 tackles, 95% CI: 16.55-28.35). HIEs were most common following impacts between two heads (287.23 HIEs per 1,000 tackles, 95% CI: 196.98-418.84). The lowest propensity for both tackler (2.65 per 1,000 tackles, 95% CI: 0.85-8.20) and ball carrier HIEs (1.77 per 1,000 tackles, 95% CI: 0.44-7.06) occurred when the head was in proximity to the opponent's shoulder and arm. No body position (upright, bent or unbalanced/off feet) was associated with an increased propensity of HIE to either tackler or ball carrier.

Conclusions

In the NRLW competition, tacklers and ball carriers have a similar risk of sustaining an HIE during a tackle, differing from men's NRL players, where tacklers have a higher risk of HIEs. Further studies involving larger samples need to validate these findings. However, our results indicate that injury prevention initiatives in women's rugby league should focus on how the ball carrier engages in contact during the tackle as well as how the tackler executes the tackle.

Training Load Quantification in Women's Elite Football: A Season-Long Prospective Cohort Study

The aim of this study was to investigate (1) if there are differences in training load and intensity between the different training days within a microcycle and (2) if training load and intensity within the different training days are stable over the course of a season. Data were collected over a full season from a team in the women's premier division in Norway. External load (total distance, high-speed-running distance, sprint distance, and the combined number of accelerations and decelerations [ACCDEC]) was assessed using a 10-Hz GPS system with a built-in accelerometer. Internal load was assessed through session rating of perceived exertion, which was multiplied with session duration (session rating of perceived exertion-load). Training days were classified in relation to their proximity to the upcoming match day (MD): MD - 4, MD - 3, MD - 2, and MD - 1. Contents on these days were standardized according to a weekly periodization model followed by the coaching staff. Differences between training days were analyzed using a linear mixed-effects model. All training days were significantly different from each other across multiple variables. ACCDEC values were highest on MD - 4 (147.5 [13.0] ACCDEC count), and all distance variables were highest on MD - 3. All measures of training load were significantly reduced from MD - 3 to MD - 2 (effect size [ES] = 1.0-4.1) and from MD - 2 to MD - 1 (ES = 1.6-4.3). A significant negative effect across the season was observed for session rating of perceived exertion-load and ACCDEC (ES = 0.8-2.1). These results provide evidence that elite female football teams can be successful in differentiating training load between training days when implementing a weekly periodization approach.

The effects of taurine ingestion on anaerobic and physiological performance in female rugby players

The purpose of this study was to investigate the acute effect of low, moderate, or high doses of taurine on anaerobic and physiological performance in female rugby players. A total of 16 sub-elite female rugby athletes (21.3 ± 1.5 yr, 168.0 ± 4.9 cm, 62.1 ± 3.5 kg mean ± SD) participated in this research. Following familiarization, participants attended 4 successive tests separated by 72 h in a randomized, counter-balanced, crossover research design. Following an over night fast, participants completed a 5-min 60 Watt warm-up followed by a 30-s Wingate anaerobic test on a cycle ergometer after ingestion of either 2 g taurine (LOWTAU), 4 g (MODTAU), 6 g (HIGHTAU) or placebo (PLA) 1 h before the test. Peak (PP) and mean power (MP) along with heart rate (HR), rating of perceived exertion (RPE), capillary lactate and blood glucose were measured. LOWTAU did not affect PP, MP, HR, lactate and glucose compared to PLA (p > 0.05), while MODTAU improved MP and HIGHTAU improved PP and MP compared to PLA and LOWTAU (p < 0.05). MODTAU and HIGHTAU had little effect on HR, blood lactate and glucose (p > 0.05). A single dose of taurine (MODTAU or HIGHTAU) 1 h prior to competition or training would provide an ergogenic effect on subsequent power output.

Physical Match Demands of International Women's Rugby Union: A Three-Year Longitudinal Analysis of a Team Competing in The Women's Six Nations Championship

There is a paucity of studies describing the physical match demands of elite international women's rugby union, which limits coaches' ability to effectively prepare players for the physical demands required to compete at the elite level. Global positioning system technologies were used to measure the physical match demands of 53 international female rugby union players during three consecutive Women's Six Nations Championships (2020-2022), resulting in 260 individual match performances. Mixed-linear modelling was used to investigate differences in physical match demands between positions. Significant effects (p < 0.05) of the position were observed for all variables, with the exception of relative distances (m.min^-1) at velocities of 1.01-3.00 m·s^-1 (p = 0.094) and 3.01-5.00 m·s^-1 (p = 0.216). This study provides valuable data on the physical match demands of elite international women's rugby union match play that may aid practitioners in the physical preparation of players to compete at this level. Training methodologies for elite-level female rugby union players should consider the unique demands across positional groups with specific considerations of high-velocity running and collision frequency.

Circulating plasma levels of miR-106b-5p predicts maximal performance in female and male elite kayakers

Introduction

Plasma miR-106b-5p levels have been described as an exercise performance predictor in male amateur runners, although no information is available about female athletes. The aim of this study was to analyze the predictive value on sports performance of plasma miR-106b-5p levels in elite female and male kayakers at the beginning and at the end of a training macrocycle, as well as the potential underlying molecular mechanisms using an in silico approach.

Materials and Methods

Eight elite male (26.2 ± 3.6 years) and seven elite female (17.4 ± 0.5 years) kayakers from the Spanish national team. Two fasting blood samples were collected, starting point of the season (A) and maximum fitness level (B). Circulating plasma levels of miR-106b-5p were analyzed by RT-qPCR. Maximal 500 m performance was recorded at B.

Results and Discussion

miR-106b-5p levels had no differences between A and B neither in women nor in men. In men but not in women, miR-106b-5p levels showed a negative significant correlation with performance in B which highlights its predictive value for performance. However, in women, progesterone emerged as a determinant and the ratio miR-106b-5p/progesterone showed a significant negative correlation with performance. In silico analysis reveals potential targets in a number of genes of relevant to exercise.

Conclusions

miR-106b-5p emerges as a biomarker of athletic performance in men and in women, if the menstrual cycle is considered. This highlights the need to analyze molecular response to exercise in men and women separately, and considering the stage of the menstrual cycle in women as a relevant factor.

Effect of incline versus block heel-raise exercise on foot muscle strength and vertical jump performance - an 11-week randomized resistance training study

Strengthening the toe flexors and ankle plantar flexors may improve vertical jump performance. One exercise that may be effective for concurrently strengthening these muscles is heel-raises performed on an incline. The purpose of this study was to investigate the effects of incline versus conventional (block) heel-raise exercise on hallux and II-V digit flexor strength, vertical jump performance, and ankle plantar flexor strength. Thirty-three female volleyball players were randomly allocated to perform incline (n = 17) or block (n = 16) heel-raise exercise for 11-weeks. Participants' toe flexor strength, countermovement jump, approach jump, and ankle plantar flexor strength were assessed before, after 7 weeks, and after 11 weeks of exercise. There were no significant time-by-group interactions for any variable (p > 0.05). However, both groups improved their hallux flexor strength (Δ0.27 ± 0.50 N·kg-1; p < 0.05), and vertical countermovement (Δ1.2 ± 2.3 cm; p < 0.05) and approach (Δ1.9 ± 2.6 cm; p < 0.05) jump height from pre- to post-test. No changes were observed in the ankle plantar flexor or II-V digit flexor strength (n > 0.05). Both incline and conventional heel-raises improve toe flexor strength. Practitioners seeking to improve individuals' foot function may consider incorporating incline or block heel-raises.

The "Mother Load" and Return to Sport: A Case Report of Returning to Professional Netball Following Cesarean Section

Background

Increasing numbers of elite female athletes are competing in professional sport, and many wish to become pregnant and return to competitive sport after childbirth. Athletes have a higher risk of pelvic floor dysfunction (PFD) than non-athletes (54% versus 7%) and there is also an increased prevalence in post-partum women compared to nulliparous women (35% versus 2.8-7.9%). Additionally, PFD has been shown to influence athletic performance. High quality evidence for elite athletes is lacking, and there are no exercise guidelines specifically for these women to prepare or effectively guide their safe return to sport (RTS). The purpose of this case report is to detail the management of an elite athlete who presented following cesarean section (CS) with the goal of RTS within 16 weeks.

Case Description

A 27-year-old primiparous Caucasian professional netballer presented at four weeks post- caesarean section (CS) for RTS screening and assessment of pelvic floor muscle (PFM) function. Assessment included readiness and fear of movement screening, dynamic pelvic floor muscle function, structural integrity of the CS wound, levator hiatal dimensions, bladder neck descent, and early global neuromuscular screening. Measures were collected at four weeks, eight weeks, and six months post-partum. The post-partum athlete demonstrated alterations in pelvic floor muscle function, reduced lower limb power and psychological readiness. A functionally staged dynamic and sport specific pelvic floor muscle training program was implemented and adapted to the patient for her early post-partum timeline.

Results

Rehabilitation strategies were effective in achieving the primary outcome of RTS at 16 weeks post-partum with no adverse events reported at 6 months follow-up.

Discussion

This case highlights the need for a holistic and individualised RTS management approach that includes women's and pelvic health risk factors in a professional athlete.

Level of Evidence

5.

The architectural characteristics of the hamstring muscles do not differ between male and female elite-level rugby union players

Purpose: To determine whether differences exist in the architectural characteristics of the hamstring muscles of elite-level male and female rugby union players. Methods: Forty elite-level rugby union players (male n = 20, female n = 20) participated in this cross-sectional study. A sonographer acquired static ultrasound images using a 92 mm linear transducer to quantify (via a semi-automated tracing software tool) the architectural characteristics (muscle length, fascicle length, pennation angle, and muscle thickness) of the biceps femoris long head and semimembranosus muscles of participants' left limb. Muscle length and muscle thickness of the biceps femoris short head and semitendinosus muscles of participants' left limb were also quantified. Bonferroni adjusted independent samples t-tests were performed to evaluate whether differences exist in the architectural characteristics of the hamstring muscles of elite-level male and female rugby union players. Results: There were no significant differences in fascicle length or pennation angle of the hamstring muscles of elite-level male and female rugby union players. Some significant differences in muscle thickness (biceps femoris short head, and semimembranosus) and muscle length (biceps femoris short head, biceps femoris long head, semitendinosus, and semimembranosus) were observed; in all cases the male players had thicker and longer muscles. Conclusion: At a group level, hamstring muscle fascicle length and pennation angle are unlikely to be a sex-specific intrinsic risk factor for Hamstring strain injuries.

Longitudinal monitoring of workloads in women's division I (DI) collegiate basketball across four training periods

Women's collegiate basketball is a fast-growing, dynamic sport that spans 8 or more months, with athletes competing in 30 + games in a season. The aim of this study was to quantify and profile the external load of practices and games during a Power-5 DI Women's Collegiate Basketball season. Specifically, Average PlayerLoad (PL), PlayerLoad per minute (PL*min^-1), High Inertial Movement Analysis (High-IMA), and Jumps were quantified using Catapult Openfield software during four distinct training periods of the year: 8-hour preseason, 20-hour preseason, non-conference, and conference game play. Weekly variations and acute to chronic workload ratios (ACWR) were also examined. Eleven subjects participated in daily external load monitoring during practice and games via Catapult's ClearSky T6 inertial measurement units (IMU). Averages, standard deviations, and confidence intervals were calculated for training period comparisons, and Cohen's d was calculated as a measure of effect size. Findings include normative values to provide context for the demands experienced across an entire season. PL was significantly higher during non-conference play than during any of the other three training periods (p < 0.05). Descriptive data enumerate percent change and ACRW variations throughout the season. These data can be used to describe the physical demands across a season and provide physical profile guidelines for coaches.

Increased Incidence of Upper Extremity Soft Tissue Injuries and Orthopaedic Surgeries in Patients with Eating Disorders

Background

Despite an established increased fracture risk in eating disorder patients, no studies, to our knowledge, have investigated the association between eating disorders and upper extremity soft tissue injury or surgery incidence. Given the association of eating disorders with nutritional deficiency and musculoskeletal sequelae, we hypothesized that patients with eating disorders would have an increased risk of soft tissue injury and surgery. The aim of this study was to elucidate this link and investigate if these incidences are increased in patients with eating disorders.

Methods

Cohorts of patients with anorexia ner-vosa or bulimia nervosa, identified using International Classification of Diseases (ICD) -9 and -10 codes, were identified in a large national claims database over 2010-2021. Control groups without these respective diagnoses were constructed, matched by age, sex, Charlson Comorbidity Index, record date, and geographical region. Upper extremity soft tissue injuries were identified using ICD-9 and -10 codes and surgeries using Current Procedural Terminology codes. Differences in incidence were analyzed using chi-square tests.

Results

Patients with anorexia and bulimia were significantly more likely to sustain a shoulder sprain (RR=1.77; RR=2.01, respectively), rotator cuff tear (RR=1.39; RR=1.62), elbow sprain (RR=1.85; RR=1.95), hand/wrist sprain (RR=1.73; RR=16.0), hand/wrist ligament rupture (RR=3.33; RR=1.85), any upper extremity sprain (RR=1.72; RR=1.85), or any upper extremity tendon rupture (RR=1.41; RR=1.65). Patients with bulimia were also more likely to sustain any upper extremity ligament rupture (RR=2.88). Patients with anorexia and bulimia were significantly more likely to undergo SLAP repair (RR=2.37; RR=2.03, respectively), rotator cuff repair (RR=1.77; RR=2.10), biceps tenodesis (RR=2.73; RR=2.58), any shoulder surgery (RR=2.02; RR=2.25), hand tendon repair (RR=2.09; RR=2.12), any hand surgery (RR=2.14; RR=2.22), or any hand/wrist surgery (RR=1.87; RR=2.06).

Conclusion

Eating disorders are associated with an increased incidence of numerous upper extremity soft tissue injuries and orthopaedic surgeries. Further work should be undertaken to elucidate the drivers of this increased risk. Level of Evidence: III.

Does the Time of Day Play a Role in the Acute Effect of p-Synephrine on Fat Oxidation Rate during Exercise in Women? A Randomized, Crossover and Double-Blind Study

p-Synephrine is deemed a safe and effective substance to increase fat utilization during exercise of low-to-moderate intensity in men but not in women. Additionally, the existence of a diurnal variation in substrate utilization has been documented during exercise with enhanced fat oxidation in the evening compared with early morning. However, it remains unknown whether there is an interaction between the effect of p-synephrine and the time of the day on fat oxidation during exercise. This study aimed to evaluate the effect of the acute ingestion of 3 milligram of p-synephrine per kilogram of body mass (mg/kg) on fat oxidation during exercise of increasing intensity when the exercise is performed in the morning vs. the evening. Using a randomized, double-blind, placebo-controlled experimental design, 16 healthy and active women performed four identical exercise trials after the ingestion of 3 mg/kg of p-synephrine and 3 mg/kg of a placebo (cellulose) both in the morning (8-10 am) and in the evening (5-7 pm). In the exercise trials, the substances were ingested 60 min before an incremental test on a cycle ergometer with 3 min stages at workloads from 30 to 80% of maximal oxygen uptake (VO₂max). Substrate oxidation rates were measured by indirect calorimetry. In each trial, the maximum rate of fat oxidation (MFO) and the intensity that elicited MFO (Fatmax) were measured. A two-way analysis of variance (time-of-the day × substance) was used to detect differences among the trials. With the placebo, MFO was 0.25 ± 0.11 g/min in the morning and 0.24 ± 0.07 g/min in the evening. With p-synephrine, MFO was 0.26 ± 0.09 g/min in the morning and 0.21 ± 0.07 g/min in the evening. There was no main effect of substance (p = 0.349), time of day (p = 0.186) and the substance × time of day (p = 0.365) on MFO. Additionally, Fatmax was reached at a similar exercise intensity with the placebo (41.33 ± 8.34% VO₂max in the morning and 44.38 ± 7.37% VO₂max in the evening) and with p-synephrine (43.33 ± 7.24% VO₂max in the morning and 45.00 ± 7.43% VO₂max in the evening), irrespective of the time of day with no main effect of substance (p = 0.633), time of day (p = 0.191), or interaction (p = 0.580). In summary, the acute intake of 3 mg/kg of p-synephrine before exercise did not increase MFO and Fatmax, independently of the time of day, in female athletes. This indicates that the time of day is not a factor explaining the lack of effectiveness of this substance to enhance fat oxidation during aerobic exercise in women.

Elite Female Athletes Demonstrate a Comparable Improvement in Midterm Patient-Reported Outcome Scores and Rate of Return to Sport Compared With Elite Male Athletes After Hip Arthroscopic Surgery: A Sex-Based Comparison in Professional and Collegiate Athletes

BACKGROUND

Few studies have compared outcomes, return to sport (RTS), and continuation of sport (CTS) after primary hip arthroscopic surgery between matched groups of male and female athletes with a minimum 5-year follow-up.

PURPOSE

(1) To report minimum 5-year patient-reported outcome (PRO) scores as well as RTS and CTS rates for elite female athletes undergoing hip arthroscopic surgery for femoroacetabular impingement syndrome (FAIS) and (2) to compare clinical results with those of a matched control group of elite male athletes.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

Data were prospectively collected and retrospectively reviewed for elite (collegiate or professional) female athletes who underwent primary hip arthroscopic surgery for FAIS between March 2009 and March 2016. Inclusion criteria were preoperative and minimum 5-year scores for the modified Harris Hip Score, Nonarthritic Hip Score, Hip Outcome Score-Sport Specific Subscale, and visual analog scale for pain. Exclusion criteria were Tönnis grade >1, hip dysplasia, previous ipsilateral hip surgery/conditions, and those unwilling to participate. Rates of achieving the minimal clinically important difference (MCID), Patient Acceptable Symptom State (PASS), and maximum outcome improvement satisfaction threshold (MOIST) were recorded in addition to RTS. CTS was also recorded and defined as athletes reporting continued sport activity at a minimum 5-year follow-up after initially reporting returning to sport. Elite female athletes were propensity matched in a 1:1 ratio to elite male athletes for comparison.

RESULTS

A total of 81 hips in elite female athletes that underwent primary hip arthroscopic surgery met the inclusion criteria, and follow-up was available for 65 hips (80.2%) at a mean of 67.6 ± 6.5 months, with a mean age of 24.3 ± 6.8 years. Female athletes demonstrated significant improvements in all recorded PRO scores; achieved the MCID, PASS, and MOIST at high rates; returned to sport at a rate of 80.4%; and continued sport at a rate of 97.1%. Female athletes demonstrated lower preoperative PRO scores compared with male athletes, but postoperative PRO scores; improvements in scores; rates of achieving the MCID, PASS, MOIST; and RTS and CTS rates were similar between female and male athletes.

CONCLUSION

Elite female athletes undergoing primary hip arthroscopic surgery for FAIS demonstrated favorable PRO scores and high RTS and CTS rates at a minimum 5-year follow-up. These results were comparable with those of a propensity-matched control group of elite male athletes.

Sport Specialization Classification and Injury Risk in Female Athletes

BACKGROUND

Description of possible detrimental effects of sport specialization specific to adolescent female athletes is limited in current literature with no consensus on sport specialization classification.

HYPOTHESIS

Specialized female athletes will have higher rates of injury, body image issues, and menstrual dysfunction, regardless of the specialization classification utilized.

STUDY DESIGN

Cross-sectional.

LEVEL OF EVIDENCE

Level 3.

METHODS

Retrospective data was obtained from questionnaires from female athletes in local high schools (n = 229; 13-18 years of age). The 3-point specialization scale was used to analyze differences in injury rates, body image issues, and menstrual dysfunction within low, moderate, and highly specialized athletes. When comparing accuracy of specialization scales in identifying high risk athletes, three peer-reviewed specialization classification scales were utilized-a 3-point scale, a 6-point scale, and a binary self-selection scale. Odds ratios (OR) and 95% confidence intervals (CI) were calculated for studied variables (a priori p ≤ 0.05).

RESULTS

Of 229 athletes surveyed, 219 (95.6%) completed the 3-point specialization classification questions and were included in the study. 91 athletes (41.6%) were categorized as low specialization (LS), 59 (26.9%) were moderately specialized (ModS), and 69 (31.5%) were highly specialized (HS). ModS athletes were more likely to have a history of stress fractures (SFx) compared to LS athletes (p = 0.02; OR 3.62; 95% CI 1.27-10.26). Compared to LS athletes, HS athletes were more likely to have injury history (p = 0.01; OR 2.93; 95% CI 1.38-6.24) and a history of concussion (p < 0.01; OR 5.00; 95% CI 1.86-13.42).

CONCLUSION

Among female high school athletes, higher levels of specialization are associated with greater risk of injuries overall, and greater risk of concussions and SFx. This study did not demonstrate significant associations between specialization and body image issues or menstrual dysfunction.

CLINICAL RELEVANCE

This study further strengthens the association between injury and sport specialization and suggests that combining specialization scales better improves risk stratification which overall aids in preventing athlete injury.

The Prevalence of Menstrual Cycle Disorders in Female Athletes from Different Sports Disciplines: A Rapid Review

The aim of this study was to rapidly review the literature on the prevalence of menstrual disorders in female athletes from different sports modalities. Articles were searched in the Web of Science and PubMed database in May 2022. A total of 1309 records were identified, and 48 studies were included in the final stage. The menstrual disorders described in the included studies were primary (in 33% of included studies) and secondary amenorrhea (in 73% of included studies) and oligomenorrhea (in 69% of included studies). The prevalence of menstrual disorders among the studies ranged from 0 to 61%. When data were pooled according to discipline (mean calculation), the highest prevalence of primary amenorrhea was found in rhythmic gymnastics (25%), soccer (20%) and swimming (19%); for secondary amenorrhea in cycling (56%), triathlon (40%) and rhythmic gymnastics (31%); and oligomenorrhea in boxing (55%), rhythmic gymnastics (44%) and artistic gymnastics (32%). Based on the results of this review, the study supports the literature of the higher prevalence of menstrual disorders in gymnastics and endurance disciplines. However, team sports modalities such as volleyball and soccer also presented a considerable percentage of menstrual disorders compared to the general population. It reinforces the importance of coaches and physicians paying attention to athletes' menstrual cycle as the occurrence of menstrual disorders can be associated with impairment on some health components.

Hamstring Injury Rehabilitation and Prevention in the Female Athlete

Hamstring injuries (HSIs) are common in female athletes and are associated with a lengthy recovery period and a high rate of reinjury. Currently, the majority of existing literature investigating HSI rehabilitation has been conducted using male participants. However, female athletes display intrinsic anatomical and biomechanical differences compared to males that influences the way this population experiences HSIs and HSI rehabilitation. HSI rehabilitation and injury prevention guidelines for female athletes must take these differences into account. Female athletes display anatomical differences such as increased anterior pelvic tilting, gluteus maximus weakness, an increased pelvic width-to-femoral length ratio, and an increased degree of femoral anteversion, all of which can predispose females to HSIs. Maneuvers designed to strengthen the gluteal musculature and transverse abdominis can overcome these risk factors. Females show increased joint laxity and a greater range of motion of hip flexion and internal rotation compared to males. Females have lower passive hamstring stiffness than males, therefore hamstring flexibility exercises may not be as necessary during rehabilitation for females as in the male athlete population. Female athletes may instead benefit from trunk stabilization exercises and agility training due to neuromuscular control deficits that arise from the maturation and growth of the female pelvis. Existing literature on hamstring injury prevention shows consistent use of the Nordic Hamstring Exercise and balance exercises may reduce the risk of sustaining an HSI in both males and females, though more studies are needed to ascertain the optimal regimen for injury prevention in the female athlete population specifically. The goal of this clinical commentary is to discuss sex-specific anatomic and biomechanical differences of the lumbar, pelvic, and hip regions with the aim of providing guidelines for rehabilitation and injury prevention of HSIs in female athletes.

Level of Evidence

5.

Epidemiology of female youth ice hockey injuries presenting to United States emergency departments from 2002 to 2019

BACKGROUND

This study documented injury types, rates and mechanisms for female youth ice hockey players reporting to US emergency departments to inform safety measures and sideline medical preparedness.

METHODS

The National Electronic Injury Surveillance System (NEISS) database was queried for ice hockey injuries (product code 1279) from 1 January 2002 to 31 December 2019. Incidence rate ratios (IRR) were calculated using OpenEpi and compared between age divisions. Spearman's rank correlation was utilized to evaluate the correlation between age and injury incidence. USA Hockey membership statistics were used to establish the population at risk and calculate incidence rates (IR).

RESULTS

An estimated 20,384 ice hockey injuries presented to participating United States emergency departments. The number of female youth ice hockey players increased significantly from 36,258 in 2002 to 65,072 in 2019 (p < 0.01). The most commonly injured body parts were the head (n = 5,519, IR = 62.1 [95%CI 54.3-70.0 per 10,000 athletes), trunk (n = 2,364, IR = 26.6 [95%CI 21.2-32.0] per 10,000 athletes), and wrist (n = 1,824, IR = 20.5 [95%CI 15.7-25.4] per 10,000 athletes). The most commonly reported mechanisms of injury were player-to-player collision (n = 4,746, IR = 53.4 [95%CI 46.4-60.5] per 10,000 athletes) and falls (n = 4,585, IR = 51.6 [95%CI 44.1-59.1] per 10,000 athletes). The most common diagnoses were traumatic brain injury (n = 5,333, IR = 60.0 [95%CI 52.3-67.8] per 10,000 athletes), contusion (n = 4,204, IR = 47.3 [95%CI 40.3-54.4] per 10,000 athletes) and strain/sprain (n = 3,601, IR = 40.5 [95%CI 34.1-47.0] per 10,000 athletes). A positive correlation was found between age and injury incidence, as well as increasing age and injuries from player-to-player collision and TBI's.

CONCLUSIONS

Though body checking is illegal at all levels of women's ice hockey, player-to-player collision prevailed as the leading mechanism on injury. Hopefully this study informs players, parents, coaches, trainers and clinicians about the impact of player-to-player collisions on overall injury burden in the older age divisions of youth female hockey.

Maximizing Recovery in the Postpartum Period: A Timeline for Rehabilitation from Pregnancy through Return to Sport

Increased participation and duration in sport has become commonplace for women with their involvement often including the transition to motherhood in the peak of their athletic careers. No rehabilitation models that assess the full spectrum of pregnancy to postpartum have been developed for women to assist in safe exercise progressions that reduce postpartum symptoms and optimize performance during the return to full activity. Referral to physical therapy both in the prenatal and postnatal period is currently not considered standard of care to reduce prevalence of symptoms such as musculoskeletal pain, diastasis recti, and pelvic floor dysfunction which may ultimately interfere with physical activity and performance. This commentary presents a timeline and suggested progression for exercise participation to improve awareness of the musculoskeletal changes that occur after labor and delivery. The concepts covered may increase the understanding of how to manage pregnant and postpartum athletes from a musculoskeletal perspective and serve as a starting point for establishing appropriate and guided rehabilitation for safe return to sport after childbirth.

Female Athlete Triad Risk Factors Are More Strongly Associated With Trabecular-Rich Versus Cortical-Rich Bone Stress Injuries in Collegiate Athletes

Background:

Bone stress injuries (BSIs) are common in athletes. Risk factors for BSI may differ by skeletal anatomy and relative contribution of trabecular-rich and cortical-rich bone.

Hypothesis:

We hypothesized that Female Athlete Triad (Triad) risk factors would be more strongly associated with BSIs sustained at trabecular-rich versus cortical-rich skeletal sites.

Study Design:

Cohort study; Level of evidence, 2.

Methods:

The study population comprised 321 female National Collegiate Athletic Association Division I athletes participating in 16 sports from 2008 to 2014. Triad risk factors and a Triad cumulative risk score were assessed using responses to preparticipation examination and dual energy x-ray absorptiometry to measure lumbar spine and whole-body bone mineral density (BMD). Sports-related BSIs were diagnosed by a physician and confirmed radiologically. Athletes were grouped into those sustaining a subsequent trabecular-rich BSI, a subsequent cortical-rich BSI, and those without a BSI. Data were analyzed with multinomial logistic regression adjusted for participation in cross-country running versus other sports.

Results:

A total of 19 participants sustained a cortical-rich BSI (6%) and 10 sustained a trabecular-rich BSI (3%) over the course of collegiate sports participation. The Triad cumulative risk score was significantly related to both trabecular-rich and cortical-rich BSI. However, lower BMD and weight were associated with significantly greater risk for trabecular-rich than cortical-rich BSIs. For every value lower than 1 SD, the odds ratios (95% CIs) for trabecular-rich versus cortical-rich BSI were 3.08 (1.25-7.56) for spine BMD; 2.38 (1.22-4.64) for whole-body BMD; and 5.26 (1.48-18.70) for weight. Taller height was a significantly better predictor of cortical-rich than trabecular-rich BSI.

Conclusion:

The Triad cumulative risk score was significantly associated with both trabecular-rich and cortical-rich BSI, but Triad-related risk factors appeared more strongly related to trabecular-rich BSI. In particular, low BMD and low weight were associated with significantly higher increases in the risk of trabecular-rich BSI than cortical-rich BSI. These findings suggest Triad risk factors are more common in athletes sustaining BSI in trabecular-rich than cortical-rich locations.

Season-Long Changes in the Body Composition Profiles of Competitive Female Rugby Union Players Assessed via Dual Energy X-Ray Absorptiometry

Background: Reference data for the body composition values of female athletes are limited to very few sports, with female Rugby Union players having mostly been omitted from such analyses.Methods: Using dual energy X-ray absorptiometry (DXA) scans, this study assessed the body composition profiles (body mass, bone mineral content; BMC, fat mass; FM, lean mass; LM, bone mineral density; BMD) of 15 competitive female Rugby Union players before and after the 2018/19 competitive season. Total competitive match-play minutes were also recorded for each player.Results: Body mass (73.7 ± 9.6 kg vs 74.9 ± 10.2 kg, p ≤ 0.05, d = 0.13) and BMC (3.2 ± 0.4 kg vs 3.3 ± 0.4 kg, p ≤ 0.05, d = 0.15) increased pre- to post-season for all players. Conversely, FM (21.0 ± 8.8 kg), LM (50.7 ± 3.9 kg), and BMD (1.31 ± 0.06 g·cm^-2) were similar between time-points (all p > .05). Accounting for position, body mass (r_partial(12) = 0.196), FM (r_partial(12) = -0.013), LM (r_partial(12) = 0.351), BMD (r_partial(12) = 0.168) and BMC (r_partial(12) = -0.204) showed no correlation (all p > .05) against match-play minutes.Conclusion: The demands of the competitive season influenced specific body composition indices (i.e., body mass, BMC) in female Rugby Union players; a finding which was unrelated to the number of minutes played in matches. While the causes of such differences remain unclear, practitioners should be cognizant of the body composition changes occurring throughout a female Rugby Union competitive season and, where necessary, consider modifying variables associated with adaptation and recovery accordingly.

Preseason Eccentric Strength Is Not Associated with Hamstring Strain Injury: A Prospective Study in Collegiate Athletes

INTRODUCTION

Established risk factors for hamstring strain injuries (HSI) include older age and prior HSI. However, these are nonmodifiable and have a limited role in injury prevention. Eccentric hamstring strength is a common component of HSI prevention programs, but its association with injury is less clear.

PURPOSE

This study aimed to determine if eccentric hamstring strength was prospectively associated with HSI among collegiate athletes, while controlling for sex, age, and prior HSI. We hypothesized that athletes with lower eccentric hamstring strength or greater between-limb strength asymmetry at preseason would have an increased risk of HSI.

METHODS

Hamstring eccentric strength measures, maximum total force ( FTotal ) and between-limb asymmetry in maximum force ( FAsym ), were measured at preseason on male and female athletes. HSIs were tracked over the subsequent 12 months. Generalized estimating equations were used to identify univariable and multivariable associations between athlete demographics, eccentric hamstring strength, and HSI risk.

RESULTS

Data for 326 athletes (85 female; 30 track, 43 basketball, 160 American football, 93 soccer) were included, and 64 HSIs were observed. Univariable associations between eccentric hamstring strength and subsequent HSI were nonsignificant ( FTotal : odds ratio [OR], 0.99 (95% confidence interval (CI), 0.93-1.05); P = 0.74; FAsym : OR, 1.35 (95% CI, 0.87-2.09); P = 0.23). No relationship between eccentric hamstring strength and HSI ( FAsym : OR, 1.32 (95% CI, 0.84-2.08); P = 0.23) was identified after adjusting for confounders including sex, age, and prior HSI.

CONCLUSIONS

No association between preseason eccentric hamstring strength and risk of subsequent HSI was identified after controlling for known risk factors and sex among collegiate athletes. Eccentric hamstring strengthening may continue to serve as a preventative approach to HSI, but it does not provide additional insight into HSI risk beyond factors such as age and prior HSI.