Training loads and microcycle periodisation in Italian Serie A youth soccer players.

Microcycles are fundamental structures for training prescription and load management, helping to optimise training effects and performance. This study quantified external and internal loads of Italian Serie A youth soccer players across competitive weeks and their periodisation within microcycles. Data were collected from 90 players belonging to four age groups (under-19, -17, -16, -15) across a season. Methods of monitoring external [duration and global navigation satellite systems (GNSS)] and internal load [heart rate (HR) and rating of perceived exertion (RPE)] were employed. Linear mixed models determined differences in training loads across age groups, training days and player positions. Under-19 and under-17 players trained five times per week, while younger players trained four times. Late-stage academy players (under-19 and -17) demonstrated higher weekly accumulated external and sRPE training load compared to their younger counterparts (p < 0.05 between groups). Weekly accumulated HR internal loads were higher in under-15 players (p < 0.05 between groups). Marked fluctuations of daily load were observed across microcycles in under-19 and under-17 groups (p < 0.05 between days). These findings highlight progressive increases in training load throughout the development pathway, with late-stage academy players training with higher frequency, volume and marked periodisation compared to younger players.

Talent development in female soccer: Developmental activities of professional players in England.

The activities soccer players engage in during their formative years are thought to significantly contribute to the acquisition of expert performance. Whilst this area has seen great interest in male players, there has been little research in females. The study examined developmental activities engaged in by professional female soccer players in England. 56 female soccer players that had either progressed to professional status in adulthood (professional), or did not (ex-academy), completed the Participant History Questionnaire. Professional players started engaging in soccer at an earlier age than their ex-academy counterparts, resulting in greater engagement in practice and play during childhood. During adolescence, professional players engaged in higher amounts of practice than ex-academy players. Engagement in competition and practice was rated as high in physical and cognitive effort by all, yet ex-academy players reported higher levels of physical effort during early adolescence, and cognitive effort during late adolescence. Findings provide an illustration of the talent pathways of professional female soccer players in England and may inform future talent development systems. Large interindividual variation in soccer-specific and other-sport activity data highlight the importance of further understanding the environments of individual soccer nations and their potential impact on the talent identification and development processes.

Intensity Gradients: A Novel Method for Interpreting External Loads in Football.

PURPOSE: Global navigation satellite system device-derived metrics are commonly represented by discrete zones with intensity often measured by standardizing volume to per-minute of activity duration. This approach is sensitive to imprecision in duration measurement and can lead to highly variable outcomes-transforming data from zones to a gradient may overcome this problem. The purpose of this study was to critically evaluate this approach for measuring team-sport activity demands. METHODS: Data were collected from 129 first-team and 73 academy matches from a Scottish Premiership football club. Gradients were calculated for velocity, acceleration, and deceleration zones, along with per-minute values for several commonly used metrics. Means and 95% CIs were calculated for playing level, as well as first-team positional groups. Within-subject coefficients of variation were also calculated for match level, position, and individual groups. RESULTS: The gradient approach showed consistency with per-minute metrics when measuring playing level and position groups. With coefficients of variation of 10.8% to 26.9%, the gradients demonstrated lower variability than most per-minute variables, which ranged from 10.7% to 84.5%. CONCLUSIONS: Gradients are a potentially useful way of describing intensity in team sports and compare favorably to existing intensity variables in their ability to distinguish between match types and position groups, providing evidence that gradient variables can be used to monitor match and training intensity in team sports.

Describing and Comparing Patient Factors Associated with Use of Parenteral Iron before and after Implementation of an Order Set for Parenteral Iron (DECODE IRON).

Background: In select clinical scenarios, IV administration of iron is suitable for management of iron deficiency anemia; however, for most patients, oral administration of iron is the mainstay of treatment. At the Red Deer Regional Hospital Centre, in Red Deer, Alberta, high utilization of IV iron has resulted in limited access to this medication for the treatment of ambulatory patients, as well as significant usage of health care resources. Objectives: The primary objective was to compare patient characteristics, specifically pretreatment laboratory test results and previous use of oral iron, among those receiving IV iron therapy in an ambulatory setting before and after implementation of an iron sucrose order set. For secondary objectives, the aforementioned groups were compared with regard to meeting the diagnostic criteria for iron deficiency anemia, with or without pretreatment oral iron or blood transfusion, and the dosing characteristics for IV iron. Methods: A retrospective electronic chart review was performed for ambulatory patients who received IV iron between January 1, 2020, and January 31, 2022. Results: A total of 436 unique treatment courses were included in the analysis. The following pretreatment laboratory results were observed before and after implementation of the iron sucrose order set: mean hemoglobin 105.8 (standard deviation [SD] 21.9) g/L versus 102.2 (SD 18.5) g/L; mean of mean corpuscular volume (MCV) 82.2 (SD 9.4) fL versus 79.2 (SD 8.9) fL; and median ferritin 7 (interquartile range [IQR] 4-12) µg/L versus 6 (IQR 4-11) µg/L. Only the difference in MCV values was statistically significant (p = 0.001). Conclusions: The implementation of an iron sucrose order set for ambulatory patients did not have a significant effect on pretreatment laboratory parameters among patients for whom IV iron was prescribed. Further stewardship initiatives could be beneficial in improving the appropriateness of IV iron use.

Contexte: Dans certains scénarios cliniques, l'administration de fer par voie intraveineuse (IV) convient à la prise en charge de l'anémie ferriprive; cependant, pour la plupart des patients, l'administration de fer par voie orale constitue le pilier du traitement. Au centre hospitalier régional Red Deer, à Red Deer, en Alberta, l'utilisation élevée du fer par IV a entraîné un accès limité à ce médicament pour le traitement des patients ambulatoires, ainsi qu'une utilisation importante des ressources de santé. Objectifs: L'objectif principal consistait à comparer les caractéristiques des patients, en particulier les résultats de tests de laboratoire avant traitement et l'utilisation antérieure de fer par voie orale, chez ceux recevant un traitement de fer par IV en milieu ambulatoire avant et après la mise en oeuvre d'un protocole de prescription de fer sucrosé. Les objectifs secondaires, quant à eux, étaient la comparaison des groupes susmentionnés en ce qui concerne la satisfaction des critères diagnostiques de l'anémie ferriprive, avec ou sans prétraitement de fer administré par voie orale ou par transfusion sanguine, ainsi que les caractéristiques posologiques du fer administré par IV. Méthodes: Un examen rétrospectif des dossiers électroniques a été réalisé pour les patients ambulatoires ayant reçu du fer par IV entre le 1er janvier 2020 et le 31 janvier 2022. Résultats: Au total, 436 traitements uniques ont été inclus dans l'analyse. Les résultats suivants de tests de laboratoire avant traitement ont été observés avant et après la mise en oeuvre du protocole de prescription de fer sucrosé: hémoglobine moyenne 105,8 g/L (écart type [ÉT] 21,9) contre 102,2 g/L (ÉT 18,5); moyenne du volume corpusculaire moyen (VCM) 82,2 fL (ÉT 9,4) contre 79,2 fL (ÉT 8,9); et ferritine médiane 7 µg/L (intervalle interquartile [IIQ] 4­12) contre 6 µg/L (IQR 4­11). La seule différence statistiquement significative concernait les valeurs VCM (p = 0,001). Conclusions: La mise en oeuvre d'un protocole de prescription de fer sucrosé pour les patients ambulatoires n'a pas eu d'effet significatif sur les paramètres biologiques avant traitement chez les patients pour lesquels du fer par IV a été prescrit. D'autres initiatives de gestion pourraient être bénéfiques pour améliorer la pertinence de l'utilisation du fer IV.

Comparisons and associations among anthropometric indices of first and second division and assistant soccer referees.

Introduction: Body composition is an important predictor of performance and a key component of health and physical fitness. Therefore, the purposes of this study were to compare soccer referees of the first and second divisions and field assistant referees from Iran and to analyze associations of a body shape index (ABSI), body adiposity index (BAI), abdominal volume index (AVI), body roundness index (BRI), conicity index (ConI), and body mass index (BMI) with body fat percentage (%BF). Methods: A total of 270 male soccer referees from the first (n = 124) and second (n = 72) divisions and assistant referees (n = 74) participated in this study. Skinfold thickness (measured at the chest, biceps, triceps, subscapular, abdominal, iliac crest, and front thigh), height, weight, hip circumference, and waist circumference were assessed to evaluate waist-to-height ratio (WHtR), %BF, and also ABSI, BRI, BAI, ConI, and AVI according to the ISAK protocol. Results: The main results indicated differences in WHR, WHtR, ABSI, BRI, AVI, ConI, and BF% with the assistant referees presenting higher values (p < 0.05). When considering the backward selection model, there were some associations with %BF in each group, specifically BMI, BAI, and ABSI in the first division; BMI, WHR, and ABSI in the second division; and BMI in the assistant referee group (all p < 0.05). Discussion: The present study did not confirm the hypothesis that the first-division referees presented better body composition-related variables than the second division or assistant referees. Instead, it showed that the assistant referees that participated in both divisions showed a tendency to higher values which suggests that the level of division is not a major factor when analyzing body composition.

Reliability and sensitivity to change of post-match physical performance measures in elite youth soccer players.

Introduction: To effectively monitor post-match changes in physical performance, valid, reliable and practical measures which are sensitive to change are required. This study aimed to quantify test-retest reliability and sensitivity to change of a range of physical performance measures recorded during an isometric posterior chain (IPC) lower-limb muscle test and a countermovement jump (CMJ) test. Methods: Eighteen Italian Serie A academy soccer players performed three IPC repetitions per limb and five CMJ trials in 4 testing sessions. Test-retest reliability was evaluated between two testing sessions seven days apart using typical error of measurement, coefficient of variation and intraclass correlation coefficient. Sensitivity to change was assessed on two additional testing sessions performed before and immediately after a soccer match through Hedges' g effect size (g) and comparisons to typical error. Results: Absolute reliability (coefficient of variations) ranged from 1.5 to 8.8%. IPC and CMJ measures demonstrated moderate to excellent relative reliability (intraclass correlation coefficients ranged from 0.70 to 0.98). A wide range of physical performance measures showed significant alterations post-match (p < 0.05; g: small to moderate). IPC peak force and torque, CMJ reactive strength index modified, CMJ eccentric forces (mean breaking force, mean deceleration force, peak force, force at zero velocity) and CMJ mean power measures had post-match changes greater than their typical variation, demonstrating acceptable sensitivity in detecting performance changes at post-match. Discussion: IPC peak force and torque, CMJ reactive strength index modified, CMJ eccentric phase forces and CMJ mean power were found to be both reliable and sensitive to change, and thus may be appropriate for monitoring post-match neuromuscular performance in youth soccer population.

The effect of two sessions of combined jump and sprint training per week on fitness parameters in soccer players. A randomized controlled trial.

This study aimed to investigate the effect of a combined jump and sprint training program, two sessions a week for 6 weeks, on sprinting, change of directions (COD) and jumping performance in semi-professional soccer players. Twenty soccer players were enrolled in this randomized controlled trial (age 20 ± 2 years, body mass 74.3 ± 5.9 kg). Players were randomized into two groups such as training group (TG, n = 10 players) or control group (CG, n = 10 players). Physical tests were performed before and after 6 weeks of training such as sprint 10 m, sprint 30 m, 505-COD test and standing long jump (LJ). The two groups performed the same training except for the combined jump and sprint training performed twice a week by TG. After 6 weeks of training, between-group analysis reported statistical difference in favor of the TG in sprint 10 m (p = 0.015, η2 = 0.295, large), sprint 30 m (p < 0.001, η2 = 0.599, large), in 505-COD (p = 0.026, η2 = 0.154, large), and LJ (p = 0.025, η2 = 0.027, small). These data indicate that combined sprint and jump training, when performed twice a week, for the duration of 6 weeks, in addition to the regular team training, can improve specific physical performance in male soccer players. This study has shown that a volume increment of 10% after 3 weeks of training can be a suitable training dose progression and that a combination of 64-70 jumps and 675-738 m of sprinting training per session can yield benefits in sprint, COD and jump performance.

The Genetic Association with Athlete Status, Physical Performance, and Injury Risk in Soccer.

The aim of this review was to critically appraise the literature concerning the genetic association with athlete status, physical performance, and injury risk in soccer. The objectives were to provide guidance on which genetic markers could potentially be used as part of future practice in soccer and to provide direction for future research in this area. The most compelling evidence identified six genetic polymorphisms to be associated with soccer athlete status (ACE I/D; ACTN3 rs1815739; AGT rs699; MCT1 rs1049434; NOS3 rs2070744; PPARA rs4253778), six with physical performance (ACTN3 rs1815739; AMPD1 rs17602729; BDNF rs6265; COL2A1 rs2070739; COL5A1 rs12722; NOS3 rs2070744), and seven with injury risk (ACTN3 rs1815739; CCL2 rs2857656; COL1A1 rs1800012; COL5A1 rs12722; EMILIN1 rs2289360; IL6 rs1800795; MMP3 rs679620). As well as replication by independent groups, large-scale genome-wide association studies are required to identify new genetic markers. Future research should also investigate the physiological mechanisms associating these polymorphisms with specific phenotypes. Further, researchers should investigate the above associations in female and non-Caucasian soccer players, as almost all published studies have recruited male participants of European ancestry. Only after robust, independently replicated genetic data have been generated, can genetic testing be considered an additional tool to potentially inform future practice in soccer.

Rationale and Practical Recommendations for Testing Protocols in Female Soccer: A Narrative Review.

ABSTRACT: Beato, M, Datson, N, Anderson, L, Brownlee, T, Coates, A, and Hulton, A. Rationale and practical recommendations for testing protocols in female soccer: A narrative review. J Strength Cond Res 37(9): 1912-1922, 2023-The aim of this narrative review is to evaluate the presented literature on tests (aerobic, speed, changes of direction [COD], strength, power, jump, and anthropometry) of the varied components of female soccer and to draw attention to the most suitable protocols to allow practitioners to accurately track players' fitness status. The 2 most common field tests used to assess aerobic fitness are the Yo-Yo intermittent test (level 1 and level 2) and the 30-15 intermittent fitness test because of an ability to measure multiple players at once with a soccer-specific intermittent profile. The sprinting performance can be assessed on distances of <30 m; however, longer distances (e.g., 40 m) allow for achieving peak speed (flying sprint test), which can be assessed using global navigation satellite system. Changes-of-direction capacity has been found to be an important component of players testing and training programs, although there is no "gold standard" to assess COD or repeated sprint ability performance in female players. Lower-limb power can be assessed using jump tests that can use force platforms, jump mats, and optoelectronic devices, while maintaining a good reliability. Several in-direct tests are currently available for assessing anthropometry parameters, such as skinfold thickness, hydrodensitometry, and ultrasound. However, dual-energy x-ray absorptiometry is the most valid and reliable method for assessing body composition in team sport athletes, with the addition of bone health that is a key measure in female athletes. In conclusion, the evidence reported in this review will be able to aid practitioners, coaches, and researchers to decide which tests meet the requirements of their environment.

Effect of High-Intensity vs. Moderate-Intensity Resistance Training on Strength, Power, and Muscle Soreness in Male Academy Soccer Players.

ABSTRACT: McQuilliam, SJ, Clark, DR, Erskine, RM, and Brownlee, TE. The effect of high vs. moderate-intensity resistance training on strength, power and muscle soreness in male academy soccer players. J Strength Cond Res 37(6): 1250-1258, 2023-The aims of this study were to investigate the impact of high-intensity, low-volume (HRT) vs . moderate-intensity, and high-volume resistance training (MRT) vs . soccer training only (control group [CON]) on changes in strength, power, and speed and to compare delayed onset muscle soreness (DOMS) between groups in male academy soccer players (ASP). Twenty-two ASP (age: 18 ± 1 years) were assigned to HRT ( n = 8), MRT ( n = 7), or CON ( n = 7). High-intensity resistance training completed 2 sets of 4 repetitions parallel back squat (PBS) repetitions at 90% 1 repetition maximum (1RM), while MRT performed 3 sets of 8 repetitions PBS repetitions at 80% 1RM, both once a week for 6 weeks in-season, alongside regular soccer training. All groups completed the following pretraining and posttraining assessments: 3RM PBS, bilateral vertical and horizontal countermovement jumps (CMJ), squat jump (SJ), and 30-m sprint. Delayed onset muscle soreness was assessed using a visual analog scale throughout training. High-intensity resistance training and MRT experienced similar increases compared with CON in absolute PBS 3RM ( p < 0.001), SJ height ( p = 0.001), and CMJ height ( p = 0.008) after training. There was a greater increase in PBS 3RM relative to body mass after HRT than MRT and CON ( p = 0.001) and horizontal CMJ distance improved in HRT but not in MRT or CON ( p = 0.011). There was no change in 10-m, 20-m, or 30-m sprint performance in any group. High-intensity resistance training volume was 58 ± 15% lower than that of MRT ( p < 0.001), and DOMS measured throughout training did not differ between groups ( p = 0.487). These findings suggest that 1 HRT session a week may be an efficient method for improving strength and power in ASP in-season with minimal DOMS.

Determining the definition and components of successful soccer referee performance.

There has been little work examining the intricacies of what makes a soccer referee successful. The aim of this study was to determine what the definition of a successful referee performance is and what are the characteristics of a successful referee from a broad range of stakeholders in Major League Soccer (MLS) and the Professional Referees Organisation (PRO). The study used Delphi methodology to ask 6 MLS General Managers, 2 MLS Coaches,1 MLS League Officer, 4 PRO Referees and 10 PRO Assistant Referees, 8 PRO Staff and 5 PRO Assessors, and 2 PRO2 Referees two questions: 1. Their definition of a successful referee performance. 2. Their opinion on the characteristics of a successful referee. The result was a 7-point definition of a successful referee performance and 26 characteristics of a successful referee. There were ten characteristics that overlapped with previous work examining successful referees. This study was able to develop a definition of a successful referee performance and determine the characteristics of a successful referee.

Perception and application of flywheel training by professional soccer practitioners.

Growing evidence supports use of eccentric methods for strength development and injury prevention within elite soccer, yet uncertainty remains regarding practitioners' application of flywheel (isoinertial) methods. The aims of this study were to investigate how the flywheel training literature is perceived and applied by elite soccer practitioners, highlight gaps in knowledge and develop industry-relevant research questions. Fifty-one practitioners completed an electronic questionnaire. Fourteen Likert scale statements were grouped into topics: strength and performance; post-activation performance enhancement and methodological considerations; chronic strength; chronic performance; injury prevention. Three general questions followed, allowing more detail about flywheel training application. A Majority of the participants reported ≥ 2 years' experience of programming flywheel training. Nearly all participants agreed that familiarisation is needed. Practitioners agree that flywheel training can improve sport performance, strength and likelihood of non-contact injury outcomes. Most practitioners prescribe 2 weekly sessions during pre- and in-season periods. Flywheel sessions mostly consist of squats but a variety of exercises (lunge, hip hinge, and open kinetic chain) are also frequently included. Practitioners are mostly unsure about differences between flywheel and traditional resistance training equipment and outcomes, practicality of flywheel equipment, and evidence-based guidelines. The investigation provides valuable insight into the perspectives and application of flywheel training within elite soccer, highlighting its perceived efficacy for strength and injury prevention.

Mind the gap! A survey comparing current strength training methods used in men's versus women's first team and academy soccer.

PURPOSE: Much less is known about strength and conditioning (S&C) practice in women's versus men's soccer. The aim of this study was to compare S&C practice between coaches working in men's or women's soccer, at first team or academy level, worldwide. METHODS: A total of 170 participants, who were involved with S&C support at their soccer club (in Europe, USA and South America, within men's or women's first team or academy settings) completed a comprehensive online survey, designed to evaluate (i) their academic qualifications and S&C coaching experience; and their preferred methods for (ii) physical testing; (iii) strength and power development; (iv) plyometric training; (v) speed development; and (vi) periodization. RESULTS: Women's academies had fewer weekly in-season S&C sessions than men's academies (1.6±0.6 vs. 2.3±0.9, p=0.005). Relatively, fewer women's academy S&C coaches (6%) used Olympic weightlifting movements than men's academy S&C coaches (32%, p=0.030). Relatively, more women's academy coaches (47%) used the Nordic hamstring exercise (NHE) compared to men's academy coaches (15%, p=0.006), but relatively more women's vs. men's first team coaches (61% vs. 38%, p=0.028) and women's vs. men's academy (61% vs. 38% coaches, p=0.049) utilised rating of perceived exertion-based load prescriptions. CONCLUSION: Notable differences in S&C practice exist between coaches of men's and women's soccer squads, particularly at academy level. Fewer weekly S&C sessions in women academy players may have implications for physical development, while the greater use of subjective load prescriptions in both academy and first team women's squads may lead to sub-optimal performance gains.

Recovery following the extra-time period of soccer: practitioner perspectives and applied practices.

Research has demonstrated that the extra-time (ET) period of soccer negatively impacts recovery. However, it is not known to what extent recovery practices are being adapted by practitioners following ET and where gaps exist between research and practice. Therefore, this study explored soccer practitioner perceptions of recovery practices following ET matches. A total of 72 practitioners from across different levels of soccer and several countries completed a bespoke online survey. Inductive content analysis of the responses identified five higher-order themes: 'conditioning', 'player monitoring', 'recovery practices', 'training', and 'future research directions'. Mixed responses were received in relation to whether practitioners condition players in preparation for ET, though 72% allowed players to return to training based on fatigue markers following this additional 30-min period. Sixty-three (88%) practitioners believed that ET delays the time-course of recovery, with 82% highlighting that practices should be adapted following ET compared with a typical 90-min match. Forty-nine practitioners (68%) reduce training loads and intensities for up to 48 hr post ET matches, though training mostly recommences as 'normal' at 72 hr. Sixty-three (88%) practitioners believed that more research should be conducted on recovery following ET, with 'tracking players physiological and physical responses', 'nutritional interventions to accelerate recovery' and 'changes in acute injury-risk' being the three areas of research that practitioners ranked as most important. These data suggest practitioners and coaches adjust recovery practices following ET matches compared to 90 min. Further research on the efficacy of recovery strategies following ET matches is required to inform applied practice.

The Effect of a Single Session of Plyometric Training Per Week on Fitness Parameters in Professional Female Soccer Players: A Randomized Controlled Trial.

ABSTRACT: Nonnato, A, Hulton, AT, Brownlee, TE, and Beato, M. The effect of a single session of plyometric training per week on fitness parameters in professional female soccer players. A randomized controlled trial. J Strength Cond Res 36(4): 1046-1052, 2022-As the interest and popularity of female soccer has increased over the last few decades, there still lacks research conducted with the elite population, specifically ecological training interventions during the competitive season. Therefore, the aim of this study was to compare the effectiveness of 12 weeks (undertaken once a week) of plyometric (PLY) training on physical performance in professional female soccer players during the season. Using a randomized controlled trial design, 16 players were included in the current study (mean ± SD; age 23 ± 4 years, weight 60.3 ± 4.9 kg, height 167 ± 3.7 cm) and randomized in PLY (n = 8) and Control groups (CON, n = 8), respectively. Squat jump (SJ), counter movement jump (CMJ), long jump (LJ), single-leg triple jump distance test (triple jump test), changes of direction 505 test (505-COD), and sprint 10 and 30 m were performed before and after 12 weeks of PLY training. Significant within-group differences were found in triple jump test dominant (p = 0.031, effect size [ES] = moderate) and nondominant limb (p = 0.021, ES = moderate) and sprint 10 m (p = 0.05, ES = large), whereas the CON did not report any positive variation. However, neither group reported significant variation in SJ, CMJ, LJ, 505-COD, and sprint 30 m (underlining the difficulties in obtain meaningful variation in season). These findings have strong practical applications because this study showed for the first time that a single session a week of plyometric training can significantly increase sport-specific fitness parameters in professional female soccer players during the season.

The genetic association with injury risk in male academy soccer players depends on maturity status.

It is currently unknown if injury risk is associated with genetic variation in academy soccer players (ASP). We investigated whether nine candidate single nucleotide polymorphisms were associated (individually and in combination) with injury in ASP at different stages of maturation. Saliva samples and one season's injury records were collected from 402 Caucasian male ASP from England, Spain, Uruguay, and Brazil, whose maturity status was defined as pre- or post-peak height velocity (PHV). Pre-PHV COL5A1 rs12722 CC homozygotes had relatively higher prevalence of any musculoskeletal soft tissue (22.4% vs. 3.0%, p = 0.018) and ligament (18.8% vs. 11.8%, p = 0.029) injury than T-allele carriers, while VEGFA rs2010963 CC homozygotes had greater risk of ligament/tendon injury than G-allele carriers. Post-PHV IL6 rs1800795 CC homozygotes had a relatively higher prevalence of any (67.6% vs. 40.6%, p = 0.003) and muscle (38.2% vs. 19.2%, p = 0.013) injuries than G-allele carriers. Relatively more post-PHV EMILIN1 rs2289360 CC homozygotes suffered any injury than CT and TT genotypes (56.4% vs. 40.3% and 32.8%, p = 0.007), while the "protective" EMILIN1 TT genotype was more frequent in post- than pre-PHV ASP (22.3 vs. 10.0%, p = 0.008). Regardless of maturity status, T-alleles of ACTN3 rs1815739 and EMILIN1 rs2289360 were associated with greater absence following ankle injury, while the MMP3 rs679620 T-allele and MYLK rs28497577 GT genotype were associated with greater absence following knee injury. The combination of injury-associated genotypes was greater in injured vs. non-injured ASP. This study is the first to demonstrate that a genetic association exists with injury prevalence in ASP, which differs according to maturity status.

Come Back Skinfolds, All Is Forgiven: A Narrative Review of the Efficacy of Common Body Composition Methods in Applied Sports Practice.

Whilst the assessment of body composition is routine practice in sport, there remains considerable debate on the best tools available, with the chosen technique often based upon convenience rather than understanding the method and its limitations. The aim of this manuscript was threefold: (1) provide an overview of the common methodologies used within sport to measure body composition, specifically hydro-densitometry, air displacement plethysmography, bioelectrical impedance analysis and spectroscopy, ultra-sound, three-dimensional scanning, dual-energy X-ray absorptiometry (DXA) and skinfold thickness; (2) compare the efficacy of what are widely believed to be the most accurate (DXA) and practical (skinfold thickness) assessment tools and (3) provide a framework to help select the most appropriate assessment in applied sports practice including insights from the authors' experiences working in elite sport. Traditionally, skinfold thickness has been the most popular method of body composition but the use of DXA has increased in recent years, with a wide held belief that it is the criterion standard. When bone mineral content needs to be assessed, and/or when it is necessary to take limb-specific estimations of fat and fat-free mass, then DXA appears to be the preferred method, although it is crucial to be aware of the logistical constraints required to produce reliable data, including controlling food intake, prior exercise and hydration status. However, given the need for simplicity and after considering the evidence across all assessment methods, skinfolds appear to be the least affected by day-to-day variability, leading to the conclusion 'come back skinfolds, all is forgiven'.

Patient Factors Associated with Prescribing of Iron for IV Administration: A Descriptive Study.

BACKGROUND: IV administration of iron is appropriate for the treatment of iron deficiency anemia (IDA) when orally administered iron has not been effective, tolerated, or clinically appropriate. In Calgary, Alberta, high levels of IV iron utilization required review, because of significant health care resource utilization, high cost, and reduced accessibility. OBJECTIVES: The primary objective was to describe the population of adult patients in Calgary with estimated glomerular filtration rate greater than or equal to 30 mL/min/1.73 m2 for whom IV iron was dispensed from acute care facilities, in terms of pretreatment laboratory data, previous use of oral iron, and treatment location, as well as to characterize dose and product selection for IV iron. The secondary objective was to determine the proportion of inpatients whose treatment was in alignment with the Toward Optimized Practice clinical practice guideline for IDA. METHODS: A retrospective review of electronic charts was used to obtain data about patients with a first dose of IV iron dispensed in Calgary hospitals between March 1 and December 31, 2018. The data were analyzed descriptively. RESULTS: A total of 1352 patients met the inclusion criteria. These patients received a total of 3532 doses of IV iron, 97.1% of which were iron sucrose, at a median of 300 mg per infusion. Laboratory indices assessed before the first infusion were hemoglobin (mean 92, standard deviation [SD] 19.6 g/L), mean corpuscular volume (mean 81 [SD 10.3] fL), and ferritin (median 18 [interquartile range 9-48] µg/L). Among the included patients, 233 (17.2%) had oral iron dispensed within 90 days before their first IV dose of iron. Only 146 (20.1%) of the 726 inpatients had treatment that was in alignment with the Toward Optimized Practice IDA guideline. CONCLUSIONS: There was substantial variation in baseline hemoglobin, mean corpuscular volume, and ferritin, and in the use of oral iron before initiation of IV iron treatment. Provision of educational tools and stewardship initiatives may help in ensuring alignment of iron prescribing with current guidelines.

CONTEXTE: L'administration de fer par intraveineuse (IV) convient au traitement de l'anémie ferriprive lorsque son administration par voie orale n'a pas été efficace, tolérée ou appropriée d'un point de vue clinique. À Calgary (Alberta), il a fallu réviser les quantités de fer administrées par IV en raison de la mobilisation importante des ressources de soins de santé et des coûts élevés que cela exigeait ainsi que de l'accessibilité réduite au produit. OBJECTIFS: L'objectif principal consistait à décrire la population de patients adultes, dont le taux estimé de filtration glomérulaire était supérieur ou égal à 30 mL/min/1,73 m2 et à qui on administrait du fer par IV dans des installations de soins intensifs de Calgary. La description devait se faire en termes de données de laboratoire préalables au traitement, d'administration antérieure de fer par voie orale et de lieu du traitement; il s'agissait aussi de décrire la dose et la sélection du produit pour l'administration de fer par IV. L'objectif secondaire consistait à déterminer la proportion de patients hospitalisés, dont le traitement s'alignait sur les directives de pratique clinique Toward Optimized Practice relatives à l'anémie ferriprive. MÉTHODES: Un examen rétrospectif des tableaux électroniques a permis d'obtenir des données sur les patients, ayant reçu une première dose de fer par IV dans les hôpitaux de Calgary, entre le 1er mars et le 31 décembre 2018. Les données ont fait l'objet d'une analyse descriptive. RÉSULTATS: Au total, 1352 patients répondaient au critère d'inclusion. Ils ont reçu 3532 doses de fer par IV, dont 97,1 % de saccharose de fer à raison d'une médiane de 300 mg par perfusion. Les indices de laboratoire évalués avant la première perfusion concernaient l'hémoglobine (moyenne 92, écart-type [ET] 19,6 g/L), le volume corpusculaire moyen (moyenne 81 [ET 10,3] fL) et la ferritine (moyenne 18 [écart interquartile 9­48] µg/L). Parmi les patients de l'étude, 233 (17,2 %) avaient reçu du fer par voie orale 90 jours avant la première dose de fer administrée par IV. Seuls 146 (20,1 %) des 726 patients hospitalisés avaient reçu un traitement conforme aux directives de pratique clinique Toward Optimized Practice relatives à l'anémie ferriprive. CONCLUSIONS: On a constaté une variation importante de l'hémoglobine de base, du volume corpusculaire moyen et de la ferritine, ainsi que de l'utilisation du fer par voie orale avant le début du traitement par IV. Des outils pédagogiques et des initiatives de gestion pourraient aider à assurer l'alignement de la prescription de fer sur les directives actuelles.

Feedback of GPS training data within professional English soccer: a comparison of decision making and perceptions between coaches, players and performance staff.

Purpose: The aim of the study was to examine the perceptions of training data feedback from key stakeholders within the coaching process of professional soccer clubs. A survey assessed the importance of training data towards reflection and decision-making, potential barriers and player preferences.Methods: A total of 176 participants comprising coaches, players and performance staff completed the survey.Results: The training data coaches most commonly identified as wanting to see to support reflection was 'high-intensity' actions and variables recognised by the coach as 'work rate/intensity'. All stake- holders reported training data as at least somewhat important in guiding their coaches' practices, with lack of a common goal and high volumes of information being the main barriers to effective feedback of training data. Players deemed feedback as positive to change their behaviour, with total distance, high-speed running and sprint distances as the information they would most like to see. It would be likely to be looked at via message or pinned up in the changing room.Conclusion: Training data are seen as an impactful and effective tool for use by all key stakeholders. Despite this, its use can be optimised by increasing opportunities for informal reflection, using less information, and improving communication of data.

The prevalence of disordered eating in elite male and female soccer players.

PURPOSE: To examine the prevalence of disordered eating (DE) in elite male and female soccer players and the influence of perfectionism. METHODS: Using a cross-sectional design, elite male (n = 137) and female (n = 70) soccer players and non-athlete controls (n = 179) completed the clinical perfectionism questionnaire (CPQ-12) and the eating attitudes test (EAT-26) to assess perfectionism and DE risk, respectively. RESULTS: Male soccer players had higher EAT-26 scores than controls (10.4 ± 9.9 vs. 6.8 ± 6.7; P = 0.001), but there were no differences in the prevalence of clinical levels of DE (EAT-26 score ≥ 20) (15 vs. 5%, respectively; X2 = 0.079) The proportion of females with DE risk was higher in controls [EAT-26: 13.9 ± 11.6 (25% of population)] than female players [EAT-26: 10.0 ± 9.0% (11% of population)] (X2 = 0.001). With linear regression, perfectionism explained 20% of the variation in DE risk in males (P = 0.001); in females, athletic status (player vs. control) and perfectionism were significant predictors of DE risk, explaining 21% of the variation (P = 0.001). Male reserve team players had higher EAT-26 (+ 3.5) and perfectionism (+ 2.7) scores than first-team players (P < 0.05). There were no differences in the prevalence of DE risk between the male and female soccer players (X2 = 0.595). CONCLUSIONS: The prevalence of DE risk was not different in elite male and female soccer players; in fact, the prevalence was greatest in non-athlete female controls. Perfectionism is a significant predictor of DE risk in males and females. LEVEL OF EVIDENCE: III, case-control study.