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The authors acknowledge that Liz Ellis did not co-author this article and was erroneously listed as co-author. Editor’s note: COPE flowchart Changes in authorship d) (“Request for removal of author after publication”) was followed.

Background: Bacterial resistance to antibiotics is considered as natural phenomenon that occurs over the time due to genetic changes. Bacterial resistance to antibiotics is significantly increasing in the UAE. Self-medication with antibiotics has been identified as a major factor for the development of antibiotic resistance, which is significantly increasing in the UAE. Objectives: The purpose of this study was to explore the factors that contribute to the use of antibiotics without prescriptions among first year healthcare university students in UAE. Methods: Based on the findings of an earlier survey study, a qualitative interview study was designed to explore common themes related to student’s knowledge, awareness, attitude, views, and perceptions. Data were analyzed thematically for the identification of themes and subthemes within the data through the use of coding. Results: The interview study identified four main themes with multiple subthemes related to the use of antibiotics without a physician’s prescription by first-year healthcare students. The thematic analysis of the interviews revealed four main themes; medication habits and practices; reasons for self-medication; access to antibiotics without a prescription and gaps in students’ knowledge regarding antibiotic resistance Conclusions: Healthcare students in UAE are influenced by several factors including parents and friends influence, successful previous experience and investment of time and money to visit a physician. Our sample of healthcare students has a misconception about the use of antibiotics. The current interview study identified six new reasons for using antibiotics without prescriptions as compared to our earlier survey study. There is a need of multifaceted strategies to decrease unnecessary antibiotic use in our population sample.

Within-day and between-day reproducibility of supine and tilt baroreflex sensitivity were investigated utilising sequence and spectral indices in 46 healthy adult males employing 3 repeat measures; baseline, + 60 min and + 24 h. Reproducibility was assessed via the 95 % limits of agreement and by the technical error of the measurement. For spectral parameters, the limits of agreement indicated same day was marginally better than between-day reproducibility. For sequence parameters, between-day had marginally better agreement than same-day reproducibility. Tilt markedly improved reproducibility across all outcome measures. Precision expressed by the technical error of the measurement for all spectral outcomes was good in both supine and tilt baroreflex sensitivity (< 6%). Precision was lower, but acceptable, for sequence baroreflex sensitivity outcomes in both positions (< 11 %). Baroreflex sensitivity transfer gain provided the best agreement and reproducibility during supine and tilt conditions. These findings suggest time and spectral techniques may be employed to assess within-day and between-day baroreflex sensitivity changes in healthy individuals. The inclusion of a tilt manoeuvre may improve the reproducibility of the outcome measure, which may aid in the detection of modest baroreflex sensitivity changes in studies employing limited sample sizes. [ABSTRACT FROM AUTHOR]

Objective: (1) to analyse the accumulative effects of a 12-week active stretching program on hip flexion passive range of motion (HF-PROM), and (2) to compare whether participants with different PROM baseline scores (normal and limited hamstring flexibility) respond in the same way to stretching. Design: Repeated measures design. Setting: Controlled laboratory environment. Participants: 138 males were categorized according to hamstring flexibility in the unilateral passive straight-leg raise test (PSLR) and assigned to one of two groups: normal hamstring flexibility (⩾80°) or limited hamstring flexibility (<80°). In each group, participants were randomly distributed into one of two treatment subgroups: (a) control or (b) active stretching. The active stretching subgroups performed 12 weeks of flexibility training, the control subgroups did not stretch. Main Outcome Measures: HF-PROM was determined through the PSLR test. Results: Both stretching subgroups significantly improved (p < 0.01) their HF-PROM from baseline. The control subgroups did not. Conclusions: 12 weeks of an active stretching program performed 3 days per week with a daily stretch dose of 180 s improved HF-PROM in both populations (normal and limited hamstring flexibility). The stretching programwas equally effective in terms of absolute improvement values for males with normal and limited hamstring flexibility. [ABSTRACT FROM AUTHOR]

The main purpose of this study was to determine the absolute reliability of conventional (H/QCONV) and functional (H/QFUNC) hamstring to quadriceps strength imbalance ratios calculated using peak torque values, 3 different joint angle-specific torque values (10°, 20° and 30° of knee flexion) and 4 different joint ROM-specific average torque values (0-10°, 11-20°, 21-30° and 0.30° of knee flexion) adopting a prone position in recreational athletes. A total of 50 recreational athletes completed the study. H/QCONV and H/QFUNC ratios were recorded at 3 different angular velocities (60, 180 and 240°/s) on 3 different occasions with a 72-96 h rest interval between consecutive testing sessions. Absolute reliability was examined through typical percentage error (CVTE), percentage change in the mean (CM) and intraclass correlations (ICC) as well as their respective confidence limits. H/QCONV and H/QFUNC ratios calculated using peak torque values showed moderate reliability values, with CM scores lower than 2.5 %, CVTE values ranging from 16 to 20 % and ICC values ranging from 0.3 to 0.7. However, poor absolute reliability scores were shown for H/QCONV and H/QFUNC ratios calculated using joint angle-specific torque values and joint ROM-specific average torque values, especially for H/QFUNC ratios (CM: 1-23 %; CVTE : 22-94 %; ICC: 0.1-0.7). Therefore, the present study suggests that the CVTE values reported for H/QCONV and H/QFUNC (≈ 18 %) calculated using peak torque values may be sensitive enough to detect large changes usually observed after rehabilitation programmes but not acceptable to examine the effect of preventitive training programmes in healthy individuals. The clinical reliability of hamstring to quadriceps strength ratios calculated using joint angle-specific torque values and joint ROM-specific average torque values are questioned and should be re-evaluated in future research studies. [ABSTRACT FROM AUTHOR]

Abstract: Objective: 1) to examine the test-retest reproducibility and criterion-related validity of the sit and reach test (SRT) and the toe touch test (TT) for estimating hamstring flexibility measured through the passive straight leg raise test (PSLR); and 2) to determine whether the SRT cut-off scores may be used for the TT test to identify participants in this sample of young healthy adults as having short hamstring flexibility. Design: Test-retest design. Setting: Controlled laboratory environment. Participants: 243 active recreationally young adults. Main outcome measures: Participants performed the SRT, the TT test and PSLR twice in a randomized order with a 4-week interval between trials. Reproducibility was examined using typical percentage error (coefficient of variation [CV]) and intraclass correlation coefficient (ICC) as well as their respective confidence limits. Regression and Kappa correlation statistical analyses were performed to study the association of the SRT and TT test with the PSLR test and the 95% limits of agreement (LoA) between SRT and TT test were calculated to explore differences in the mean differences between these measurements. Results: The finding showed acceptable reproducibility measures for SRT (8.74% CV; 0.92 ICC), TT test (9.86% CV; 0.89 ICC) and PSLR (5.46% CV; 0.85 ICC). The SRT (R 2 = 0.63) and TT test (R 2 = 0.49) were significantly associated with PSLR. The 95% LoA between SRT and TT test reported systematic bias (2.84 cm) and wide 95% random error (±9.72 cm). Conclusions: Reproducibility of SRT, TT test and PSLR is acceptable and the criterion-related validity of SRT and TT test is moderate. Furthermore, the SRT cut-off scores should not be used for TT test for the detection of short hamstring muscles. [Copyright &y& Elsevier]

Abstract: Objective: To examine the criterion related validity of the sit-and-reach test (SR), toe touch test (TT), modified sit-and-reach test (MSR) and back-saver sit-and-reach test (BSSR) for estimating hamstring flexibility measured through the passive straight leg raise test (PSLR) in professional futsal players. Design: Correlation laboratory study. Setting: Controlled laboratory environment. Participants: One hundred and three futsal players (55 males age 26 ± 4 years, 48 females age 23 ± 5 years). Main outcome measures: Two trials of SR, TT, MSR, BSSR (left and right) and PSLR right and left (hamstring criterion measure) in a randomized order. Results: Regression analysis was performed to examine the association of SR, TT, MSR and BSSR with PSLR in both males and females separately. In males, only MSR test had moderate association criterion with PSLR (R 2 = 0.57). In females, SR (R 2 = 0.86), TT (R 2 = 0.85), MSR (R 2 = 0.53) and average BSSR (R 2 = 0.82) were associated with PSLR. Conclusions: SR, TT, MSR and BSSR had moderate criterion related validity for estimating hamstring flexibility in female but not male professional futsal players. The authors recommend that researchers, clinicians, and physical therapists adopt one angular test as a measure of hamstring muscle length in futsal players. [Copyright &y& Elsevier]

The article examines the effect of cognitive anxiety on the biomechanics of the golf swing. Golfers of varying abilities were studied during practice and competition. Human movement analysis software was used to evaluate their swings. Anxiety levels were notably lower during practice. Swings made during competition were far quicker than in practice.

The purpose of this study was to examine the age and sex associated differences in the eccentric/concentric functional ratio for the knee. Isokinetic concentric and eccentric knee extension and flexion was measured at 0.52 rad·s-1 and 3.14rad·s-1 in 121 subjects. Other than mass there were no significant age-by-sex interaction effects for all variables examined. A significant velocity-by-age group effect was demonstrated for ECCKF/CONKE with higher ratios at 3.14 compared to 0.52 rad·s-1. Females' CONKF/ECCKE was significantly lower than males at both velocities. Adults demonstrated significantly lower CONKF/ECCKE than the teenagers at 0.52 rad·s-1 and lower than the prepubertal and teenager groups at 3.14rad·s-1. However, for ECCKF/CONKE at 3.14 rad·s-1, prepubertal ratios were significantly lower than teenagers and adults. The results of the current study suggest that functional rather than conventional ratio should be used when examining knee stability. During fast velocity movements, prepubertal children have a lower capacity for generating eccentric compared to concentric torque. The lower CONKF/ECCKE ratio in adults appears to be due to a greater ability to generate large eccentric torques at all slow and fast movement velocities. The lower CONKF/ECCKE ratio in females is a product of lower concentric torque as opposed to high eccentric torque producing capability as previously thought. [ABSTRACT FROM AUTHOR]

Objective The aim of this study was to evaluate the impact of a centralised referral mechanism (CRM) upon the number and type of 'inappropriate referrals' made to a countywide physical activity referral scheme. Design Case study.Method Phase 1: Hierarchical Content Analysis of 458 'inappropriate referrals' made to a countywide scheme over a 28-month period. Phase 2: Chi-square analysis to compare patients removed on the basis of psychosocial or medical reasons by reason for original referral and gender. One-way ANOVA to compare both groups by age.Results Reasons for referral were classified into first, second and third order themes. Two third level themes emerged from the data: medical contraindicator and psychosocial reasons. Significantly more people were removed on the basis of psychosocial factors rather than medical reasons (chi[2]=77.17; p<0.01). Further those referred for overweight/obesity (chi[2]=49.31; p<0.01) or for musculoskeletal conditions (chi[2]=40.96; p<0.01) were more likely to be removed on the basis of psychosocial factors; whilst those referred for a cardiac condition were more likely to be removed for a medical reason (chi[2]=11.76; p<0.01). Women were significantly (chi[2]=10.78; p<0.01) more likely to be removed for psychosocial reasons. Patients removed from the scheme for medical reasons were also significantly (F=13.00; p<0.01) older than those in the psychosocial group.Conclusions This study provides support for the introduction of a CRM within a countywide physical activity referral scheme. The need for existing referral guidelines to be extended to include holistic recommendations with regard to both the medical conditions that are appropriate for referral and also the stage of readiness of the patient to take-up the referral is recommended. [ABSTRACT FROM AUTHOR]

The aim of this study was to examine the age and sex associated development of time to peak torque (TPT) of the knee and elbow extensors and flexors. 137 subjects participated in this study consisting of three groups aged 9/10 y, 16/17 y and 21+ y. Isokinetic concentric knee and elbow extension and flexion were measured using a calibrated Biodex system 3 and TPT was determined. ANOVA identified significant (p < 0.05) interaction effects for stature and body mass. A main effect for group for knee extension TPT (range 0.20–0.26 s) and elbow flexion TPT (range 0.33–0.40 s) was identified. For elbow flexion the 16/17 y-olds demonstrated significantly faster TPT than the 9/10 y-olds and adults. No significant interaction or main effects for knee flexion (range 0.0.19–0.23 s) or elbow extension (range 0.40–0.44 s) were observed. Pearson product moment correlation coefficients identified no significant relationship between TPT and peak torque for knee and elbow extensors and knee flexors in all groups. A significant negative correlation (p < 0.05) was found for the elbow flexors for both 9/10 y-olds and adults for females but not males. To conclude, no sex differences in TPT of the knee and elbow extensor and flexor muscles were found. Age related changes in TPT appear to be muscle group and muscle action specific and highlight the caution one has to exercise in making assumptions between muscle groups and actions. [ABSTRACT FROM AUTHOR]

This study used multilevel regression modelling to longitudinally investigate the influences of age, sex, body size, skinfold thicknesses and maturity on the development of isokinetic knee extension and flexion on eight occasions over a 4-year period. Forty-one subjects (20 boys and 21 girls) were measured and 295 isokinetic leg strength tests and associated measures were successfully completed. Subjects were aged 10.0 ± 0.3 years at the onset of the study. Stature, body mass, triceps and subscapular skinfold thicknesses, and sexual maturation (according to pubic hair development) were assessed at each test occasion. Isokinetic concentric knee extension and flexion of the dominant leg were determined to elicit maximal peak extension (PET) and flexion torque (PFT). Statistical significance was accepted at p < 0.05. Multilevel regression modelling indicated that stature and mass were significant predictors of both PET and PFT. Age and maturity were non-significant explanatory variables once stature and mass had been accounted for. Skinfold thickness exerted a significant negative effect independent of mass and stature on PFT but not PET. At test occasion 8, cross-sectional areas (CSAs) of the knee extensors (ExCSA) and flexors (FlexCSA) were determined using magnetic resonance imaging on 23 boys and 14 girls and examined as predictors of isokinetic leg strength. There were no significant sex-related differences in PET or PFT. Pearson product moment correlation coefficients indicated a significant relationship between ExCSA and PET and FlexCSA and PFT for both boys and girls. Analysis of covariance (ANCOVA) demonstrated that ExCSA and FlexCSA were significant explanatory variables for PET and PFT, respectively, but became non-significant once stature and mass had been introduced into the analysis. To conclude, there were no significant sex differences in PET or PFT between the ages of 10 and 14 years and the development of PET and PFT could be accounted for by the increase in stature and mass. Age, maturity and thigh muscle CSA were all non-explanatory variables in the production of PET and PFT once body size had been controlled for. [ABSTRACT FROM AUTHOR]

Streptococcus pneumoniae is one of the world's leading bacterial pathogens, causing pneumonia, septicemia, and meningitis. In recent years, it has been shown that genetic rearrangements in a type I restriction-modification system (SpnIII) can impact colony morphology and gene expression. By generating a large panel of mutant strains, we have confirmed a previously reported result that the CreX (also known as IvrR and PsrA) recombinase found within the locus is not essential for hsdS inversions. In addition, mutants of homologous recombination pathways also undergo hsdS inversions. In this work, we have shown that these genetic rearrangements, which result in different patterns of genome methylation, occur across a wide variety of serotypes and sequence types, including two strains (a 19F and a 6B strain) naturally lacking CreX. Our gene expression analysis, by transcriptome sequencing (RNAseq), confirms that the level of creX expression is impacted by these genomic rearrangements. In addition, we have shown that the frequency of hsdS recombination is temperature dependent. Most importantly, we have demonstrated that the other known pneumococcal site-specific recombinases XerD, XerS, and SPD_0921 are not involved in spnIII recombination, suggesting that a currently unknown mechanism is responsible for the recombination of these phase-variable type I systems. [ABSTRACT FROM AUTHOR]

An abstract of the article "Age and Sex Differences in Isokinetic Knee Muscle Endurance Between Young Children and Adults," by M.B.A. De Ste Croix and M.A. Deighan is presented.

Genome-wide association studies (GWAS) with binary or single phenotype data have successfully identified disease-associated genotypes and determinants of antimicrobial resistance. We describe a novel phenotype-to-genotype approach for a major bacterial pathogen that involves simultaneously testing for associations among multiple disease-related phenotypes and linkages between phenotypic variation and genetic determinants. High-throughput assays quantified variation among 163 Neisseria meningitidis serogroup W ST-11 clonal complex isolates for 11 phenotypic traits. A comparison of carriage and two disease subgroups detected significant differences between groups for eight phenotypic traits. Candidate genotypic testing indicated that indels in csw , a capsular biosynthesis gene, were associated with reduced survival in antibody-depleted heat-inactivated serum. GWAS testing detected 341 significant genetic variants (3 single-nucleotide polymorphisms and 338 unitigs) across all traits except serum bactericidal antibody-depleted assays. Growth traits were associated with variants of capsular biosynthesis genes, carbonic anhydrase, and an iron-uptake system while adhesion-linked variation was in pilC2 , marR, and mutS . Multiple phase variation states or combinatorial phasotypes were associated with significant differences in multiple phenotypes. Controlling for group effects through regression and recursive random forest approaches detected group-independent effects for nalP with biofilm formation and fetA with a growth trait. Through random forest testing, nine phenotypes were weakly predictive of MenW:cc11 sub-lineage, original or 2013, for disease isolates while three characteristics separated carriage and disease isolates with >80% accuracy. This study demonstrates the power of combining high-throughput phenotypic testing of pathogenically relevant isolate collections with genomics for identifying genetic determinants of specific disease-relevant phenotypes and the pathobiology of microbial pathogens.IMPORTANCENext-generation sequencing technologies have led to the creation of extensive microbial genome sequence databases for several bacterial pathogens. Mining of these databases is now imperative for unlocking the maximum benefits of these resources. We describe a high-throughput methodology for detecting associations between phenotypic variation in multiple disease-relevant traits and a range of genetic determinants for Neisseria meningitidis , a major causative agent of meningitis and septicemia. Phenotypic variation in 11 disease-related traits was determined for 163 isolates of the hypervirulent ST-11 lineage and linked to specific single-nucleotide polymorphisms, short sequence variants, and phase variation states. Application of machine learning algorithms to our data outputs identified combinatorial phenotypic traits and genetic variants predictive of a disease association. This approach overcomes the limitations of generic meta-data, such as disease versus carriage, and provides an avenue to explore the multi-faceted nature of bacterial disease, carriage, and transmissibility traits.

Introduction: Coaches play a major role in developing movement in their performers, especially at grassroots levels. However, there are significant knowledge gaps amongst grassroots coaches and physical education (PE) teachers regarding movement competency and injury prevention programs. This study aimed to explore the effectiveness of knowledge gain, adoption and implementation following a youth injury prevention workshop for grassroots coaches and PE teachers., Methods: 56 grassroots coaches and PE teachers completed a validated questionnaire exploring use, knowledge, attitude towards and confidence to deliver youth movement competency training before and after an online workshop. Bayesian Wilcoxon signed-rank tests were used to assess the knowledge, attitude, and confidence to deliver an injury prevention programme following the workshop. For all the Bayesian inference tests run, the Bayesian factor (BF 10 ) was interpreted using the evidence categories ranging from extreme evidence (BF 10 > 100) to anecdotical evidence (BF 10 < 1)., Results: Post-workshop there was a 34% increase in respondents indicating that they had greater knowledge of injury prevention issues (55% pre-workshop vs 89% post-workshop) with statistically positive and moderate effects (BF 10 > 100 [extreme evidence]). There was also a 25% increase in respondents indicating that they had a more sympathetic attitude towards injury prevention (67% sympathetic pre-workshop vs 93% sympathetic post-workshop) with statistically moderate effects (BF 10 = 87.4 [very strong evidence]). A 19% increase in attendees' confidence to deliver an injury prevention programme was observed (69% high pre-workshop vs. 89% high post-workshop) with statistically moderate effects (BF 10 = 85.9 [very strong evidence]). 100% of participants indicated an intent to adopt the injury prevention programme., Conclusions: An online workshop increased knowledge and confidence in grassroots coaches and PE teachers to deliver a youth injury prevention programme. Knowledge gained from training and upskilling created a positive attitude and confidence to deliver movement competency into coaching. Appropriate resources need to be developed and delivered in an accessible way to grassroots coaches and PE teachers via workshops and should be included in governing body coaching awards or as continuing professional development for youth coaches and PE teachers.

The objectives of this network meta-analysis were: (a) to estimate and compare the pooled effects of some injury prevention programs (IPPs) whose exercise-based components were categorized using a movement pattern-specific taxonomy on reducing overall and some specific body regions (lower extremity, thigh, knee, and ankle) injury incidences in youth team sport athletes and (b) to explore the individual effects of these components on the injury incidence rates (IIRs) previously mentioned. Searches were performed in PubMed, Web of Science, SPORTDiscus, and Cochrane Library. Eligible criteria were: exercise-based interventions comprised of exercises involving athletic motor skill competencies and evaluated against a control group, overall IIRs were reported, and youth (≤19 years old) team sport players. For the current analysis, a taxonomy based on movement patterns was employed for exercise component identification (upper body pushing and pulling; lower body concentric and eccentric; core; mechanics; acceleration; and lower body stability). Pooled effects were calculated by frequentist random effects pairwise and network meta-analyses. Nineteen studies were included. Most of the IPPs exhibit risk reduction when compared to their control groups on overall, lower extremity, and ankle injuries. Interventions comprised of lower body concentric and eccentric, core, mechanics, and lower body stability exercises were the most effective measures for reducing these injuries. None of the IPPs demonstrated to be effective for reducing thigh injuries, and contradictory results were found for knee injuries. Individual analysis at component level revealed that the lower body (bilateral and unilateral, concentric, and eccentric) component was the only one associated with a significant reduction on overall injuries. Indirect evidence suggests that interventions incorporating lower body concentric and eccentric, core, mechanics, and lower body stability exercises might be the most effective for reducing overall, lower extremity, and ankle injuries in youth team sports.

Evaluation of the apportionment of genetic diversity of human bacterial commensals within and between human populations is an important step in the characterization of their evolutionary potential. Recent studies showed a correlation between the genomic diversity of human commensal strains and that of their host, but the strength of this correlation and of the geographic structure among human populations is a matter of debate. Here, we studied the genomic diversity and evolution of the phylogenetically related oro-nasopharyngeal healthy-carriage Streptococcus mitis and Streptococcus pneumoniae, whose lifestyles range from stricter commensalism to high pathogenic potential. A total of 119 S. mitis genomes showed higher within- and among-host variation than 810 S. pneumoniae genomes in European, East Asian and African populations. Summary statistics of the site-frequency spectrum for synonymous and non-synonymous variation and ABC modelling showed this difference to be due to higher ancestral bacterial population effective size (Ne) in S. mitis, whose genomic variation has been maintained close to mutation-drift equilibrium across (at least many) generations, whereas S. pneumoniae has been expanding from a smaller ancestral bacterial population. Strikingly, both species show limited differentiation among human populations. As genetic differentiation is inversely proportional to the product of effective population size and migration rate (Nem), we argue that large Ne have led to similar differentiation patterns, even if m is very low for S. mitis. We conclude that more diversity within than among human populations and limited population differentiation must be common features of the human microbiome due to large Ne., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2024 Davison et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Background: Reduced dorsiflexion range of motion (DFROM) which is commonly seen following lateral ankle sprain (LAS) has the potential to influence lower extremity biomechanics which have been linked to increased injury risk in the female athlete. Current research on the effect of sex and LAS history on DFROM is limited., Hypothesis/purpose: This study had three aims 1) to determine the effect of sex, leg dominance and LAS history on DFROM, 2) to determine the effect of sex and LAS history on magnitude of DFROM symmetry and 3) to examine the association of sex on direction (whether dominant or non-dominant limb had the higher DFROM) of symmetry., Study Design: Cross-Sectional Study., Methods: DFROM was measured bilaterally in 105 recreational athletes all participating in multidirectional sports using the tape measurement method during the weight bearing lunge test (WBLT). A mean of three measurements was used for analysis. A 3-way mixed ANOVA was carried out to determine the interaction between sex, LAS history and leg dominance on DFROM and a 2-way ANOVA for the effect of sex and LAS history on asymmetry. A chi-square test was used to determine the association of sex and direction of asymmetry., Results: The results indicate no significant effect of sex, LAS history, and leg dominance on DFROM (p=0.65). Main effects were significant for sex and LAS on DFROM. The mean asymmetry for all participants was reported as 12.25±14.76cm. No significant effect of sex and LAS history on magnitude of asymmetry was reported. There was a significant association of sex and direction of asymmetry (χ2(1) = 11.26, p = 0.00). Sixty-five-point two percent of males were shown to have higher DFROM of their non-dominant limb compared to 75% of females who were higher in their dominant limb., Conclusion: Findings from this study suggest that DFROM is affected by sex and LAS history. While females have increased DFROM compared to males, those with LAS history are more likely to have a decreased DFROM on the involved side. The results also indicate that interlimb asymmetries in DFROM are present in athletes, therefore practitioners should exercise caution when using bilateral comparisons in injury and return to play assessments., Level of Evidence: 2b., Competing Interests: The authors report no conflict of interest., (© The Author(s).)

Introduction: Questions continue to be raised about the validity that is in existence to estimate D b , in professional male footballer players., Methods: Phase 1: n  = 28 anthropometric variables were used on n  = 206 footballers, using regression analyses to determine standard error of estimate and R 2 . A cut-off correlation coefficient set at r  = 0.950 and 90% R 2 . Phase 2: all variables ( z -scores, x -  = 0.0, SD = ±1.0) to help reduce heteroscedasticity, β, r , t , significance of t and P- values were calculated. Phase 3: a forced stepwise-backwards regression analysis approach with nine predictors which met the acceptance criteria ( r  = 0.950, R 2  = 90% and β weights) was used to develop a ' best fit ' and a ' practical ' calibration model. Phase 4: cross-validation of the two newly developed calibration method using LoA., Results: The 'best fit' model SEM (0.115 g ml -1 ), the highest R 2 (6.6%) ( P   ≤ 0.005), whereas the 'practical' calibration model SEM (0.115 g ml -1 ), R 2 (4.7%) ( P   ≤ 0.005) with r values = 0.271 and 0.596 and R 2 (%) coefficients = 0.3526 for the 'best fit' and 'practical' calibration models, respectively ( P  = 0.01)., Conclusions: The two calibration models supported an ecologically and statistically valid contribution and can provide sound judgements about professional footballers' body composition.

There is a paucity of literature analyzing the impact of fatigue from actual competitive soccer match-play on measures of neuromuscular function and muscle damage markers in youth players. Aims The main purpose was to analyze the acute pre- and post-competitive soccer match-play changes in measures of landing mechanics, stretch-shortening cycle capability, physical performance, muscle damage, and match intensity. A secondary purpose was to explore whether the players' maturity status and chronological age were associated with post-soccer match-play responses. Methods Thirty-two male youth outfield soccer players from two chronological competition age groups (U14 and U16) were assessed pre-and post-competitive soccer match-play for 2D dynamic knee valgus at landing (DKV), leg stiffness, reactive strength index, 20 m sprint time, CMJ-Abalakov jump height, creatine kinase and urea activity and visual analogue scale for muscle soreness (VAS). Players' maturity status was also estimated using a previously validated regression equation. Results There were statistically significant (p < 0.05) post-competitive soccer match-play impairments in all measures of stretch-shortening cycle capability and muscle damage markers assessed irrespective of the age group. Likewise, significant post-match play alterations in landing mechanics (DKV of the dominant leg) and physical performance (sprint time and jump height) scores were documented for the U14 players. Significant interactions between maturity and landing mechanics and VAS responses to competitive soccer match-play were also found whereby more mature players demonstrated larger post-match changes. Conclusion The findings of this study suggest the existence of a negative influence of competitive match-play on neuromuscular function and muscle damage in youth soccer.

Background: To conduct a systematic review and meta-analysis of epidemiological data of injuries in male and female youth football players., Methods: Searches were performed in MEDLINE/PubMed, Web of Science, Cochrane Library, and SPORTDiscus databases. Studies were considered if they reported injury incidence rate in male and female youth (≤19 years old) football players. Two reviewers (FJRP and ALV) extracted data and assessed trial quality using the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) statement and the Newcastle Ottawa Scale. The Grading of Recommendations Assessment, Development, and Evaluation approach determined the quality of evidence. Studies were combined using a Poisson random effects regression model., Results: Forty-three studies were included. The overall incidence rate was 5.70 injuries/1000 h in males and 6.77 injuries/1000 h in females. Match injury incidence (14.43 injuries/1000 h in males and 14.97 injuries/1000 h in females) was significantly higher than training injury incidence (2.77 injuries/1000 h in males and 2.62 injuries/1000 h in females). The lower extremity had the highest incidence rate in both sexes. The most common type of injury was muscle/tendon for males and joint/ligament for females. Minimal injuries were the most common in both sexes. The incidence rate of injuries increased with advances in chronological age in males. Elite male players presented higher match injury incidence than sub-elite players. In females, there was a paucity of data for comparison across age groups and levels of play., Conclusion: The high injury incidence rates and sex differences identified for the most common location and type of injury reinforce the need for implementing different targeted injury-risk mitigation strategies in male and female youth football players., Competing Interests: Competing interests The authors declare that they have no competing interests., (Copyright © 2021. Production and hosting by Elsevier B.V.)

People Living with HIV (PLHIV) are at an increased risk of pneumococcal pneumonia than HIV-uninfected adults, but the reasons for this are still not well understood. We investigated whether alveolar macrophages (AM) mediated control of pneumococcal infection is impaired in PLHIV compared to HIV-uninfected adults. We assessed anti-bactericidal activity against Streptococcus pneumoniae of primary human AM obtained from PLHIV and HIV-uninfected adults. We found that pneumococcus survived intracellularly in AMs at least 24 hours post ex vivo infection, and this was more frequent in PLHIV than HIV-uninfected adults. Corroborating these findings, in vivo evidence showed that PLHIV had a higher propensity for harboring S. pneumoniae within their AMs than HIV-uninfected adults. Moreover, bacterial intracellular survival in AMs was associated with extracellular propagation of pneumococcal infection. Our data suggest that failure of AMs to eliminate S. pneumoniae intracellularly could contribute to the increased risk of pneumococcal pneumonia in PLHIV., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Nyazika, Sibale, Phiri, De Ste Croix, Jasiunaite, Mkandawire, Malamba, Kankwatira, Manduwa, Ferreira, Nyirenda, Oggioni, Mwandumba and Jambo.)

Abstract: Robles-Palazón, FJ, Ayala, F, Cejudo, A, De Ste Croix, M, Sainz de Baranda, P, and Santonja, F. Effects of age and maturation on lower extremity range of motion in male youth soccer players. J Strength Cond Res 36(5): 1417-1425, 2022-Restricted joint range of motion (ROM) has been considered as a primary risk factor for some sport-related injuries. Consequently, preparticipation assessment of lower extremity joints ROM could help identify youth soccer players at high risk of injury and to aid in the design of tailored age and maturational specific training interventions. The purpose of this study was to analyze and compare the influence of chronological age and maturational stage on several lower extremity ROM measures, as well as to describe the lower extremity ROM profile using a comprehensive approach in youth soccer players. A total of 286 male youth soccer players' ROM were assessed including passive hip (extension [PHE], adduction with hip flexed 90° [PHADHF90°], flexion with knee flexed [PHFKF] and extended [PHFKE], abduction with hip neutral [PHABD] and flexed 90° [PHABDHF90°], external [PHER] and internal [PHIR] rotation), knee (flexion [PKF]) and ankle (dorsiflexion with knee flexed [ADFKF] and extended [ADFKE]) ROMs. Between-group differences were analyzed using a one-way analysis of variance (ANOVA) and magnitude-based decisions. The results only report statistically significant (p < 0.05; d > 0.5) and clinically relevant differences (>8°) for the PKF ROM between U12 vs. U19, and Pre-PHV vs. Post-PHV groups. Furthermore, approximately 40, 35, and 20% of players displayed restrictions in their PHFKE, PKF, and ADFKF ROM values, respectively. These findings emphasize the necessity of prescribing (across all age groups and periods of growth and maturation) compensatory measures in daily soccer training, and these exercises should be equally applied to both limbs with the aim of improving PHFKE, PKF and ADFKF ROM values., (Copyright © 2020 National Strength and Conditioning Association.)

Background: The injury profile of each playing position in handball is a key factor in being able to improve the injury risk management process. Therefore, the aim of this study was to longitudinally analyze the differences in professional handball players' injury profile according to their playing position (ie, goalkeeper, back, wing, and line)., Hypothesis: Injury incidence and burden would be higher in back players compared with the other playing positions, while ligament and knee would be the most common injury type and location., Study Design: Prospective cohort design., Level of Evidence: Level 4., Methods: Sixty-eight male handball players belonging to the same professional team participated in this study over 4 consecutive seasons. Injury incidence and injury burden were recorded as well as the severity, type, and location following the International Olympic Committee consensus statement., Results: Although nonsignificant differences in injury incidence were found according to playing position (rate ratios [RRs] from 0.43 to 2.47; P > 0.05), back players reported the highest burden (60.65 absence days/1000 h; RR from 0.12 to 7.75; P < 0.05), with wing players showing a greater burden (54.29 absence days/1000 h; RR from 0.09 to 4.91; P < 0.05) in comparison with goalkeepers (12.19 absence days/1000 h) and line players (13.10 absence days/1000 h). Muscle/tendon injuries and sprains presented higher incidence and burden than other type of injuries, and a greater incidence and burden was reported for knee injuries in all playing positions., Conclusion: The highest injury incidence and injury burden is in back players in professional handball., Clinical Relevance: This study provides comprehensive information on the injury profile of professional handball players, which can be useful for strength and conditioning coaches when developing specific injury risk management programs.

This study aimed to explore the inter-session reliability of the measures obtained from 2 trunk extension (Biering-Sorensen and Dynamic Extensor Endurance (DEE) tests) and 3 trunk flexion (Ito, Side Bridge and Bench Trunk Curl-Up (BTC) tests) endurance field-based tests in adolescents. A total of 208 (males, n = 100; females, n = 108) adolescents performed all the field-based tests on 2 separate testing sessions, 7-days apart. The inter-session reliability scores were explored through relative reliability, inter-session differences and precision of measurements. Most of the trunk endurance measures demonstrated acceptable relative reliability (the intraclass correlation coefficients (ICC) ranged from 0.75 to 0.94). However, significant inter-session differences were identified for measures from the DEE and BTC tests. Likewise, the precision of the measurement of each field-based test was poor (the the standard error of measurement expressed as a percentage of the mean score (CV TE ) ranged from 11.3 to 24.4%) with the minimal detectable change (MDC 95 ) revealing that changes higher than 42% for trunk extension endurance tests and 31.4% for trunk flexion endurance tests after an intervention are required to indicate a significant change above measurement error. Therefore, the findings from this study indicate that only the BTC test demonstrates acceptable inter-session reliability (ICC > 0.9, CV TE ~ 10%, MDC 95  ~ 30%) to monitor the changes in trunk endurance scores that may be expected in adolescents after performing an intervention programme.

The purposes of this study were to describe the lower extremities joints range of motion (ROM) profile using a comprehensive approach in futsal players and to examine potential player position (goalkeepers vs. outfield players), competitive level (first [top] division vs. second division), number of playing years, sex (males vs. females), and bilateral (dominant limb vs. non-dominant limb) differences. A total of 72 male and 67 female elite futsal players from 11 clubs were measured of passive hip (flexion with knee flexed [HF KF ] and extended [HF KE ], extension [HE], abduction [HA], external [HER], and internal [HIR] rotation), knee (flexion [KF]) and ankle (dorsiflexion with knee flexed [ADF KF ] and extended [ADF KE ]) ROMs. Bayesian inferences exploring differences between player position, competitive level, sex and limb were made. A Bayesian correlation analysis was conducted to explore the influence of playing years on joints ROMs. The results showed no significant player position or competitive level related differences in any average ROM score. However, statistically significant sex-related differences were documented whereby female players reported higher hip and knee joints ROM average values than their male counterparts. Especially relevant were the proportions of males (72%) and players from teams engaged in the second division (61%) displaying limited HF KE ROMs. Likewise, around 35% of all players showed restricted ADF KF ROMs. In addition, approximately 21, 18, 22, and 25% of the futsal players were identified as having bilateral asymmetries (≥8°) for HA, HIR, HER, and KF ROMs, respectively. Finally, Bayesian correlation analysis did not report any significant association between years of playing futsal and ROM measures (all r values < 0.34). The implications that these restricted HF KE and ADF KF ROMs and bilateral asymmetries in hip (abduction, internal and external rotation) and knee (flexion) ROMs caused by the practice of futsal may have on physical performance and injury risk warrant future research., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Cejudo, Ruiz-Pérez, Hernández-Sánchez, De Ste Croix, Sainz de Baranda and Ayala.)

Purpose: To examine the influence of growth and maturation in the trajectory of stretch-shortening cycle capability., Method: Using a mixed-longitudinal design, absolute and relative leg stiffness and reactive strength index (RSI) were measured 3 times over a 3-year period in 44 youth team-sport players. Maturation was determined as maturity offset and included within the Bayesian inference analysis as a covariate alongside chronological age., Results: Irrespective of age and maturation, there was no change in absolute leg stiffness, however relative leg stiffness decreased over time. Maturation and age reduced this decline, but the decline remained significant (Bayesian factor [10] = 5097, model averaged R2 = .61). The RSI increased over time and more so in older more mature youth players (Bayesian factor [10] = 9.29e8, model averaged R2 = .657)., Conclusion: In youth players who are at/post peak height velocity, relative leg stiffness appears to decline, which could have an impact on both performance and injury risk. However, RSI increases during this period, and these data reinforce that leg stiffness and RSI reflect different components of stretch-shortening cycle capability. Practitioners should consider these differences when planning training to maximize stretch-shortening cycle capability during growth and maturation in athletes on the developmental performance pathway.