If You Want to Prevent Hamstring Injuries in Soccer, Run Fast: A Narrative Review about Practical Considerations of Sprint Training.

Hamstring strain injuries (HSIs) are one of the most common injuries in sprint-based sports. In soccer, the ability to sprint is key, not only because of its relation to performance but also due to its possible protective effect against HSIs. Although many authors have focused on the "how", "when", and "what" training load should be implemented, there is a lack of practical proposals for sprint training in a high-level professional environment. The objective of this narrative review is, after a deep review of the scientific literature, to present a practical approach for sprint training, trying to answer some of the questions that most strength and conditioning coaches ask themselves when including it in soccer. Once the literature published on this topic was reviewed and combined with the practical experience of the authors, it was concluded that sprint training in soccer, although it presents an obvious need, is not something about which there is methodological unanimity. However, following the practical recommendations from this narrative review, strength and conditioning coaches can have a reference model that serves as a starting point for optimal management of the internal and external training load when they wish to introduce sprint training in the competitive microcycle in professional soccer players, with the aim of reducing HSIs.

Weekly Programming of Hamstring-Related Training Contents in European Professional Soccer.

Hamstring injuries in soccer continue to be a challenge for professionals who work with soccer players daily. Although its origin is multifactorial, the proper management of neuromuscular fatigue during the training microcycle is a very important factor to consider. There are no clear guidelines regarding the weekly distribution of certain exercises that demand the hamstrings. The main objective of this study was to describe the usual training practices of professional European soccer teams. An international observational survey design was applied to some of the strength and conditioning coaches of professional soccer teams. The survey included different neuromuscular demanding exercises for the hamstrings. For each exercise, the strength and conditioning coaches had to respond in relation to their frequency of use and timepoint depending on the day of the weekly microcycle. Although there is no strong consensus in this regard, there does seem to be a trend when applying certain exercises, especially on the days matchday-4 and matchday-3.

Baby led weaning, ¿seguro y eficaz? Una revisión narrativa / Baby led weaning, safe and effective? A narrative review

Introducción: el baby led weaning (BLW) o destete dirigido por el bebé es una técnica de alimentación complementaria que se ha puesto de moda en los últimos años gracias principalmente a su difusión por internet. Objetivo: determinar si dos de las principales críticas recibidas por este método (riesgo de atragantamiento y déficits nutricionales) son reales en comparación con otras técnicas de alimentación complementaria. Metodología: revisión narrativa de estudios de cohorte y diseños aleatorizados publicados en los últimos años en las bases de datos PubMed y Google Scholar. Resultados: once trabajos (siete relacionados con el atragantamiento y cuatro vinculados con los déficits nutricionales) fueron incluidos y analizados en esta revisión. Conclusiones: el BLW se presenta como una técnica de alimentación complementaria segura ya que no presenta más riesgo de atragantamiento que otras. En relación a su eficacia nutricional, no existe una evidencia sólida en relación a la exposición de alimentos ricos en hierro en niños que siguen el BLW con respecto a niños que siguen otra técnica (AU)

Introduction: the baby led weaning (BLW), or weaning directed by the baby, is a complementary feeding technique that has become fashionable in recent years thanks mainly to its diffusion on the internet. Objective: to determine if two of the main criticisms received by this method (risk of choking and nutritional deficits) are real compared to other complementary feeding techniques. Methodology: narrative review of cohort studies and randomized designs published in recent years in the PubMed and Google Scholar databases. Results: eleven works (seven related to choking and four related to nutritional deficits) were included and analyzed in this review. Conclusions: the BLW is presented as a safe complementary feeding technique since it presents no more choking risk than others. Regarding their nutritional efficacy, there is no solid evidence regarding the exposure of iron-rich foods in children who follow the BLW with respect to children who follow another technique (AU)

The Domestic Environment and the Lung Mycobiome.

This study analyzes the relationship between the mycobiome of the Lower Respiratory Tract (LRT) and the fungi in the domestic environment. Samples studied consisted of Broncho-Alveolar Lavage (BAL) from 45 patients who underwent bronchoscopy for different diagnostic purposes, and dust and air from the houses (ENV) of 20 of them (44.4%). Additionally, five bronchoscopes (BS) were also analyzed and negative controls were included for every procedure. All samples were processed for DNA extraction and cultures, which were performed in Sabouraud Dextrose and Potato Dextrose Agar. The fungal Internal Transcribed Spacer (ITS2) was sequenced by the Solexa/Illumina system and sequences were analyzed by QIIME 1.8.0 and compared with the UNITE Database for identification. The similarity between the two fungal communities (BAL and ENV) for a specific patient was assessed via the percentage of coincidence in the detection of specific operational taxonomic units (OTUs), and about 75% of co-occurrence was detected between the mycobiome of the LRT and the houses. Cultures confirmed the presence of the core mycobiome species. However, the low rate of isolation from BAL suggests that most of its mycobiome corresponds to non-culturable cells. This likely depends on the patient's immune system activity and inflammatory status.

Corrigendum: Strength, Jumping, and Change of Direction Speed Asymmetries Are Not Associated With Athletic Performance in Elite Academy Soccer Players.

[This corrects the article DOI: 10.3389/fpsyg.2020.00175.].

Strength, Jumping, and Change of Direction Speed Asymmetries Are Not Associated With Athletic Performance in Elite Academy Soccer Players.

The aims of the present study were 2-fold: (1) to measure interlimb asymmetries from a battery of fitness tests in youth soccer players and (2) to determine the association between asymmetry and measures of athletic performance. Sixteen elite youth soccer players (14.7 ± 0.2 years) performed a single-leg Abalakov test (ABK), change of direction (COD) test over 10 m (5 + 5) and 20 m (10 + 10), and an iso-inertial power test. Subjects also performed 10-, 20-, and 30-m sprints and a bilateral countermovement jump, which were correlated with all ABK, COD, and iso-inertial asymmetry scores. A one-way repeated-measures analysis of variance showed significant differences between interlimb asymmetry scores across multiple tests (p < 0.05), with the iso-inertial power test presenting the greatest magnitude of asymmetry, whereas individual data highlighted substantially greater interindividual differences in each test. Pearson r correlations showed no significant relationships (p > 0.05) between the different interlimb asymmetry scores, and between asymmetry scores and athletic performance. These findings show the test-specific nature of asymmetries in youth soccer players, with the iso-inertial power test being the most sensitive in detecting asymmetry. Moreover, the results obtained suggest that inherent asymmetry in young soccer players did not negatively impact their performance.

Psychometric Analysis and Effectiveness of the Psychological Readiness of Injured Athlete to Return to Sport (PRIA-RS) Questionnaire on Injured Soccer Players.

The decision-making process about when an athlete may safely return to training and competition after an injury is a difficult decision. Safe return to training and competition is characterised by physical and psychological readiness to return to the sport. The objectives of this study are (1) to assess the measurement properties of the Psychological Readiness of Injured Athlete to Return to Sport questionnaire (PRIA-RS), and (2) to analyse the effectiveness which the PRIA-RS questionnaire possesses when applied during four consecutive seasons on professional soccer players. One hundred and nine male soccer players from the Albacete Soccer Club (Spain) were involved during four consecutive seasons for the current study: 2012-2013, 2013-2014, 2014-2015 and 2015-2016. Psychometric analysis (validity, reliability, internal consistency and effectiveness) and external psychometric analysis (evaluating measures of patient-reported outcomes (EMPRO)) were confirmed and supported. The main results of the study reveal that the psychometric properties of this questionnaire are optimum for their application in a professional sports context.

Traducción y adaptación al inglés de un cuestionario para determinar la predisposición psicológica del futbolista lesionado / Translation and adaptation to English of a questionnaire to determine the Psychological readiness of the injured football player / Tradução e adaptação ao inglês de um questionário para determinar a predisposição psicológica do jogador lesionado Resumo

Diferentes estudios han mostrado que una mala predisposición psicológica del deportista lesionado podría dificultar su retorno a los entrenamientos. El objetivo de este trabajo consistió en traducir y adaptar del castellano al inglés el cuestionario de predisposición psicológica para deportistas lesionados. Se utilizó una metodología de traducción-retrotraducción con traductores nativos y expertos en el campo de la recuperación de lesiones. Los traductores encontraron una equivalencia conceptual alta entre ambas versiones, así como un nivel de dificultad para su traducción bajo. El cuestionario PRIA-RS se presenta como una versión válida conceptual y contextualmente cuyo uso a nivel internacional, gracias a esta nueva versión en inglés, podría verse incrementado

Different studies have shown that a bad psychological predisposition of the injured athlete could hinder his return to training. The aim of this work was to translate and adapt the questionnaire of psychological predisposition for injured athletes from Spanish to English. A translation-backtranslation methodology was used with native translator and experts in the field of injury recovery. The translators found a high conceptual equivalence between both versions, as well as a low level of difficulty for their translation. The PRIA-RS questionnaire is presented as a conceptually and contextually valid version. Its use at the international level, thanks to this new version in English, could be increased

Diferentes estudos mostraram que uma má predisposição psicológica do atleta lesionado poderia dificultar seu retorno ao treinamento. O objetivo deste trabalho foi traduzir e adaptar o questionário de predisposição psicológica para atletas lesionados do espanhol para o inglês. Uma metodologia de tradução de tradução reversa foi usada com tradutores nativos e especialistas no campo da recuperação de lesões. Os tradutores encontraram uma alta equivalência conceitual entre as duas versões, bem como um nível de dificuldade para sua baixa tradução. O questionário PRIA-RS é apresentado como uma versão conceitual e contextualmente válida, cuja utilização em nível internacional, graças a essa nova versão em inglês, poderia ser aumentada

Decisiones «inteligentes» y Return to Play / Smart decisions and return to play

No disponible

Use of functional performance tests in sports: Evaluation proposal for football players in the rehabilitation phase.

OBJECTIVES: Based on the criteria of a group of experts, this study aims to select a set of functional performance tests which can be applied to evaluate the functional status of a football player in the recovery process and make a decision in relation to their return to practice. MATERIALS AND METHODS: A total of 16 experts were selected by the coordinator group to judge an initial list of functional performance tests and, thus, reach a consensus about the tests which are best suited to the needs of the injured player. Each of the experts had to evaluate each one of the tests in a scale from 1 to 5 in relation to their suitability. Delphi method was used to reach consensus in the expert group. RESULTS: From the initial list of 25, the tests which obtained the best evaluation were: Counter movement jump (4.3±0.9), Single hop test (4.1±0.8), Triple hop test (4.1±0.9), Crossover hop test (4.1±0.7), Yo-Yo intermittent recovery (4.2±0.6), Barrow test (4.1±0.6), Shuttle run 8¥5 m (4.1±0.8). Star excursion balance test (4±0.7) and Y balance test (4.1±0.7). CONCLUSION: In the opinion of the experts selected here, these tests are the ones which best respond to the needs involved in a complex decision such as RTP.

Functional Assessment and Injury Risk in a Professional Soccer Team.

At the last World Conference on Sport and Physical Therapy celebrated in Bern (Switzerland, 2015), it was confirmed that the functional skills of an athlete are a very important variable to be considered in the recovery of an injury. On the other hand, its use as a predictive risk tool still lacks solid evidence. The purpose of this study was to determine whether a battery of functional tests (FPT) could be used as a preliminary measure for the season in order to identify the injury risk in a professional soccer team in the Spanish Second Division B League. Fifty-two soccer players (ages of 25.3 ± 4.6 years, 10.33% ± 0.9% fat) were functionally assessed during two seasons (2012⁻2013 and 2013⁻2014) and analyzed from an injury perspective. A total of 125 injuries were recorded. The sample was grouped based on the number of injuries and the required absence days. Except for the bipodal vertical jump (CMJ), none of the functional tests revealed differences among the groups. The correlation study between the functional condition and the suffered injuries did not show any significant results.

A propósito del “Return to play” en futbolistas lesionados / About the Return to Play on injured football players

No disponible

Seguimiento longitudinal de la evolución en la condición aeróbica en jóvenes futbolistas / Longitudinal tracing of aerobic condition's evolution in young soccer players

ObjetivoEl objetivo del presente estudio fue determinar el comportamiento de los principales factores condicionantes de la condición aeróbica en jóvenes futbolistas (15–18 años).ProcedimientoPara ello, se estudió a una muestra de 79 jugadores pertenecientes a los equipos inferiores del Albacete Balompié y que habían pasado al menos 2 pruebas de esfuerzo en el periodo de las temporadas 00/01–07/08.Se obtuvieron datos sobre el consumo máximo de oxígeno (VO2max), la FC máxima, la velocidad máxima alcanzada en el momento del máximo consumo de oxígeno y el porcentaje de VO2max al que se producía el umbral anaeróbico.ConclusionesEl consumo máximo de oxígeno relativo como máximo exponente de la potencia aeróbica de un sujeto no sufre modificaciones significativas durante el periodo de edad de los 15–18 años.La economía de carrera medida mediante la capacidad de generar velocidad (velocidad de desplazamiento) a una intensidad dada mejora durante la pubertad, para estabilizarse a partir de los 17 años.La FC máxima se reduce durante la adolescencia a razón de 7–8 pulsaciones cada 5 años.No existen diferencias entre los porcentajes de VO2max a los que los jugadores de 15–18 años experimentan su umbral anaeróbico(AU)

GoalThe aim of the present study was to determine the behaviour of the main factors of aerobic condition in young soccer players (15–18 years).ProcessFor this, we studied 79 subjects who belong to Albacete Balompié's young teams. These players passed two effort tests at least during the period (00/01–07/08).We obtained data about the maximum oxygen intake (VO2max), maximum heart rate, maximum speed at the moment of VO2max and the percentage of VO2max when the anaerobic threshold happenesConclusionsMaximal oxygen intake like exponent of aerobic power doesn't experiment significant changes during ages 15 to 18.Run's economy improves during puberty and stabilizes as of 17 years.Maximal heart rate decrease during adolescence us 7–8 beat each 5 years.There aren't differences between VO2max's percentages which 15–18 players experiment their anaerobic threshold(AU)

Both abscisic acid (ABA)-dependent and ABA-independent pathways govern the induction of NCED3, AAO3 and ABA1 in response to salt stress.

The responsiveness of plants to osmotic stress is critically mediated by the increase in abscisic acid (ABA) levels. Osmotic stress induces the biosynthesis of ABA, whose increased levels subsequently exert a positive feedback on its own biosynthetic pathway. As only qualitative or semi-quantitative analyses were performed to test the inducibility of ABA biosynthetic genes in Arabidopsis thaliana, we used quantitative reverse transcriptase-polymerase chain reaction to re-examine the induction of the ABA1, ABA2, ABA3, NCED3 and AAO3 genes by NaCl and ABA. Quantitative gene expression data obtained from wild-type plants and severely ABA-deficient mutants support the prevailing notion that the 9-cis-epoxycarotenoid cleavage reaction is the key regulatory step in NaCl-induced ABA biosynthesis. Interestingly, strong induction by NaCl of NCED3 was still observed in severe ABA-deficient mutants, pointing to an ABA-independent induction pathway for NCED3 that is NaCl-dependent. Therefore, in the absence of the ABA-mediated positive feedback on ABA biosynthesis, the ABA-independent pathway makes a major contribution to the induction of key ABA biosynthetic genes, such as NCED3, AAO3 and ABA1. In addition, and in contrast to some previous reports, our data do not support the limited ability of ABA to induce NCED3 expression. Under our experimental conditions, the induction of NCED3 by ABA, either in wild-type plants or ABA-deficient mutants, was predominant over that of other ABA biosynthetic genes. Natural variability was found in the induction by NaCl and ABA of NCED3 and ABA1 expression in different Arabidopsis accessions, although NCED3 expression was clearly predominant.

A mutational analysis of the ABA1 gene of Arabidopsis thaliana highlights the involvement of ABA in vegetative development.

Much of the literature on the phytohormone abscisic acid (ABA) describes it as a mediator in triggering plant responses to environmental stimuli, as well as a growth inhibitor. ABA-deficient mutants, however, display a stunted phenotype even under well-watered conditions and high relative humidity, which suggests that growth promotion may also be one of the roles of endogenous ABA. Zeaxanthin epoxidase, the product of the ABA1 gene of Arabidopsis thaliana, catalyses the epoxidation of zeaxanthin to antheraxanthin and violaxanthin, generating the epoxycarotenoid precursor of the ABA biosynthetic pathway. This paper gives a description of the molecular and phenotypic characterization of a large series of mutant alleles of the ABA1 gene, which cause different degrees of ABA deficiency, four of them previously isolated (aba1-1, aba1-3, aba1-4, and aba1-6) and the remaining five novel (sañ1-1, sañ1-2, sañ1-3, sañ1-4, and sre3). Molecular analysis of these alleles provides insights into the domains in which they compromise zeaxanthin epoxidase function. The size of the leaves, inflorescences, and flowers of these mutants is reduced, and their rosettes have lower fresh and dry weights than their wild types, as a result of a diminished cell size. Low concentrations of exogenous ABA increase the fresh weight of mutant and wild-type plants, as well as the dry weight of the mutants. The leaves of aba1 mutants are abnormally shaped and fail to develop clearly distinct spongy and palisade mesophyll layers. Taken together, these phenotypic traits indicate, as suggested by previous authors, that ABA acts as a growth promoter during vegetative development. The abnormal shape and internal structure of the leaves of aba1 mutants suggests, in addition, a role for ABA in organogenesis.

Genetic architecture of NaCl tolerance in Arabidopsis.

The little success of breeding approaches toward the improvement of salt tolerance in crop species is thought to be attributable to the quantitative nature of most, if not all the processes implicated. Hence, the identification of some of the quantitative trait loci (QTL) that contribute to natural variation in salt tolerance should be instrumental in eventually manipulating the perception of salinity and the corresponding responses. A good choice to reach this goal is the plant model system Arabidopsis, whose complete genome sequence is now available. Aiming to analyze natural variability in salt tolerance, we have compared the ability of 102 wild-type races (named ecotypes or accessions) of Arabidopsis to germinate on 250 mM NaCl, finding a wide range of variation among them. Accessions displaying extremely different responses to NaCl were intercrossed, and the phenotypes found in their F(2) progenies suggested that natural variation in NaCl tolerance during germination was under polygenic controls. Genetic distances calculated on the basis of variations in repeat number at 22 microsatellites, were analyzed in a group of either extremely salt-tolerant or extremely salt-sensitive accessions. We found that most but not all accessions with similar responses to NaCl are phylogenetically related. NaCl tolerance was also studied in 100 recombinant inbred lines derived from a cross between the Columbia-4 and Landsberg erecta accessions. We detected 11 QTL harboring naturally occurring alleles that contribute to natural variation in NaCl tolerance in Arabidopsis, six at the germination and five at the vegetative growth stages, respectively. At least five of these QTL are likely to represent loci not yet described by their relationship with salt stress.

The short-chain alcohol dehydrogenase ABA2 catalyzes the conversion of xanthoxin to abscisic aldehyde.

Mutants able to germinate and perform early growth in medium containing a high NaCl concentration were identified during the course of two independent screenings and named salt resistant (sre) and salobreño (sañ). The sre and sañ mutants also were able to germinate in high-osmoticum medium, indicating that they are osmotolerant in a germination assay. Complementation analyses revealed that sre1-1, sre1-2, sañ3-1, and sañ3-2 were alleles of the abscisic acid (ABA) biosynthesis ABA2 gene. A map-based cloning strategy allowed the identification of the ABA2 gene and molecular characterization of four new aba2 alleles. The ABA2 gene product belongs to the family of short-chain dehydrogenases/reductases, which are known to be NAD- or NADP-dependent oxidoreductases. Recombinant ABA2 protein produced in Escherichia coli exhibits a K(m) value for xanthoxin of 19 micro M and catalyzes in a NAD-dependent manner the conversion of xanthoxin to abscisic aldehyde, as determined by HPLC-mass spectrometry. The ABA2 mRNA is expressed constitutively in all plant organs examined and is not upregulated in response to osmotic stress. The results of this work are discussed in the context of previous genetic and biochemical evidence regarding ABA biosynthesis, confirming the xanthoxin-->abscisic aldehyde-->ABA transition as the last steps of the major ABA biosynthetic pathway.