Osgood-Schlatter disease is the most common osteochondritis of the lower limb in sport-practicing children and adolescents. Its manifestation usually coincides with the appearance of the secondary ossification center of the tibia and is linked to the practice of sports with an explosive component. In the present study, a review of the factors related to its appearance, diagnosis and treatment was carried out. Its appearance seems to be multifactorial and related to multiple morphological, functional, mechanical and environmental factors. Given all the above, risk factor reduction and prevention seem the most logical strategies to effectively prevent the appearance of the condition. In addition, it is essential to create prevention programs that can be objectively assessed and would allow to stop the progress of the pathology, particularly in those sports where high forces are generated on the insertion zone of the patellar tendon at sensitive ages. More studies are needed to clarify which type of treatment is the most appropriate—specific exercises or the usual care treatment.

The potential for assessing performance and acute fatigue in uphill trail running (UTR) through acceleration time series remains underexplored. For this purpose, time-variability of body acceleration and covariation among limb acceleration were studied in UTR. Twenty competitive and young trail runners participated in a simulation UTR test covering a distance of 4758 meters, with a total elevation gain of 575 meters and an average slope of 13.6%. Four sections with clear slope differences were identified. Detrended Fluctuation Analysis of upper back acceleration and Principal Component Analysis among wrists and ankle acceleration were performed for the whole test and for each section.The outcomes were correlated with performance and standardized effect size was used to compare sections. The main findings suggest that (a) runners with higher performance showed less persistence in body acceleration fluctuations and greater interlimb diversity, and (b) the steepest parts, particularly the final and effortful section, showed increased persistence in body acceleration and some runners lost interlimb covariation.In conclusion, time-variability and coordination analyses of acceleration time series seem to be sensitive to performance and acute fatigue in UTR, which opens further possibilities for providing more integrative, dynamic, and practical assessment tools.

Objectives: The aim was to assess the content validity of a new field test on general and soccer-specific motor skills before return to play. Methods: The RONDO-TEST was assessed by a Delphi panel for its content validity. It included a survey to evaluate 16 items related to the test consisting of four 10 m lines which cross over at their mid-point, resulting in eight 5 m sectors that include locomotor skills (speeding, moving sideways, side cutting, and jumping) and soccer-specific technical skills (dribbling, slalom course, and kicking/passing). The content validity was calculated with the Aiken’s V coefficient of acceptance at 0.69 and 95% of confidence interval. Results: Eight experts participated in the Delphi and agreed on the administration procedures after three rounds of suggestions. Major changes included the order of execution and the descriptions of the sectors. The results showed consensus (V = 1, maximum acceptance) for the clarity of instructions, the relevance of the skills to be evaluated, the order of execution, the materials and the relevance of measuring total and partial sector times. Conclusions: The RONDO-TEST may be feasible and simple to administer and evaluate technical functional skills (actions) and condition-related abilities (e.g., the ability to repeat the test, fatigue curve, etc.), which are relevant aspects for return to play under optimum conditions.

Introduction: Evidence has shown physical exercise leads health benefits in breast cancer survivors, for example reducing return-to-work (RTW) time. However, what exercise component has (if any) the greatest impact on the recovery time after breast cancer. The aim of this study is to determine the exercise load variables (type, frequency, intensity, exercise time, volume, density and progression) that are best associated with recovery time in female breast cancer survivors (measured as time off work). Methods: In this systematic review, we included experimental, cohort, and observational studies of female breast cancer survivors engaging in physical exercise programs. We searched PubMed, Web of Science, Sport Discus, and Scopus (Sep 2021-Sep 2022) using the PICOS strategy and PRISMA 2020 guidelines. Studies were independently screened and data extracted into a database, focusing on exercise variables association with return-to-work time. Methodological quality was assessed using ROB 2.0, considering study design, intervention details, and bias risk. Results: Following screening, seven studies were included in this review, with five defining a minimum of one exercise component. Two studies specified frequency and density, while three defined the type, frequency, volume, intensity, density, and progression of interventions. No study found a direct correlation between exercise components and RTW time. Conclusions: In the literature reviewed in this systematic review, it is not possible to identify which exercise variable(s) have the strongest correlation with RTW outcomes. The existing studies demonstrate a lack of comprehensive intervention descriptions, limiting our understanding of the distinct exercise components and their potential effects on RTW results.

Introducción y objetivo: El fútbol es un deporte colectivo en constante evolución que en los últimos años ha incrementado el interés por las capacidades condicionales de los jugadores debido a su posible relación con el rendimiento deportivo. Conocer las demandas exigidas por la competición permite mejorar el diseño y periodización de los entrenamientos. El objetivo principal de este trabajo fue explorar y analizar las demandas físicas soportadas por los jugadores profesionales de fútbol en competición en los últimos años, centrándose en variables de distancia recorrida en campo. Metodología: Siguiendo las pautas de la declaración PRIMSA se realizó una revisión sistemática con las bases de datos de Sportdiscuss, PubMed y Scopus. Se incluyeron aquellos estudios relacionados con las demandas de distancias absolutas recorridas por los jugadores en partidos de fútbol FIFA masculino profesional y en los que se expresaran los resultados en colectivos y por posiciones. Se seleccionaron 17 estudios y se evaluó su calidad metodológica con la herramienta ROB 2.0. Resultados y conclusiones: Los resultados muestran que los jugadores recorren una media de 10289,20m de distancia total por partido siendo los mediocentros los jugadores que mayor distancia recorren. Al mismo tiempo se encontró que los jugadores recorren una mediana de 501m de distancia a alta velocidad, siendo los jugadores exteriores y/o los delanteros los que obtuvieron mayores velocidades.