How Does Ball Possession Affect the Physical Demands in Spanish LaLiga? A Multilevel Approach.

Purpose: Using a multilevel approach, this study analyzed the relationship between ball possession and distance covered at different speed sections: total distance (TD), distance covered between 14.1-21 km·h-1 (MIRD), 21.1-24 km·h-1 (HIRD), and > 24.1 km·h-1 (VHIRD). Methods: The sample included 1,520 matches played by 80 Spanish professional soccer teams across four consecutive LaLiga seasons (from 2015/2016 to 2018/2019). Two observations were collected per match, one from each team, resulting in a total of 2,950 records (760 per season). Data were collected using Mediacoach®. Results: At match level (i.e., grand-mean centered), ball possession negatively predicted all distances covered. At team level (i.e., group-mean centered), ball possession negatively predicted total distance covered and distance covered between 14.1-21 km·h-1. Furthermore, cross-level interactions (Match X Team) in ball possession negatively predicted all distances covered at speeds above 14.1 km·h-1. Specifically, in high-possession teams, the negative relationship between match ball possession and distances traveled at all speed ranges above 14.1 km·h-1 was stronger than in teams with medium or low possession. Conversely, match ball possession was positively related todistance covered at low intensities, and negatively related at high intensities in low-possession teams. Conclusion: These findings show practitioners and researchers that the distances covered at different speed ranges depend on technical-tactical parameters such as ball possession.

Consistency and identifiability of football teams: a network science perspective.

We investigated the ability of football teams to develop a particular playing style by looking at their passing patterns. Using the information contained in the pass sequences during matches, we constructed the pitch passing networks of teams, whose nodes are the divisions of the pitch for a given spatial scale and links account for the number of passes from region to region. We translated football passings networks into their corresponding adjacency matrices. We calculated the correlations between matrices of the same team to quantify how consistent the passing patterns of a given team are. Next, we quantified the differences with other teams' matrices and obtained an identifiability parameter that indicates how unique are the passing patterns of a given team. Consistency and identifiability rankings were calculated during a whole season, allowing to detect those teams of a league whose passing patterns are different from the rest. Furthermore, we found differences between teams playing at home or away. Finally, we used the identifiability parameter to investigate what teams imposed their passing patterns over the rivals during a given match.

Revisión sistemática de los métodos predictores de la funcionalidad del trasplante renal / Systematic review of kidney transplantation functional predictors

Contexto: El trasplante renal de donantes con criterios expandidos ha aumentado el pool de riñones a costa de un riesgo superior de disfunción del injerto a corto y/o largo plazo. La cuestión principal reside en determinar qué riñones ofrecerán una función y supervivencia aceptables comparado con el riesgo que supone la cirugía y la posterior inmunosupresión. Objetivo: El objetivo de nuestro artículo es revisar la evidencia actual sobre las herramientas para predecir la funcionalidad del trasplante renal de donantes de cadáver con criterios expandidos y determinar la validez para su uso en la práctica habitual. Adquisición de evidencia: Hemos realizado una revisión sistemática de la literatura según los criterios PRISMA, a través de Medline (http://www.ncbi.nlm.nih.gov), utilizando las palabras clave, aisladas o conjuntamente: cadaveric renal transplantation; kidney graft function appraisal; graft function predictors. Se seleccionaron series prospectivas y retrospectivas, así como artículos de revisión. Un total de 375 artículos fueron analizados, de los cuales 39 fueron finalmente seleccionados para revisión. Síntesis de evidencia: Entre los predictores de la funcionalidad se encuentran: los índices de riesgo del donante; el cálculo del peso funcional renal o la valoración de la masa nefrónica; la medición de las resistencias vasculares durante la perfusión en hipotermia; la medición de biomarcadores en la orina del donante y en el líquido de perfusión; la medición de parámetros funcionales y de reperfusión en normotermia y la medición de los parámetros morfológicos, micro y macroscópicos, del órgano diana. En este artículo presentamos un resumen explicativo de cada uno de estos parámetros, así como su evidencia más reciente al respeto. Discusión: Ningún parámetro de los revisados fue capaz de predecir por sí mismo, con fiabilidad, la función renal y la supervivencia del trasplante. Existe un importante vacío en cuanto a la valoración macroscópica del trasplante renal. Conclusiones: Es necesario continuar desarrollando los predictores de la funcionalidad renal para definir con precisión la distribución de cada uno de los riñones de los donantes que disponemos en la actualidad

Context: Kidney transplantation from donors with expanded criteria has increased the pool of kidneys at the cost of a higher risk of short and long-term graft dysfunction. The main issue lies in determining which kidneys will offer acceptable function and survival compared with the risk represented by surgery and subsequent immunosuppression. Objective: The objective of our article is to review the current evidence on the tools for predicting the functionality of kidney transplantation from cadaveric donors with expanded criteria and determining the validity for their use in standard practice. Acquisition of evidence: We conducted a systematic literature review according to the PRISM criteria, through Medline (http://www.ncbi.nlm.nih.gov) and using the keywords (in isolation or in conjunction) "cadaveric renal transplantation; kidney graft function appraisal, graft function predictors". We selected prospective and retrospective series and review articles. A total of 375 articles were analysed, 39 of which were ultimately selected for review. Summary of the evidence: The predictors of functionality include the following: The donor risk indices; the calculation of the renal functional weight or the assessment of the nephronic mass; the measurement of vascular resistances during perfusion in hypothermia; the measurement of the donor's biomarkers in urine and in the perfusion liquid; the measurement of functional and reperfusion parameters in normothermia; and the measurement of morphological parameters (microscopic and macroscopic) of the target organ. In this article, we present an explanatory summary of each of these parameters, as well as their most recent evidence on this issue. Discussion: None of the reviewed parameters in isolation could reliably predict renal function and graft survival. There is a significant void in terms of the macroscopic assessment of kidney transplantation. Conclusions: We need to continue developing predictors of renal functionality to accurately define the distribution of each currently available donor kidney

Systematic review of kidney transplantation functional predictors. / Revisión sistemática de los métodos predictores de la funcionalidad del trasplante renal.

CONTEXT: Kidney transplantation from donors with expanded criteria has increased the pool of kidneys at the cost of a higher risk of short and long-term graft dysfunction. The main issue lies in determining which kidneys will offer acceptable function and survival compared with the risk represented by surgery and subsequent immunosuppression. OBJECTIVE: The objective of our article is to review the current evidence on the tools for predicting the functionality of kidney transplantation from cadaveric donors with expanded criteria and determining the validity for their use in standard practice. ACQUISITION OF EVIDENCE: We conducted a systematic literature review according to the PRISM criteria, through Medline (http://www.ncbi.nlm.nih.gov) and using the keywords (in isolation or in conjunction) "cadaveric renal transplantation; kidney graft function appraisal, graft function predictors". We selected prospective and retrospective series and review articles. A total of 375 articles were analysed, 39 of which were ultimately selected for review. SUMMARY OF THE EVIDENCE: The predictors of functionality include the following: The donor risk indices; the calculation of the renal functional weight or the assessment of the nephronic mass; the measurement of vascular resistances during perfusion in hypothermia; the measurement of the donor's biomarkers in urine and in the perfusion liquid; the measurement of functional and reperfusion parameters in normothermia; and the measurement of morphological parameters (microscopic and macroscopic) of the target organ. In this article, we present an explanatory summary of each of these parameters, as well as their most recent evidence on this issue. DISCUSSION: None of the reviewed parameters in isolation could reliably predict renal function and graft survival. There is a significant void in terms of the macroscopic assessment of kidney transplantation. CONCLUSIONS: We need to continue developing predictors of renal functionality to accurately define the distribution of each currently available donor kidney.