Injuries according to the percentage of adult height in an elite soccer academy.

OBJECTIVES: This study aimed to ascertain if there is a defined pattern of injury related to the percentage of attained adult height and classify injuries according to maturity status bands. DESIGN: Prospective cohort study. METHODS: From 1998-2019, 63 elite male soccer players of at least the U12 category from a Spanish LaLiga club's academy were followed until reaching their final height. Medical staff recorded injuries following the FIFA consensus and measured height 2-3 times per season. The percentage of adult height at which each injury occurred was calculated using the player's closest height to the injury and his final adult height. Injuries were classified in maturity bands, pre-peak-height-velocity (PHV) <88%, circa-PHV 88%-96%, and post-PHV >96%. RESULTS: There were 509 injuries among the 63 players. Growth-related injuries occurred at a median (IQR) of 91.2% (86.7%-95.2%) of adult height, predominating in pre-PHV and PHV bands. Muscle injuries predominantly occurred at post-PHV, with 77.78% of those conditions occurring within that time frame and at 98.7% (96%-99.5%) of adult height. Likewise, knee and ankle joint/ligament injuries predominated at post-PHV (87% and 65% of total cases, respectively) occurring at 99.0% (97.9%-99.9%) and 98.4% (89.2%-99.4%) of adult height, respectively. CONCLUSIONS: Injuries follow a specific pattern according to the percentage of adult height.

A comparison of injuries in elite male and female football players: A five-season prospective study.

The aim was to compare the epidemiology of injuries between elite male and female football players from the same club. Injuries and individual exposure time in a male team and a female team, both playing in the Spanish first division, were prospectively recorded by the club's medical staff for five seasons (2010-2015) following the FIFA consensus statement. Total, training, and match exposure hours per player-season were 20% higher for men compared to women (P<.01). Total, training, and match injury incidence were 30%-40% higher in men (P≤.04) mainly due to a 4.82 (95% confidence interval [CI] 2.30-10.08) times higher incidence of contusions, as there were no differences in the incidence of muscle and joint/ligament injuries (P≥.44). The total number of absence days was 21% larger in women owing to a 5.36 (95% CI 1.11-25.79) times higher incidence of severe knee and ankle ligament injuries. Hamstring strains and pubalgia cases were 1.93 (95% CI 1.16-3.20) and 11.10 (95% CI 1.48-83.44) times more frequent in men, respectively; whereas quadriceps strains, anterior cruciate ligament ruptures, and ankle syndesmosis injuries were 2.25 (95% CI 1.22-4.17), 4.59 (95% CI 0.93-22.76), and 5.36 (95% CI 1.11-25.79) times more common in women, respectively. In conclusion, prevention strategies should be tailored to the needs of male and female football players, with men more predisposed to hamstring strains and hip/groin injuries, and women to quadriceps strains and severe knee and ankle ligament injuries.

Longitudinal field test assessment in a Basque soccer youth academy: a multilevel modeling framework to partition effects of maturation.

The purpose of the study was to examine the effect of age on short-term performance indicators applying multilevel regression modeling, and whether changes induced by age were affected by maturation. The study applied a mixed longitudinal approach with 8 measurement points over a period of 4 years. Anthropometry, predicted adult stature, countermovement jump, 15-m sprint and agility test from 38 under-11 young soccer players were considered. Early maturing players were 3% taller compared to late maturers. A substantial effect of age was present in all performance indicators (P<0.05). Parameters showed improvements in performance, even when accounting for interindividual variation in somatic maturity. Vertical jump tended to be stable in early maturers during the first year, presenting an exponential increase thereafter (16%, P<0.05). Additionally, early maturing boys had lower vertical jump scores but a substantial higher rate of development with age (3% per year). Performance tends to plateau during the first 3 years following the improvements in agility (9.1%, P<0.05). In the running tests, early maturers had better performances (19%, P<0.05), while a higher rate of improvement of 1% was observed for the late maturers. Young soccer players should be expected to have substantial improvements in short-term performance, influenced by independent variation between players in maturity status.

Estudio del metabolismo glucolítico en jugadores de baloncesto / Gycolytic metabolism in basketball players

Introducción: El baloncesto desde un punto de vista energético, es clasificado en un 15 % aeróbico (Fox y Mathews 1984). Dalmonte (1987), justifica la importancia del metabolismo láctico en competición en 20 %. Sin embargo hay pocos estudios que evalúen la intervención de la glucólisis durante los partidos, además, sólo algunos de ellos utilizan jugadores jóvenes. Objetivo: Valorar el metabolismo glucolítico, mediante análisis de lactato plasmático durante la competición y estudiar su cinética en función del tiempo y puesto. Metodología: A 15 jugadores internacionales junior se les realizó muestras antes, durante y después del partido. Resultados: Los datos de concentración de lactato (LA) final son cercanos a 4 mmol/ (3,92 mMol/l), siendo el más alto de (5,30 mMol/l). Existen diferencias significativas entre períodos de juego, así como del base con respecto a los demás. No hemos observado relación entre el tiempo de juego y la concentración de lactato. Conclusión: El uso del metabolismo glucolítico, tanto aeróbico como anaeróbico, parece tener una importancia, en el baloncesto de alto nivel, mayor de la que se pensaba hasta ahora. Su estudio puede aportar información práctica para ajustar cargas de entrenamiento, conocer la situación metabólica durante el juego y diseño de estrategias nutricionales y de recuperación de la fatiga

Introduction: The basketball from an energetic point of view, is classified in 15 % aerobic (Fox y Mathews 1984), Dalmonte (1987), reported the major role of lactic metabolism during competition in 20 %. But there is a few studies to evaluate glycolytic metabolism during competition, and a few scientific evidence with young players. Objetive: To measure the glycolitic metabolism during the matches by plasmatic lactate concentration and study differences between periods and positions. Metodology: 15 internacional male basketball players participated in this study. Blood lactate testing was performed pre, per and post competition. Results: Our data present (3.92 mMol/l), the highest value was (5.30 mMol/l). There are significant differences between periods and there is not relation between playing time and (LA). Conclusion: The glycolytic metabolism, aerobic and anaerobic can be useful information to know the metabolic responses during the games, nutritional strategies and fatigue/recovery relation