Prediction of sports talent in young throwers using machine learning / Predicción del talento deportivo en jóvenes lanzadores utilizando machine learning

The objective of this study is to detect any performance factors in athletics throws between 1997 and 2015 in 662 throwers (15.67 ± 1.01 years of the National Program for Sports Technification of the Royal Spanish Athletics Federation using Machine Learning methods by means of algorithms (Logistic Regression, Random Forest and XG Boost). When examining the importance of the variables with reference to performance, the triple jump (0.20) stands out over the rest of the variables: backward overhead shot throw (0.14), arm span (0.11), vertical jump (0.10), body mass (0.20), height (0.07) and flexibility (0.03). In each discipline the triple jump takes the lead in shot put (0.20), discus (0.21) and hammer (0.29) throws, while backward overhead shot throw does in javelin, the variables rearranging themselves in a particular way depending on the discipline. These findings enable the early detection of potential talents as well as their subsequent sport specialization (AU)

El estudio aborda la detección de factores de rendimiento en los lanzamientos atléticos utilizando técnicas de Machine Learning, en 662 lanzadores (15,67 ± 1,01 años) del Programa Nacional de Tecnificación Deportiva de la Real Federación Española de Atletismo entre 1997 y 2015, mediante diferentes algoritmos (Logistic Regression, Random Forest y XGBoost). Al medir la importancia de las variables en función del rendimiento, el triple salto (0,20) destaca sobre el resto de variables: lanzamiento dorsal (0,14), envergadura (0,11), salto vertical (0,10), masa corporal, estatura (0,07) y flexibilidad (0,03). En cada disciplina, el triple salto encabeza la importancia en los lanzamientos de peso (0,20), disco (0,21) y martillo (0,29), mientras que el lanzamiento dorsal lo hace en la jabalina (0,20). Las variables se reordenande forma particular modificando su importancia para cada disciplina. Estos hallazgos permiten mejorar la detección inicial de posibles talentos, así como su posterior especialización deportiva (AU)

Effects of plyometric training on explosive strength, acceleration capacity and kicking speed in young elite soccer players.

AIM: The main aim of this study was to determine the effects of a 10-week plyometric training program on explosive strength, acceleration capacity and kicking speed in young elite soccer players. METHODS: Twenty-two players participated in the study: control group (CG), (N.=11; 18.2 ± 0.9 years) and treatment group (TG) (N.=11; 18.4 ± 1.1 years). Both groups performed technical and tactical training exercises and matches together. However, the CG players followed the regular physical conditioning program, which was replaced by a plyometric program for TG. Plyometric training took place three days a week and included jumps over hurdles, horizontal jumps and lateral jumps over hurdles. Jumping ability, 10 m sprint and kicking speed were measured on five separate occasions. RESULTS: Two-way analysis of variance (ANOVA) with repeated measures reflected that the TG demonstrated significant increases (P<0.05) in jumping ability and acceleration capacity after six weeks of training and in kicking speed with dominant and non-dominant leg after eight and ten weeks respectively. On the other hand there were no significant changes in CG players throughout the study. CONCLUSION: The main findings revealed that a 10-week plyometric program may be an effective training stimulus to improve explosive strength compared to a more conventional physical training program. The improvements in explosive strength can be transferred to acceleration capacity and kicking speed but players need time to transfer these increases.

Anthropometric and anaerobic fitness profile of elite and non-elite female soccer players.

AIM: The main aim of the current study was to compare the anthropometrical and fitness profile of female soccer players by level and by playing positions. The second purpose was to explore correlations between kicking speed on the one hand and anthropometric features and explosive strength on the other. METHODS: Female soccer players (N.=190) were tested divided in two groups: elite group (N.=100) and non-elite group (N.=90). Body mass, height, leg length, body composition, counter movement jump, drop jump and kicking speed with both legs were measured. RESULTS: After controlling for experience with multivariate analysis of covariance (MANCOVA), body mass, body fat and muscle mass differed significantly by level. MANCOVA also revealed that all the anthropometrical variables differed by playing position. However, MANCOVA did not show significant differences by level of play, neither for explosive strength nor for kicking speed but revealed significant differences among playing positions. There were significant positive correlations between body mass, height, leg length, muscle mass, counter movement jump height, drop jump height and experience on the one hand and kicking speed with dominant and non-dominant leg on the other for the elite and non-elite players. CONCLUSIONS: Elite players differ from their non-elite counterparts in terms of anthropometrical features, while explosive strength and kicking speed are not sensitive enough to distinguish between levels. On the other hand, the findings indicate few positional variations, and only goalkeepers, tend to have a specific anthropometric and fitness profile. Anthropometric variables, explosive strength and experience have an influence on kicking speed.

[Optic nerve hypoplasia associated to ectopic neurohypophysis]. / Hipoplasia del nervio optico asociada a neurohipófisis ectópica.

Hypoplasia of the optic nerve is a rare congenital anomaly of unknown etiology that is a frequent cause of blindness in children. It can present in isolation or associated to other malformations of the central nervous system. Magnetic resonance is the technique of choice for the study of this condition; it enables both the hypoplasia of the nerve and the possible associated malformations to be demonstrated. We present a case of optic nerve hypoplasia associated to ectopic neurohypophysis.

Vanadyl sulfate improves hepatic and muscle insulin sensitivity in type 2 diabetes.

Vanadyl sulfate (VOSO(4)) is an oxidative form of vanadium that in vitro and in animal models of diabetes has been shown to reduce hyperglycemia and insulin resistance. Small clinical studies of 2- to 4-week duration in type 2 diabetes (T2DM) have led to inconsistent results. To define its efficacy and mechanism of action, 11 type 2 diabetic patients were treated with VOSO(4) at a higher dose (150 mg/day) and for a longer period of time (6 weeks) than in previous studies. Before and after treatment we measured insulin secretion during an oral glucose tolerance test, and endogenous glucose production (EGP) and whole body insulin-mediated glucose disposal using the euglycemic insulin clamp technique combined [3-(3)H]glucose infusion. Treatment significantly improved glycemic control: fasting plasma glucose (FPG) decreased from 194 +/- 16 to 155 +/- 15 mg/dL, hemoglobin A(1c) decreased from 8.1 +/- 0.4 to 7.6 +/- 0.4%, and fructosamine decreased from 348 +/- 26 to 293 +/- 12 micromol/L (all P < 0.01) without any change in body weight. Diabetics had an increased rate of EGP compared with nondiabetic controls (4.1 +/- 0.2 vs. 2.7 +/- 0.2 mg/kg lean body mass.min; P< 0.001), which was closely correlated with FPG (r = 0.56; P< 0.006). Vanadyl sulfate reduced EGP by about 20% (P< 0.01), and the decline in EGP was correlated with the reduction in FPG (r = 0.60; P< 0.05). Vanadyl sulfate also caused a modest increase in insulin-mediated glucose disposal (from 4.3 +/- 0.4 to 5.1 +/- 0.6 mg/kg lean body mass x min; P< 0.03), although the improvement in insulin sensitivity did not correlate with the decline in FPG after treatment (r = -0.16; P = NS). Vanadyl sulfate treatment lowered the plasma total cholesterol (223 +/- 14 vs. 202 +/- 16 mg/dL; P < 0.01) and low density lipoprotein cholesterol (141 +/- 14 vs. 129 +/- 14 mg/dL; P < 0.05), whereas 24-h ambulatory blood pressure was unaltered. We conclude that VOSO(4) at maximal tolerated doses for 6 weeks improves hepatic and muscle insulin sensitivity in T2DM. The glucose-lowering effect of VOSO(4) correlated well with the reduction in EGP, but not with insulin-mediated glucose disposal, suggesting that liver, rather than muscle, is the primary target of VOSO(4) action at therapeutic doses in T2DM.