Effect of combined carbohydrate-protein ingestion on markers of recovery after simulated rugby union match-play

Abstract

In this study, we investigated the effect of ingesting carbohydrate alone or carbohydrate with protein on functional and metabolic markers of recovery from a rugby union-specific shuttle running protocol. On three occasions, at least one week apart in a counterbalanced order, nine experienced male rugby union forwards ingested placebo, carbohydrate (1.2 g · kg body mass^?1 · h^?1) or carbohydrate with protein (0.4 g · kg body mass^?1 · h^?1) before, during, and after a rugby union-specific protocol. Markers of muscle damage (creatine kinase: before, 258 ± 171 U · L^?1 vs. 24 h after, 574 ± 285 U · L^?1; myoglobin: pre, 50 ± 18 vs. immediately after, 210 ± 84 nmol · L^?1; P < 0.05) and muscle soreness (1, 2, and 3 [maximum soreness = 8] for before, immediately after, and 24 h after exercise, respectively) increased. Leg strength and repeated 6-s cycle sprint mean power were slightly reduced after exercise (93% and 95% of pre-exercise values, respectively; P < 0.05), but were almost fully recovered after 24 h (97% and 99% of pre-exercise values, respectively). There were no differences between trials for any measure. These results indicate that in experienced rugby players, the small degree of muscle damage and reduction in function induced by the exercise protocol were not attenuated by the ingestion of carbohydrate and protein.     

A bioecological perspective on talent identification in junior-elite soccer: A Pan-European perspective

ABSTRACT

Elite soccer clubs across Europe spend ever-increasing sums of money on transfers and salaries for world-class players. Consequently, clubs’ talent identification and development processes for junior players have become more professionalised. Based on a holistic ecological approach, this study presents an analysis of talent identification practices across some of the most productive soccer academies in Europe (N = 11). Data were collected via semi-structured interviews with 11 heads of academy recruitment from clubs in the “big five” European leagues. Clubs were purposively sampled based on their player productivity ranking. Interviews ranged from 52:26 minutes to 114:06 minutes in length (m = 87:53 ± 20.10 minutes). This study argues that holistic ecological approaches the environments were characterised through the interplay of factors that ranged from high-level internal to international level relationships. This resulted in the identification and recruitment of players from local and international environments. The purpose of recruitment was suggested to have a dual purpose: recruitment of players for the first team; recruitment of players for further development/monitoring and/or selling to another club.     

Effect of tennis racket parameters on a simulated groundstroke

Composite materials have given manufacturers the freedom to develop a broad range of tennis rackets, allowing them to change key parameters such as the structural stiffness, mass, and position of the balance point. The aim of this research was to determine how changing these parameters could affect ball resultant rebound velocity and spin for a simulated groundstroke. A finite element model of a freely suspended racket and strings was used to determine the effect of racket parameters for oblique spinning impacts at a range of locations on the stringbed. The finite element simulations were conducted in the laboratory frame of reference, where the ball is projected onto an initially stationary racket. The mean rebound velocity of the ball was 9% higher for a structurally stiff racket, 37% higher for a heavy racket, and 32% higher for a head-heavy racket. In addition, the mean rebound topspin of the ball was 23% higher for a heavy racket and 21% higher for a head-heavy racket. Therefore, in relation to a groundstroke with an impact location away from the node, the rebound velocity of the ball is likely to increase with the structural stiffness of a racket. The effect of changing the mass and position of the balance point is more complex, as it is dependent on the relationship between the transverse moment of inertia and maximum pre-impact swing velocity.     

Health Education Needs of High School Students in a Large Diversified Metropolitan Area

Abstract

In addition to the findings of related studies, four sources of information were selected as a basis for determining the health education needs of high school students. Data were obtained from a representative sample of 959 B10 and A12 grade students in eight Los Angeles high schools by use of the LeMaistre Health Behavior Inventory, the Mooney Problem Check List, information derived from appraisals by school physicians' examinations, and personal data questionnaires on health history which students were asked to complete. The LeMaistre Inventory showed greatest weaknesses to be in the health education areas of sleep, rest, and relaxation; prevention and control of chronic and degenerative diseases; safety education; and consumer health. The Mooney Check List showed most student concerns to be in the areas of sleep, rest, and relaxation; mental health; personal health; and nutrition. From the physicians' examinations, orthopedic, dental, visual, and skin defects were observed most frequently; these findings have implications for the instructional areas of personal health and dental health. From student personal health histories, nutrition; consumer health; sleep, rest, and relaxation; and stimulants and depressants were evident as the instructional areas needing greatest emphasis.

Although little or no statistically significant relationship was found among students' scores on the various techniques which were used to identify needs, it was possible to note an interrelationship among the rank order of certain areas. Moreover, statistically significant grade and sex differences (.05) were apparent in certain aspects of students' health behavior.     

Friendships Over the Transition from Early Childhood Centre to School Les Aities au Cours de la transition entre le Centre d'Enseignement Prescolaire et l'Ecole Primaire Amistades en el Periodo de Transicion de los Centros de Primera Infancia a la Escuela

This study is an ethnographic, participant observation study of the friendships of 16 4-5-year-old children over the transition to school. Data were collected over 18 months through regular visits with children at kindergarten, home and school. Children were followed individually by the researcher on the first day of school. Anecdotal field notes and videotaped interviews were analysed according to friendship themes. Children played, shared activities and fun together with friends. Important shared activities for friends over the transition included birthday parties and associated gift giving, staying overnight, sharing resources (for example toys or pens) and involvement in reciprocal or complementary play. Children viewed the researcher as a friend: they played with her, asked for her help, joined in activities with her and gained comfort from her proximity. Only two dyadic friendships survived over the transition to school. While friendships were a focal concern of children's lives during the transition, children with friends did not make an easier transition to school. C'est une etude sur les amities de seize enfants, ages de 4 a 5 ans, durant leur transition de l'ecole maternelle a l'ecole. La methodologie consiste de l'observation participante du domaine ethnographique. Les donnees ont rassemble pendant 18 mois par des visitees regulieres aux ecoles maternelle, aux ecoles et chez les enfants. Chaque enfant etait accompagne par la chercheuse la premiere journee a l'ecole. Les annotations anecdotiques et les entrevues enregistres sur magnetoscope, etaient analyses selon des themes sur l'amitie. Les enfants ont joue, ils se sont bien s'amuses avec leurs amis et ils ont partage aux activites ensemble, comme des fetes d'anniversaire complet avec les cadeaux d'anniversaire, ils se sont passes la nuit chez l'un l'autre, ils se sont partages les choses (comme des jouets et des plumes) et ils se sont engages dans des jeux muteuls et complementaires. Les enfants voyaient la chercheuse comme une amie-ils ont joue avec elle, ont demande son aide, ont partage aux activites avec elle et ils l'ont trouvee une consolanteuse. Il' n'y avait que deux pairs des amis qui ont survecu la transition a l'ecole. Bien que les amities aient une place centrale dans la vie des enfants pendant la transition, ceux qui avaient leurs amis n'avaient pas une transition plus facile. Este es un estudio etnografico y participe-observacion de las amistades de 16 ninos/ninas de 5-6 anos durante la transicion hacia la escuela. Datos fueron recolectados durante 18 meses atraves the visitas regulares al parvulario, al hogar y a la escuela. Los ninos fueron observados individualmente por la investigadora en el primer dia de escuela. Notas anecdoticas y entrevistas video-grabadas fueron analisados de acuerdo a temas de amistad. Los ninos jugaban, compartian actividades y se divertian juntos. Las actividades compartidas importante para los amigos durante la transicion incluyian las fiestas de cumpleanos y regalos, el pasar la noche, el compartir recursos (como juguetes y lapiceros), y el envolvimiento en juegos reciprocos o complementarios. Los ninos veian a la como amigajugaban con ella, solicitaban su ayuda, se unian en actividades con ella y se comfortaban con su proximidad. Solamente dos amistadas diadicas sobrevivieron la transicion hacia la escuela. Aunque las amistades eran una proeucupacion focal en la vida de los ninos durante la transicion los ninos con amigos no tuvieron una transicion mas facil.