The effects of an increased calorie breakfast consumed prior to simulated match-play in Academy soccer players

Dietary analysis of Academy soccer players highlights that total energy and carbohydrate intakes are less than optimal, especially, on match-days. As UK Academy matches predominantly kick-off at ～11:00?h, breakfast is likely the last pre-exercise meal and thus may provide an intervention opportunity on match-day. Accordingly, the physiological and performance effects of an increased calorie breakfast consumed ～135-min before soccer-specific exercise was investigated. English Premier League Academy soccer players (n?=?7) repeated a 90-min soccer match simulation on two occasions after consumption of habitual (B_hab; ～1100?kJ) or increased (B_inc; ～2100?kJ) energy breakfasts standardised for macronutrient contributions (～60% carbohydrates, ～15% proteins and ～25% fats). Countermovement jump height, sprint velocities (15-m and 30-m), 30-m repeated sprint maintenance, gut fullness, abdominal discomfort and soccer dribbling performances were measured. Blood samples were taken at rest, pre-exercise, half-time and every 15-min during exercise. Although dribbling precision (P?=?.522; 29.9?±?5.5?cm) and success (P?=?.505; 94?±?8%) were unchanged throughout all time-points, mean dribbling speed was faster (4.3?±?5.7%) in B_inc relative to B_hab (P?=?.023; 2.84 vs 2.75?m?s^?1). Greater feelings of gut fullness (67?±?17%, P?=?.001) were observed in B_inc without changes in abdominal discomfort (P?=?.595). All other physical performance measures and blood lactate and glucose concentrations were comparable between trials (all P?>?.05). Findings demonstrate that Academy soccer players were able to increase pre-match energy intake without experiencing abdominal discomfort; thus, likely contributing to the amelioration of energy deficits on match-days. Furthermore, whilst B_inc produced limited benefits to physical performance, increased dribbling speed was identified, which may be of benefit to match-play.     

Antioxidant-rich beetroot juice does not adversely affect acute neuromuscular adaptation following eccentric exercise

This study examined the effects of beetroot juice on the repeated bout effect (RBE) to eccentric exercise. Twenty-nine recreationally active males performed two bouts of 100-drop jumps, separated by 14–21 days. Using a double-blind, independent groups design, participants consumed either a higher dose beetroot juice (H-BT; 250 ml, n = 10), a lower dose beetroot juice (L-BT; 125 ml, n = 9) or an isocaloric placebo (PLA; 250 ml, n = 10) for 3 days after bout 1; no drinks were consumed after bout 2. Maximal isometric voluntary contraction (MIVC), countermovement jump (CMJ), pressure-pain threshold (PPT) and creatine kinase (CK) were measured pre, post, 24, 48 and 72 h following both bouts. In bout 2, CMJ and MIVC recovered quicker and CK activity was attenuated (versus bout 1) (P < 0.05) in all groups, demonstrating an RBE. At 24 h post bout 1, MIVC was 84.1 ± 16.1, 83.6 ± 11.6, 79.7 ± 15.1% relative to baseline values in the H-BT, L-BT and PLA groups, respectively; at 24 h post bout 2, MIVC recovered to 90.7 ± 13.7, 92.9 ± 6.9, 87.8 ± 6.9, in the H-BT, L-BT and PLA groups, respectively. These findings suggest that supplementation with antioxidant-rich beetroot juice does not adversely affect acute adaptations to a bout of eccentric exercise.     

Role Fulfillment Mediates the Association Between Daily Family Assistance and Cortisol Awakening Response in Adolescents

Family assistance (helping the family) is associated with both positive and negative psychological and biological outcomes during adolescence. However, the association between family assistance and the hypothalamic–pituitary–adrenal (HPA) axis remains unstudied. Thus, we assess how helping the family relates to adolescents’ diurnal cortisol, an index of HPA activity, and psychological outcomes. Three hundred and seventy ethnically diverse adolescents (ages 11–18) reported daily helping behaviors and psychological experiences for 14 days and provided four saliva samples per day for 4 days. Multilevel modeling revealed that cortisol awakening response was lower the day after adolescents helped their families more. This association was explained, in part, by perceived role fulfillment (feeling like a good son, daughter, and sibling). Results highlight a possible psychological and biological benefit of assisting the family during adolescence.     

Associations Between Perceived Material Deprivation,Parents’ Discipline Practices,and Children's Behavior Problems: An International Perspective

This study investigated the association between perceived material deprivation, children's behavior problems, and parents’ disciplinary practices. The sample included 1,418 8- to 12-year-old children and their parents in China, Colombia, Italy, Jordan, Kenya, the Philippines, Sweden, Thailand, and the United States. Multilevel mixed- and fixed-effects regression models found that, even when income remained stable, perceived material deprivation was associated with children's externalizing behavior problems and parents’ psychological aggression. Parents’ disciplinary practices mediated a small share of the association between perceived material deprivation and children's behavior problems. There were no differences in these associations between mothers and fathers or between high- and low- and middle-income countries. These results suggest that material deprivation likely influences children's outcomes at any income level.     

Multidisciplinary predictors of adherence to contemporary dance training: findings from the UK Centres for Advanced Training

Little is known about the predictors of adherence in a dance context. The aim of this study was to investigate adherence to a dance talent programme using a multidisciplinary set of variables representing psychological correlates of adherence, maturation and physical factors relating to dance talent. Psychological (passion, motivational climate perceptions, eating attitudes), physical competence (vertical jump height, handgrip strength, hamstring flexibility, external hip rotation, aerobic fitness), and maturation-related (age of menarche) variables were gathered from female students enrolled on a dance talent programme. Participation behaviour (adherence/dropout) was collected from the talent programme’s records approximately two years later. Logistic regression analysis of 287 participants revealed that greater levels of harmonious passion predicted greater likelihood of adherence to the programme, and greater ego-involving motivational climate perceptions predicted less likelihood of adherence. Neither measures of physical competence nor maturation distinguished adhering from dropout participants. Overall, the results of this study indicate that psychological factors are more important than physical competence and maturation in the participation behaviour of young talented dancers.     

‘Strong is the new skinny’: navigating fitness hype among teenagers in northern Sweden

An increased interest in health, diet, and physical activity exist among young people, in this study termed ‘fitness hype’. Viewing the body and health as commodities can be understood as part of a healthism discourse. In this study, we explored how Swedish high school students perceive and negotiate the trend regarding exercise, diet and body ideals. Semi-structured interviews were conducted with ten high school students, aged 16–18 years, from various educational programs and with varying levels of physical activity. Using qualitative content analysis, we developd one overarching theme navigating life satisfaction in the face of an ‘unhealthy fitness hype’. Four additional, interrelated categories showed how the young people negotiated this developing trend through: (1) the quest for social recognition and value, (2) social media sets the standards, (3) the paradox of strong and skinny as the new standard, and (4) the need for new safety nets. Our results highlight the young people’s perceptions of an excessive and influential focus on health and exercise in contemporary society. They described a fitness hype as exorbitant and unhealthy ideals of body and exercise, and understood this as problematic. Social media was seen as contributing to this hype as a powerful arena for ‘the quest for social recognition and value’. While not all the young people felt negatively affected by the fitness hype, they perceived its influence on their lives. Further, body and fitness ideals were gendered. Teenage girls faced the paradox of shaping themselves as ‘strong and skinny’. Social ties were recognized as an important safety net, particularly classmates, sports mates, and coaches. Knowledge of these problems from the perspective of young people is crucially needed among health professionals and educators. Further research should explore additional support strategies, and young people’s experiences of fitness hype among additional youth groups.     

Study of silica nanoparticles – polysiloxane hydrophobic treatments for stone-based monument protection

The growing interest in the conservation of historic buildings encourages the development of water-repellent materials and methodologies to consolidate and/or protect stones. Recently, particular attention was devoted to composites of inorganic oxides nanoparticles and hybrid siloxane or silicone polymers. Here we present a study on the water repellence of a thin protective coating obtained through sol-gel process starting from Glymo and Dynasylan 40®, and loading the silicate matrix with nano-sized silica particles (Aeroxide LE1® -Degussa-Evonik). The coatings were applied to limestone, sandstone and granite samples. The silica nanoparticles have been characterized by XRD, the siloxane matrix through micro-Raman spectroscopy, while the surface morphology was examined by SEM. The efficacy of the treatments has been evaluated through static contact angle measurements and capillary water absorption. The optical appearance of the coatings was evaluated by colorimetric measurements. Nanoparticles at suitable concentration gave high values for the static contact angle (up to ∼ 150°), for all stone species even for four months exposure to atmospheric conditions. The coatings, in the water capillary absorption tests, however, behave as expected only for granite even if the long-term water direct contact reduces the hydrophobicity.     

Consistency of performances in the Tkatchev release and re-grasp on high bar

The Tkatchev on the high bar is a release and re-grasp skill in which the gymnast rotates in a direction during flight opposite to that of the preceding swing. Since the release window is defined as the time during which the gymnast has appropriate linear and angular momentum to ensure the bar can be re-grasped, it was speculated that the release windows for this skill would be smaller than for dismounts that are less constrained. One senior male gymnast competing at national standard performed 60 Tkatchev trials. A four-segment planar simulation model of the gymnast and high bar was used to determine the release windows in 10 successful and 10 unsuccessful performances of the Tkatchev recorded using a Vicon motion analysis system. Model parameters were optimized to obtain a close match between simulations and recorded performances in terms of rotation angle (1 degree), bar displacements (0.01 m), and release velocities (1%). Each matched simulation was used to determine the time window around the actual point of release for which the model had appropriate release parameters to complete the Tkatchev successfully. The release windows for the successful trials were small compared with those of dismounts. The unsuccessful trials were associated with later release and later timing of the actions at the shoulders and hips.     

Différentes représentations utilisant la notion de barycentre

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