Football and Urban Expansion in São Paulo,Brazil, 1880-1920

Football is central to Brazilian society, its way of imagining itself and its position in the world. Existing accounts of the origins of football in Brazil in the late nineteenth- and early twentieth-centuries tend towards mono-causal explanations, highlighting the role of British pioneers and Brazilian enthusiasm for the game. This article argues for a multi-causal explanation, using a mixed methodology of archival research in Brazil and the UK, combined with spatial analysis through the development of GIS maps. Building upon the existing interpretations, it shows how important the historical contexts of dynamics of urban expansion and transport infrastructure development – both with considerable British influence – were to the establishment of football as Brazil's national sport.     

Biomechanical characteristics of adults walking forward and backward in water at different stride frequencies

The aim of this study was to examine spatiotemporal characteristics and joint angles during forward and backward walking in water at low and high stride frequency. Eight healthy adults (22.1 ± 1.1 years) walked forward and backward underwater at low (50 pulses) and high frequency (80 pulses) at the xiphoid process level with arms crossed at the chest. The main differences observed were that the participants presented a greater speed (0.58 vs. 0.85 m/s) and more asymmetry of the step length (1.24 vs. 1.48) at high frequency whilst the stride and step length (0.84 vs. 0.7 m and 0.43 vs. 0.35 m, respectively) were lower compared to low frequency (P < 0.05). Support phase duration was higher at forward walking than backward walking (61.2 vs. 59.0%). At initial contact, we showed that during forward walking, the ankle and hip presented more flexion than during backward walking (ankle: 84.0 vs. 91.8º and hip: 22.8 vs. 8.0º; P < 0.001). At final stance, the knee and hip were more flexed at low frequency than at high frequency (knee: 150.0 vs. 157.0º and hip: ?12.2 vs. –14.5º; P < 0.001). The knee angle showed more flexion at forward walking (134.0º) than backward walking (173.1º) (P < 0.001). In conclusion, these results show how forward and backward walking in water at different frequencies differ and contribute to a better understanding of this activity in training and rehabilitation.     

Inter-participant variability in daily physical activity and sedentary time among male youth sport footballers: independent associations with indicators of adiposity and cardiorespiratory fitness

Participation in youth sport is assumed to promote and contribute towards more physically active lifestyles among children and adolescents. The aim of this study was to examine inter-participant variability in objectively measured habitual physical activity (PA) behaviours and sedentary time among youth sport participants and their implications for health. One-hundred-and-eighteen male youth sport footballers (Mean ± s = 11.72 ± 1.60) wore a GT3X accelerometer for 7 days. Average daily PA [min · day^?1, in light (LPA), moderate (MPA), vigorous (VPA) and combined moderate-to-vigorous (MVPA)] and sedentary time were calculated. Participants’ body mass index adjusted for age and sex (BMI–standard deviation score), per cent body fat (BF%), waist circumference and cardiorespiratory fitness were assessed. Results revealed that variability in daily PA behaviours and sedentary time (min · day^?1) was associated with BMI–standard deviation score [VPA (?), MVPA (?)], BF% [sedentary time (+), VPA (?), MVPA (?)], waist circumference [sedentary time (+), LPA (?)] and cardiorespiratory fitness [sedentary time (?), MPA (+), VPA (+), MVPA (+)]. Whilst sedentary time and MVPA were not related to health outcomes independent of one another, associations with markers of adiposity and cardiorespiratory fitness were stronger for sedentary time. Sedentary time was also significantly positively related to waist circumference independent of VPA. Results demonstrate inter-participant variability in habitual PA and sedentary time among youth sport participants which holds implications for their health. Thus, promoting PA and, in particular, reducing sedentary time may contribute towards the prevention of adverse health consequences associated with a physically inactive lifestyle for children and adolescents active in the youth sport context.     

The effect of 14 weeks of vitamin D3 supplementation on antimicrobial peptides and proteins in athletes

Heavy training is associated with increased respiratory infection risk and antimicrobial proteins are important in defence against oral and respiratory tract infections. We examined the effect of 14 weeks of vitamin D₃ supplementation (5000 IU/day) on the resting plasma cathelicidin concentration and the salivary secretion rates of secretory immunoglobulin A (SIgA), cathelicidin, lactoferrin and lysozyme in athletes during a winter training period. Blood and saliva were obtained at the start of the study from 39 healthy men who were randomly allocated to vitamin D₃ supplement or placebo. Blood samples were also collected at the end of the study; saliva samples were collected after 7 and 14 weeks. Plasma total 25(OH)D concentration increased by 130% in the vitamin D₃ group and decreased by 43% in the placebo group (both P = 0.001). The percentage change of plasma cathelicidin concentration in the vitamin D₃ group was higher than in the placebo group (P = 0.025). Only in the vitamin D₃ group, the saliva SIgA and cathelicidin secretion rates increased over time (both P = 0.03). A daily 5000 IU vitamin D₃ supplement has a beneficial effect in up-regulating the expression of SIgA and cathelicidin in athletes during a winter training period, which could improve resistance to respiratory infections.     

The acute testosterone,growth hormone,cortisol and interleukin-6 response to 164-km road cycling in a hot environment

This study investigated the acute endocrine responses to a 164-km road cycling event in a hot environment. Thirty-four male experienced cyclists (49.1 ± 8.3 years, 86.8 ± 12.5 kg, 178.1 ± 5.1 cm) participating in a 164-km road cycling event were recruited. Blood samples were collected within 0.3–2.0 h before the start (PRE: ~0500–0700 h) and immediately following the ride (POST). Samples were analysed for testosterone, growth hormone (GH), cortisol and interleukin-6 (IL-6). The temperature and humidity during the event were 35.3 ± 4.9°C and 47.2 ± 14.0%, respectively. Based on the finishing time, results for the fastest (FAST, 305 ± 10 min) and the slowest (SLOW, 467 ± 31 min) quartiles were compared. At POST, testosterone concentration was significantly (P < 0.05) lower (PRE, 20.8 ± 8.6; POST, 18.2 ± 6.7 nmol · L^?1), while GH (PRE, 0.3 ± 0.1; POST, 2.3 ± 0.3 µg · L^?1), cortisol (PRE, 661 ± 165; POST, 1073 ± 260 nmol · L^?1) and IL-6 (PRE, 4.0 ± 3.4; POST, 22.4 ± 15.2 pg · mL^?1) concentrations were significantly higher than those at PRE. At POST, GH and cortisol were significantly higher for the FAST group than for the SLOW group (GH, 3.6 ± 2.0 and 1.0 ± 0.8 µg · L^?1; cortisol, 1187 ± 209 and 867 ± 215 nmol · L^?1). Participation in an ultra-endurance road cycling event in a hot environment induced significant acute changes in concentrations of circulating hormones, with a greater augmentation of GH and cortisol in those completing the ride fastest.     

The key to success in elite athletes? Explicit and implicit motor learning in youth elite and non-elite soccer players

In sports, fast and accurate execution of movements is required. It has been shown that implicitly learned movements might be less vulnerable than explicitly learned movements to stressful and fast changing circumstances that exist at the elite sports level. The present study provides insight in explicit and implicit motor learning in youth soccer players with different expertise levels. Twenty-seven youth elite soccer players and 25 non-elite soccer players (aged 10–12) performed a serial reaction time task (SRTT). In the SRTT, one of the sequences must be learned explicitly, the other was implicitly learned. No main effect of group was found for implicit and explicit learning on mean reaction time (MRT) and accuracy. However, for MRT, an interaction was found between learning condition, learning phase and group. Analyses showed no group effects for the explicit learning condition, but youth elite soccer players showed better learning in the implicit learning condition. In particular, during implicit motor learning youth elite soccer showed faster MRTs in the early learning phase and earlier reached asymptote performance in terms of MRT. Present findings may be important for sports because children with superior implicit learning abilities in early learning phases may be able to learn more (durable) motor skills in a shorter time period as compared to other children.     

Effects of high-intensity interval training on cardiometabolic risk factors in overweight/obese women

The purpose of this study was to evaluate two practical interval training protocols on cardiorespiratory fitness, lipids and body composition in overweight/obese women. Thirty women (mean ± SD; weight: 88.1 ± 15.9 kg; BMI: 32.0 ± 6.0 kg · m²) were randomly assigned to ten 1-min high-intensity intervals (90%VO₂ peak, 1 min recovery) or five 2-min high-intensity intervals (80–100% VO₂ peak, 1 min recovery) or control. Peak oxygen uptake (VO₂ peak), peak power output (PPO), body composition and fasting blood lipids were evaluated before and after 3 weeks of training, completed 3 days per week. Results from ANCOVA analyses demonstrated no significant training group differences for any primary variables (P > 0.05). When training groups were collapsed, 1MIN and 2MIN resulted in a significant increase in PPO (?18.9 ± 8.5 watts; P = 0.014) and time to exhaustion (?55.1 ± 16.4 s; P = 0.001); non-significant increase in VO₂ peak (?2.36 ± 1.34 ml · kg^?1 · min^?1; P = 0.185); and a significant decrease in fat mass (FM) (??1.96 ± 0.99 kg; P = 0.011). Short-term interval exercise training may be effective for decreasing FM and improving exercise tolerance in overweight and obese women.     

Motorische Leistungsfähigkeit von Kindern und Jugendlichen in Deutschland

Motor performance is an important health resource. Review articles revealed a decline of motor performance of approximately 10?% between 1975 and 2006. In the past most of the data available for such comparisons came from ad hoc studies with non-standardized methods. Within the framework of the ”Motorik-Modul“ (MoMo) study as part of the German Health Interview and Examination Survey for Children and Adolescents (KiGGS), it is possible for the first time to directly compare two cohorts in the ages of 4–17 years in a nationally representative database for Germany. The aim of this article is to report changes in motor performance of children and adolescents in the time period 2003–2006 (cohort baseline n = 4528) compared to 2009–2012 (cohort wave 1, n = 2820). Overall, it is clearly shown that the motor performance of children and adolescents in Germany did not decrease within the observational period of 6 years. The comparison of mean values of the baseline cohort compared to those of wave 1 showed that 28 out of 52 mean values of the two cohorts with a high probability did not differ based on 95?% confidence intervals (CI). In 24 out of the 52 mean values positive changes could be noted based on the individual 95?% CI values. There were more positive changes in primary school aged children than in other age groups. Within these positive changes, most effect sizes were small to medium. The results indicate that recent activities aiming at elevating motor performance levels may have started to make an impact and should be expanded, also in secondary schools. The comparative cohort study presented in this article is currently being checked by the ongoing MoMo wave 2 survey of 2014–2017.