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Purpose: To compare mechanical properties of overground sprint running in elite rugby union and rugby league athletes. Methods: Thirty elite rugby code (15 rugby union and 15 rugby league) athletes participated in this cross-sectional analysis. Radar was used to measure maximal overground sprint performance over 20 or 30 m (forwards and backs, respectively). In addition to time at 2, 5, 10, 20, and 30 m, velocity-time signals were analyzed to derive external horizontal force--velocity relationships with a recently validated method. From this relationship, the maximal theoretical velocity, external relative and absolute horizontal force, horizontal power, and optimal horizontal force for peak power production were determined. Results: While differences in maximal velocity were unclear between codes, rugby union backs produced moderately faster split times, with the most substantial differences occurring at 2 and 5 m (ES 0.95 and 0.86, respectively). In addition, rugby union backs produced moderately larger relative horizontal force, optimal force, and peak power capabilities than rugby league backs (ES 0.73-0.77). Rugby union forwards had a higher absolute force (ES 0.77) despite having ~12% more body weight than rugby league forwards. Conclusions: In this elite sample, rugby union athletes typically displayed greater short-distance sprint performance, which may be linked to an ability to generate high levels of horizontal force and power. The acceleration characteristics presented in this study could be a result of the individual movement and positional demands of each code. [ABSTRACT FROM AUTHOR]

ABSTRACT: BACKGROUND: While dietary sources of calcium are important for bone health, the intake of milk and milk products decreases as children get older. A free milk in schools program may mitigate this decrease in milk consumption. We evaluated the Fonterra Milk for schools program (a free milk initiative) by determining changes in children's milk consumption and anthropometric measures over a 2‐year period. METHODS: The evaluation was conducted in children aged 7‐9 years in a representative sample of primary schools participating in the free milk program, in Auckland, New Zealand. The primary outcome was the proportion of children meeting the New Zealand guidelines for dairy and milk product consumption over 7 days (≥2 servings per day). Changes in anthropometric measures were also assessed as secondary outcomes. RESULTS: Nine schools (N = 511 children) participated in the evaluation. The proportion of children meeting the New Zealand guidelines for milk and milk product consumption over 7 days increased significantly from baseline to 2 years' follow‐up (72% vs 94%; p < .001). Body mass index z scores did not change significantly between baseline and 2 years' follow‐up. CONCLUSIONS: The Fonterra Milk for Schools initiative appears to be an effective way of increasing milk/milk product consumption behaviors in school‐aged children. [ABSTRACT FROM AUTHOR]

Children born small for gestational age (SGA) have an increased risk of cardiovascular disease (CVD) and associated risk factors in later life; however, little is known about their dietary intakes. The objective of this study was to assess dietary intakes in SGA and appropriate for gestational age (AGA) at 3.5, 7, and 11 years. The Auckland Birthweight Collaborative Study is a longitudinal case-control study of children born at term ( n = 871). Children were assessed at 3.5 ( n = 550), 7 ( n = 591), and 11 ( n = 620) years of age. Diet was assessed using a 24-hr record-assisted recall. Reported dietary intakes were analyzed and compared with the Australian and New Zealand Nutrient Reference Values. Compared with AGA, median energy intakes were significantly lower in SGA at 3.5 years (4.2 MJ [IQR, 3.0 to 5.8] vs. 5.4 MJ [IQR, 3.9 to 6.5]; p < .0001) but not at 7 and 11 years. Inadequate dietary intakes of micronutrients were more prevalent among SGA at 3.5 years and 11 years of age. A large proportion of SGA and AGA children consumed more than the recommended amounts of saturated fats, sugars, and sodium. There was no association of dietary intake and socio-demographic factors. This study reveals that dietary intake in 3.5-year-old children born SGA is lower in energy and a variety of micronutrients compared with dietary intake in AGA. These intakes may however be appropriate given their BMI z-scores. High intakes of sodium, saturated fat, and sugars are a concern for all children in this cohort. [ABSTRACT FROM AUTHOR]

This study compared the effects of six warm-up modalities on peak power output (PPO) during the high-pull exercise. Nine resistance-trained males completed six trials using different warm-ups: highpull specific (HPS), cycle, whole body vibration (WBV), cycle+HPS, WBV+HPS and a control. Intramuscular temperature (Tm) was increased by 2°C using WBV or cycling. PPO, Tm and electromyography (EMG) were recorded during each trial. Two high-pulls were performed prior to and 3 min after participants completed the warm-up. The greatest increase in PPO occurred with HPS (232.8 ± 89.7 W, P < 0.001); however, this was not different to combined warm-ups (cycle+HPS 158.6 ± 121.1 W; WBV +HPS 177.3 ± 93.3 W, P = 1.00). These modalities increased PPO to a greater extent than those that did not involve HPS (all P < 0.05). HPS took the shortest time to complete, compared to the other conditions (P < 0.05). EMG did not differ from pre to post warm-up or between modalities in any of the muscles investigated. No change in Tm occurred in warm-ups that did not include cycling or WBV. These results suggest that a movement-specific warm-up improves performance more than temperature- related warm-ups. Therefore, mechanisms other than increased muscle temperature and activation may be important for improving short-term PPO. [ABSTRACT FROM AUTHOR]

STUDY DESIGN: Feasibility randomized controlled trial. OBJECTIVES: To assess the feasibility of a trial to investigate the effectiveness of a lumbopelvic monitor as a feedback device for modifying postural behavior during daily work-related activities, BACKGROUND: Frequent or sustained flexed postures play a role in the development or maintenance of nonspecific low back pain. The provision of postural feedback could help individuals with or at risk of nonspecific low back pain improve their postural awareness and avoid hazardous or pain-provoking postures. METHODS: Sixty-two participants employed in a health care organization were randomly allocated into 1 of 3 groups: a control group, an intermittent feedback group, and a constant feedback group. Adherence and follow-up rates were assessed. Differences in postural pattern between baseline and follow-up measurements were used to assess the effectiveness of the lumbopelvic monitor as a postural feedback device, RESULTS: Adherence was approximately 75%. With the exception of 1 center, the follow-up overall rates exceeded the a priori desired threshold of 80%. Within-group comparisons revealed no significant differences in postural pattern for the control group and intermittent feedback group. The constant feedback group showed a significant reduction in flexed posture at the follow-up period compared with the baseline period. Differences between groups did not reach statistical significance; however, the constant feedback group, compared with the control group, demonstrated an effect size (d) of 0.60. CONCLUSION: The provision of constant postural feedback seems promising for promoting changes in postural behavior. This feasibility trial identified adherence and follow-up rates and sample-size estimates important to the conduct of a fully powered efficacy trial. LEVEL OF EVIDENCE: Therapy, level 2b-. [ABSTRACT FROM AUTHOR]

The aim of the study was to validate the self-report Multimedia Activity Recall for Children and Adolescents (MARCA) against accelerometry for the assessment of physical activity in New Zealand children. Participants (n = 716, 10–18 years) recalled 3–4 days of activity using the MARCA and underwent a partially overlapping 7-day accelerometry protocol during a national survey. Spearman correlation coefficients (ρ) assessed the association between accelerometer-derived counts per minute and MARCA-derived physical activity level and time in locomotion. Both data sources estimated time spent in light and moderate–vigorous physical activity. Association and agreement between methods for light physical activity and moderate–vigorous physical activity was assessed using correlations and Bland–Altman plots respectively, and pairedt-tests conducted. Accelerometer-derived activity counts were moderately correlated with both MARCA-derived physical activity level and locomotion (ρ = 0.38,P < 0.0001). The correlation between methods was –0.14 for light physical activity and 0.28 for moderate–vigorous physical activity (P < 0.0001). The MARCA overestimated moderate–vigorous physical activity compared with accelerometry (120 min,P < 0.0001), which increased as moderate–vigorous physical activity time increased. Some sex and ethnicity (Māori [indigenous] versus non-Māori) differences were observed. Overall, the MARCA indicated moderate validity for assessment of physical activity level, locomotion and moderate–vigorous physical activity and poor validity for assessment of light physical activity. This was comparable to other self-report tools. The MARCA has utility for future large-scale research. [ABSTRACT FROM PUBLISHER]

Background: Vitamin C (ascorbate) is likely to be essential for skeletal muscle structure and function via its role as an enzyme cofactor for collagen and carnitine biosynthesis. Vitamin C may also protect these metabolically active cells from oxidative stress. Objective: We investigated the bioavailability of vitamin C to human skeletal muscle in relation to dietary intake and plasma concentrations and compared this relation with ascorbate uptake by leukocytes. Design: Thirty-six nonsmoking men were randomly assigned to receive 6 wk of 0.5 or 2 kiwifruit/d, an outstanding dietary source of vitamin C. Fasting blood samples were drawn weekly, and 24-h urine and leukocyte samples were collected before intervention, after intervention, and after washout. Needle biopsies of skeletal muscle (vastus lateralis) were carried out before and after intervention. Results: Baseline vastus lateralis ascorbate concentrations were ~16 nmol/g tissue. After intervention with 0.5 or 2 kiwifruit/d, these concentrations increased 3.5-fold to 53 and 61 nmol/g, respectively. There was no significant difference between the responses of the 2 groups. Mononuclear cell and neutrophil ascorbate concentrations increased only ~1.5- and ~2-fold, respectively. Muscle ascorbate concentrations were highly correlated (P < 0.001) with dietary intake (R = 0.61) and plasma concentrations (R = 0.75) in the range from 5 to 80 μmol/L. Conclusions: Human skeletal muscle is highly responsive to vitamin C intake and plasma concentrations and exhibits a greater relative uptake of ascorbate than leukocytes. Thus, muscle appears to comprise a relatively labile pool of ascorbate and is likely to be prone to ascorbate depletion with inadequate dietary intake. [ABSTRACT FROM AUTHOR]

The article discusses research which was conducted to investigate whether wearing compression garments during recovery improved subsequent repeated sprint and three kilometer run performance in rugby players. Researchers evaluated 22 players. They found that wearing compressive garments during recovery was likely to be worthwhile, and very unlikely to be harmful for well trained rugby players.

Background: Reduced time dedicated to physical education and free play in recent decades emphasizes the need to promote opportunities for sport participation in adolescents in order to increase physical activity levels. The purpose of this study was to examine the association of sociodemographic and biological characteristics, behavioural patterns, and school-related and sport-specific variables with time spent participating in sport. Methods: A total of 1837 secondary school students (age: 14.6 ± 1.2 years; 50.9 % boys) from 19 of 23 schools in the Otago Region (New Zealand) completed an online sport survey and Youth Physical Activity Questionnaire in 2009. Using multilevel modeling, we examined the association of individual-, school- and sport-related variables on sport participation and the amount of time spent in sports. Results: Higher rates of sport participation were associated with lower neighbourhood deprivation scores (OR (95% CI): 0.75 (0.49-1.14), 0.57 (0.38-0.86), 0.48 (0.28-0.81)), higher quintiles of physical activity (2.89 (2.10-3.96), 2.81 (1.68- 4.70), 3.54 (2.24-5.57), 3.97 (1.99-7.95)), highest quintiles of screen time (1.58 (0.94-2.65), 1.99 (1.42-2.80), 2.17 (1.43- 3.30), 1.88 (1.37-2.57)) and boys only school status (2.21 (1.57-3.10)). Greater amount of time spent in sports was associated with male gender (0.56 (0.43-0.74), lower neighbourhood deprivation scores (0.72 (0.59-0.93), 0.78 (0.58- 1.04), 0.62 (0.39-1.00)), higher quintiles of physical activity (3.18 (2.29-4.41), 4.25 (2.91-6.20), 8.33 (5.58-12.44), 6.58 (4.07-10.64)), highest quintile of screen time (1.83 (1.31-2.56), greater availability of sports outside school (1.68 (1.22- 2.32)), better sport management (2.57 (1.63-4.07)) and provision of sport courts at school (0.57 (0.40-0.81)). Conversely, obesity was associated with less time spent participating in sport (0.50 (0.31-0.80)). Conclusion: Results support the use of sport participation as an effective strategy to increase physical activity levels and identify target groups and areas for interventions, program design and policy development. Interventions should focus on improving accessibility to sport programs for all adolescents, providing adequate sport grounds at school, and promoting good sport management practices. Programs and policies encouraging sport participation should address in particular the needs of adolescents living in deprived neighborhoods, those attending coeducational and girls-only schools, and those who are obese. [ABSTRACT FROM AUTHOR]

The prevalence of overweight and obesity is increasing worldwide at an alarming rate. An Internet-based weight-loss programme has the potential to reach larger numbers of people than traditional face-to-face programmes. A growing body of evidence supports the use of low glycaemic load (GL) diets for weight loss. The present study aimed to investigate the efficacy of an Internet-based weight-loss programme that included foods with a low GL. One hundred and three volunteers, with a body mass index (BMI) ≥28 kg m, enrolled into an Internet weight-loss programme. A dietitian counselled participants over the Internet via weekly interactive chat rooms and monthly e-mails. Participants self-recorded body weight and food intake directly on to the Internet site. Weight, BMI and waist circumference were measured, and dietary data collected, at baseline and 6 months. Seventy participants completed the 6-month weight-loss programme. Among these, mean weight, BMI and waist circumference significantly decreased by 3.5 kg (95% CI = 2.3-4.7), 1.2 kg m (95% CI = 0.8-1.7) and 4.8 cm (95% CI = 2.8-6.8), of baseline values respectively ( P < 0.001). Twenty-five (36%) of the 70 participants lost a clinically significant amount of weight (>5% of initial body weight). This descriptive study has shown that an Internet-based weight-loss programme with low GL principles can promote weight loss. This type of intervention and approach could be used to enhance other weight-loss strategies. [ABSTRACT FROM AUTHOR]

Research measuring whole-body protein turnover (WBPT) after both exercise and nutrition has generally focused on resistance exercise; however, there is a paucity of data regarding the effect of postaerobic exercise nutrition, especially in older adults. It is not known if postexercise protein feeding has a beneficial effect on protein turnover after low- to moderate-intensity exercise. We investigated whether consuming protein plus carbohydrate (PRO) immediately after an acute bout of aerobic exercise has an additive effect over carbohydrate alone (CHO) on WBPT in older individuals. Twelve healthy older adults (age, 59 ± 4 years) were studied on 2 separate occasions after 1 h of exercise at approximately 50% of maximal rate of oxygen uptake, followed by 4 h of recovery. Immediately following exercise, subjects ingested a CHO (60 g) or an isocaloric PRO beverage (40 g carbohydrate, 20 g whey protein). Whole-body protein metabolism was determined using [1-13C]leucine infusion (60 mg prime; 75 mg·h-1 continuous), and sampling blood and expired breath. Rates of whole-body leucine appearance and oxidation, and nonoxidative leucine disposal during the third and fourth hours of postexercise recovery were higher in the PRO group (2.51 ± 0.55, 0.78 ± 0.37, and 1.71 ± 0.44 µmol·kg-1·min-1, respectively) than in the CHO group (1.81 ± 0.27, 0.33 ± 0.14, and 1.47 ± 0.25 µmol·kg-1·min-1, respectively; p = 0.001). Our results indicate that consumption of a PRO beverage after aerobic exercise increased WBPT to a greater extent than a CHO beverage. Les études s'intéressant à la mesure du renouvellement global des protéines dans l'organisme (WBPT) à la suite d'un exercice physique et d'un apport alimentaire traitent généralement du rôle des exercices de force; néanmoins, il y a peu d'études sur les effets d'un apport alimentaire à la suite d'un exercice aérobie particulièrement chez les personnes âgées. On ne sait pas si un apport protéique après un exercice suscite un effet bénéfique sur le renouvellement protéique consécutif à un exercice d'intensité légère à modérée. Cette étude se propose de vérifier si, comparativement à un apport de sucres seulement (CHO), un apport protéique combiné à des sucres (PRO) immédiatement après un bref effort aérobie apporte des effets additionnels concernant le WBPT chez des personnes âgées. On invite en deux occasions douze adultes en bonne santé et âgés de 59 ± 4 ans à participer à une séance d'exercice d'une durée de 60 min et d'intensité suscitant 50 % du consommation d'oxygene maximale suivie d'une récupération d'une durée de 4 h. Immédiatement après la fin de l'exercice, les sujets consomment soit une boisson contenant des sucres (CHO; 60 g) soit une boisson contenant des sucres et des protéines (PRO; 40 g de sucres et 20 g de protéines lactosériques) totalisant la même quantité d'énergie. On évalue le métabolisme protéique de l'organisme en entier par l'administration de [1-13C] leucine (infusion immédiate de 60 mg suivie d'une perfusion à raison de 75 mg·h-1) et l'analyse des échantillons de sang et des gaz expirés. Les taux corporels d'apparition de la leucine, de son oxydation et de l'élimination de la fraction non oxydée au cours de la 3e et de la 4e heure de la période de récupération postexercice sont plus importants dans la condition PRO (2,51 ± 0,55, 0,78 ± 0,37 et 1,71 ± 0,44 μmol·kg-1·min-1 respectivement) que dans la condition CHO (1,81 ± 0,27, 0,33 ± 0,14 et 1,47 ± 0,25 μmol·kg-1·min-1 respectivement) (p = 0,001). Nos observations révèlent qu'un apport de protéines à la suite d'un exercice aérobie suscite une plus grande augmentation du WBPT que ne le fait un apport de sucres. Un apport protéique à la suite d'un exercice semble favorable à l'amélioration de la qualité des protéines contenues dans l'organisme en entier et pourrait apporter des gains en matière de capacité physique chez les personnes âgées. [ABSTRACT FROM AUTHOR]