Measures of Fluid Loss during Surfing: A Preliminary Analysis in Recreational Surfers

Surfing is a popular sport, but little is known about the extent to which recreational surfers experience fluid loss from this activity. The principal objective of this research was to estimate fluid loss during a surfing session through changes in pre- to post-session urine color (Ucol), urine osmolality (Uosm), and body mass (BM). Data were collected from 11 recreational surfers across 14 surf sessions conducted under various environmental (mean water temperature = 22.1 SD ± 2.3; range = 20-26oC; air temperature range = 13.1-31.5oC; relative humidity range = 37.5-88.1%) and surfing conditions (e.g. winter/summer, wave type, location, environmental and water conditions). Linear mixed effects models indicated that participants experienced significant pre- to post-session changes in BM (p \u3c 0.001), but not in Ucol or Uosm. These findings suggested that recreational surfers may experience fluid loss (measured by pre- to post-surfing BM) that may impact on their performance and health, and therefore they should adopt a hydration strategy to minimize this impact

Six year follow-up of students who participated in a school-based physical activity intervention: a longitudinal cohort study

Background: The purpose of this paper was to evaluate the long-term impact of a childhood motor skill intervention on adolescent motor skills and physical activity. Methods: In 2006, we undertook a follow-up of motor skill proficiency (catch, kick, throw, vertical jump, side gallop) and physical activity in adolescents who had participated in a one year primary school intervention Move It Groove It (MIGI) in 2000. Logistic regression models were analysed for each skill to determine whether the probability of children in the intervention group achieving mastery or near mastery was either maintained or had increased in subsequent years, relative to controls. In these models the main predictor variable was intervention status, with adjustment for gender, grade, and skill level in 2000. A general linear model, controlling for gender and grade, examined whether former intervention students spent more time in moderate-to-vigorous physical activity at follow-up than control students. Results: Half (52%, n = 481) of the 928 MIGI participants were located in 28 schools, with 276 (57%) assessed. 52% were female, 58% in Grade 10, 40% in Grade 11 and 54% were former intervention students. At follow-up, intervention students had improved their catch ability relative to controls and were five times more likely to be able to catch: OR catch = 5.51, CI (1.95 - 15.55), but had lost their advantage in the throw and kick: OR throw = .43, CI (.23 - .82), OR kick = .39, CI (.20 - .78). For the other skills, intervention students appeared to maintain their advantage: OR jump = 1.14, CI (.56 - 2.34), OR gallop = 1.24, CI (.55 - 2.79). Intervention students were no more active at follow-up. Conclusion: Six years after the 12-month MIGI intervention, whilst intervention students had increased their advantage relative to controls in one skill, and appeared to maintain their advantage in two, they lost their advantage in two skills and were no more active than controls at follow up. More longitudinal research is needed to explore whether gains in motor skill proficiency in children can be sustained and to determine the intervention characteristics that translate to subsequent physical activity

Three year follow-up of an early childhood intervention : is movement skill sustained?

BackgroundMovement skill competence (e.g. the ability to throw, run and kick) is a potentially important physical activity determinant. However, little is known about the long-term impact of interventions to improve movement skills in early childhood. This study aimed to determine whether intervention preschool children were still more skill proficient than controls three years after a 10 month movement skill focused intervention: &lsquo;Tooty Fruity Vegie in Preschools&rsquo;.MethodsChildren from 18 intervention and 13 control preschools in NSW, Australia were assessed at ages four (Time1), five (T2) and eight years (T3) for locomotor (run, gallop, hop, leap, horizontal jump, slide) and object control proficiency (strike, bounce, catch, kick, overhand throw, underhand roll) using the Test of Gross Motor Development-2. Multi-level object control and locomotor regression models were fitted with variables time, intervention (yes/no) and a time*intervention interaction. Both models added sex of child and retained if significant, in which case interactions of sex of child with other variables were modelled and retained. SPSS (Version 17.0) was used.ResultsOverall follow-up rate was 29% (163/560). Of the 137 students used in the regression models, 53% were female (n = 73). Intervention girls maintained their object control skill advantage in comparison to controls at T3 (p = .002), but intervention boys did not (p = .591). At T3, there were no longer intervention/control differences in locomotor skill (p = .801).ConclusionEarly childhood settings should implement movement skill interventions and more intensively target girls and object control skills.<br /

Phenotypic leaf variation in Avicennia marina in tropical Australia: can discrete subpopulations be recognised in the field?

The geographic patterns of phenotypic variation in leaf morphology traits were studied in the mangrove Avicennia marina (Forsk.) Vierh. in tropical Queensland, Australia, to determine whether discrete subpopulations could be recognised in the field. Significant differences in the various leaf characters occurred among the sites, which were not explained by longitude or latitude, nor by inter-site distances. Hierarchical cluster analysis of the estimated site means showed no coherent geographical groupings of the sites, suggesting that site populations do not follow a differentiation by distance model. Principal component analysis showed that site groupings with consistent leaf morphological characteristics could be identified, suggesting the A. marina occurs as widely scattered discrete subpopulations, and that phenotypic structuring occurs over quite short (km) distances. Evidence from other studies suggests this phenotypic structuring reflects underlying genetic diversity, and it implies that a conservative approach to sourcing plant material for mangrove restoration projects would be appropriate

Reduced salinity decreases the fertilization success and larval survival of two scleractinian coral species

Successful reproduction by scleractinian corals is essential for the maintenance of populations that form the foundation of coral reef ecosystems. Laboratory experiments were done to determine the effects of reduced salinity on the fertilization success and larval survival of two coral species, Platygyra daedalea and Acropora millepora, from the Great Barrier Reef, Australia. Fertilization rates of P. daedalea and A. millepora were significantly reduced at 25.8 psu and 33.1 psu, respectively, and completed blocked at 18.4 psu for A. millepora. The estimated larval survival times were similar from 36.8 to 25.8 psu (P. daedalea 291–312 h, A. millepora 207–264 h), whereas the 18.4 psu treatment resulted in estimates of 153 h and 24 h for P. daedalea and A. millepora, respectively. These results demonstrate that reduced salinity is detrimental to the reproductive success of these corals, and if salinity is lowered by natural or anthropogenic sources during spawning, this would lead to decreased reproductive success and recruitment on reefs

Effects of garlic oil on platelet aggregation: a double blind placebo controlled crossover study

The use of antiplatelet therapies decreases the incidence of mortality in persons prone to cardiovascular events. Several in vitro studies suggest that garlic may decrease platelet aggregation. We aimed to test the acute effects of garlic on platelet aggregation in 14 healthy volunteers using a randomised, double-blind, placebo-controlled, crossover research method. The active agent tested was solvent-extracted garlic oil incubated in ethanol to obtain organosulphur compounds that demonstrate the highest antiplatelet activity when tested in vitro. Platelet aggregation was induced ex vivo by adrenaline, collagen or adenosine diphosphate (ADP). Four hours after consuming one large dose of oil derived from 9.9 g garlic, there was little or no effect in the reduction of platelet aggregation. Platelet aggregation induced by adrenaline was reduced slightly but significantly (P \u3c 0.05; 12% reduction). The oil had no effect on collagen- or ADP-induced aggregation. The results of this controlled trial indicate that this type of garlic oil should not be relied on in persons with conditions in which reductions in platelet aggregation are desired or necessary

What do changes in prematch vs. postmatch, 1, 2, and 3 days postmatch body weight tell us about fluid status in English premiership rugby union players?

This study investigated changes in body weight pre and postmatch and 1, 2, and 3 days postmatch. Thirty-six players contracted to an English Premiership rugby union club had their pre and postmatch body weight and 1, 2, and 3 day postmatch body weight recorded across 14 matches played (10 at home and 4 away) during the official 2003-2004 professional rugby union season, representing a total of 262 player appearances. Body weight was recorded using a set of calibrated Seca digital scales with players wearing underwear only and toweled dry of all sweat (postmatch). Players were allowed to ingest fluid ad libitum throughout each match. A number of players recorded pre to postmatch reductions of body weight of \u3e2% with some as high as 4.9%. Significant position-specific mean reductions in prematch to postmatch body weight (�SD) were found for both forwards (1.94 � 0.14 kg) and backs (1.04 � 0.17 kg). The mean gain in postmatch to 1-day postmatch body weight was significant for forwards (1.40 � 0.27 kg) but not for backs (0.76 � 0.30 kg). There were no significant mean differences between prematch and 2 or 3 days postmatch body weight for either forwards or backs. Forwards on average lost a significantly greater proportion of their weight pre to postmatch than backs (p = 0.005). Forwards were on average 99.5% of the prematch weight at 1 day postmatch, whereas backs were 99.7% (p = 0.598). Forwards were 99.6% of their prematch weight at 3 days postmatch, whereas backs were 100.4% (p = 0.035). Changes in fluid status can be effectively monitored by recording changes in body weight and is useful where players are undertaking training sessions within 1, 2, or 3 days after their last match as a measure of rehydration status