The evolution of Web‐based peer‐review systems

Web‐based peer‐review systems are ubiquitous within scholarly publishing today, providing valuable efficiencies for authors, editors, and referees. These systems are the result of a general evolution from paper‐based workflows to electronic processes that began in the 1970s. DOS‐based systems paved the way for Windows desktop systems and, in the mid‐1990s, Web‐based peer review. Governmental, academic, and commercial stakeholders all participated in advancing the state of peer review by experimenting with different technologies, workflows, and features. These experiments have coalesced into a new steady state in which Web‐based peer‐review systems are the norm, and in which continued evolution tends to focus on incremental improvements to traditional workflow.     

Physiological responses and time-motion characteristics of various small-sided soccer games in youth players

The aim of this study was to examine acute physiological responses and time-motion characteristics associated with three different small-sided soccer game formats in youth players. Sixteen male soccer players aged 16.3+/-0.6 years (mean+/-s) completed three variations of a small-sided game (i.e. 2 vs. 2, 4 vs. 4, and 6 vs. 6 players) in which heart rate, rating of perceived exertion (RPE), blood lactate concentration, and time-motion characteristics were recorded. The pitch size was altered to keep the relative pitch area per player consistent for each game format. The 2 vs. 2 games exhibited greater blood lactate, heart rate, and RPE responses compared with 4 vs. 4 and 6 vs. 6 games (P<0.05). The players travelled less (P<0.05) distance at speeds of 0-7 km.h(-1) in the 4 vs. 4 compared with the 2 vs. 2 games (1128+/-10 m and 1176+/-8 m, respectively). Average maximal sprint distances above 18 km.h(-1) were lower (P<0.05) in 2 vs. 2 than in 4 vs. 4 and 6 vs. 6 games (11.5+/-3.9 m, 15.3+/-5.5 m, and 19.4+/-5.9 m, respectively), and in 4 vs. 4 compared with 6 vs. 6 games. The results show that as small-sided game formats decrease in size and relative pitch area remains constant, overall physiological and perceptual workload increases.     

Intensity and physiological strain of competitive ultra-endurance exercise in humans

The aim of this study was to determine the magnitude and pattern of intensity, and physiological strain, of competitive exercise performed across several days, as in adventure racing. Data were obtained from three teams of four athletes (7 males, 5 females; mean age 36 years, s = 11; cycling .VO(2 peak) 53.9 ml . kg(-1) . min(-1), s = 6.3) in an international race (2003 Southern Traverse; 96 - 116 h). Heart rates (HR) averaged 64% (95% confidence interval: +/- 4%) of heart rate range [%HRR = (HR - HR(min))/(HR(max) - HR(min)) x 100] during the first 12 h of racing, fell to 41% (+/-4%) by 24 h, and remained so thereafter. The level and pattern of heart rate were similar across teams, despite one leading and one trailing all other teams. Core temperature remained between 36.0 and 39.2 degrees C despite widely varying thermal stress. Venous samples, obtained before, during, and after the race, revealed increased neutrophil, monocyte and lymphocyte concentrations (P < 0.01), and increased plasma volume (25 +/- 10%; P < 0.01) with a stable sodium concentration. Standardized exercise tests, performed pre and post race, showed little change in the heart rate-work rate relationship (P = 0.53), but a higher perception of effort post race (P < 0.01). These results provide the first comprehensive report of physiological strain associated with adventure racing.     

Effects of time of day and distance upon accuracy and consistency of throwing darts

We examined variations in dart-throwing performance during the daytime in 12 participants. Two distances from the dartboard were investigated - the normal distance (short throws) and another 50% further away than this (long throws). Intra-aural temperature and subjective fatigue were measured, and errors in performance were assessed as the radial distances of throws from the bulls-eye and the standard deviation of these distances. Long-distance throws improved significantly throughout the daytime and correlated positively with intra-aural temperature (r= -0.49, P=0.002 and r= -0.49, P=0.002 for errors and standard deviation of errors, respectively), but not with subjective fatigue (r= -0.10, P=0.56 and r= -0.05, P=0.74 for errors and standard deviation of errors, respectively). Short-distance throws were associated less with intra-aural temperature (r= -0.46, P= 0.005 and r= -0.17, P=0.31 for errors and standard deviation of errors, respectively), and worsened with fatigue (r=+0.34, P= 0.040 for errors). Compared with the short-distance throws, the long-distance throws were performed significantly less well than could be accounted for by the increased distance (mean errors were increased 1.67-2.78 times and standard deviation of errors of errors 1.58-3.68 times), supporting the concept of a trade-off between force of contraction and accuracy of performance. Throwing darts can be used as a model for investigating factors that influence motor performance, and our results indicate that the effects of time of day upon performance depend upon the relative importance of force and accuracy.     

Prediction of fat and fat-free mass in male athletes using dual X-ray absorptiometry as the reference method

The ability of bioelectrical impedance analysis and anthropometry to predict fat mass and fat-free mass was compared in a sample of 82 male athletes from a wide variety of sports, using dual-energy X-ray absorptiometry (DXA) as the reference method. The percent fat measured by DXA was 10.9+/-4.9% (mean +/- s), and fat mass was predicted with a standard error of the estimate of 1.7 kg for skinfolds and 2.8 kg for bioelectrical impedance analysis (P < 0.001). Fat-free mass was predicted with a standard error of the estimate of 1.7 kg for anthropometry and 2.6 kg for bioelectrical impedance analysis (P < 0.001). Regression of various individual skinfolds and summed skinfolds, to examine the effect of skinfold selection combinations by stepwise regression, produced an optimal fat mass prediction using the thigh and abdominal skinfold sites, and an optimal fat-free mass prediction using the thigh, abdominal and supra-ilium sites. These results suggest that anthropometry offers a better way of assessing body composition in athletes than bioelectrical impedance analysis. Applying the derived equations to a separate sample of 24 athletes predicted fat and fat-free mass with a total error of 2.3 kg (2.9%) and 2.2 kg (2.7%), respectively. Combining the samples introduced more heterogeneity into the sample (n = 106), and the optimal prediction of fat mass used six skinfolds in producing a similar standard error of the estimate (1.7 kg), although this explained a further 4% of the variation in DXA-derived fat. Fat-free mass was predicted best from four skinfolds, although the standard error of the estimate and coefficient of determination were unchanged.