Determination of peak cardiorespiratory fitness parameters in children: which averaging method should we use?

The purpose of this study was to identify which averaging methods most accurately measures peak cardiorespiratory fitness (CRF) parameters [peak O₂ uptake (VO₂), peak O₂pulse and peak respiratory exchange ratio (RER)] in a sample of healthy children and adolescents. In this cross-sectional multicenter study, we recruited 278 healthy children aged 12–17 years. We compared the mean peak value of three CRF parameters using the recommended averaging methods (30-second block average) with alternative averaging methods such as moving averages or shorter smoothing periods. We also assessed averaging methods for accuracy by individually reviewing breath-by-breath scatter plots. The 30-second block average method resulted in a lower mean peak VO₂ and in an increased proportion of underestimated peak values. Using a 30-second moving average significantly increased mean peak values which increased accuracy. Similar results were found for peak RER and peak O₂pulse. In conclusion, the currently recommended averaging method (30-second block average) increased the risk of misinterpretation of peak CRF values in children. Using a moving average approach decreased misinterpretation and increased accuracy.     

Can physical activity eliminate the mortality risk associated with poor sleep?A 15-year follow-up of 341,248 MJ Cohort participants

Background:This study examined the joint associations of sleep patterns and physical activity(PA) with all-cause,cardiovascular disease(CVD),and cancer mortality.Methods:A total of 341,248 adults(mean age=39.7 years;men:48.3%) were included in the study,with a 15-year follow-up.Participants reported sleep duration and disturbances(difficulty falling asleep,easily awakened,or use of sleeping medication).PA was classified into 4 levels:<7.5,7.5-14.9,15.0-29.9,and>30.0 metabolic equivalent ho...     

Defensive transition in soccer – are prompt possession regains a measure of success? A quantitative analysis of German Fußball-Bundesliga 2010/2011

Abstract

The aim of the study was to evaluate the time required by German Bundesliga soccer teams to recover ball possession – which was operationalised as defensive reaction time – and identify both the differences between top teams and the rest of the league and the influence of match status on the aforementioned indicator. Therefore, teams were classified into 3 distinct groups according to their final league position: top, in-between and bottom. In total, all 306 games of the season 2010/2011 were analysed post-event. Top teams recovered ball possession quickest after losing it in comparison to the other groups and demonstrated lower defensive reaction times (approximately 1 s in each match status) compared to the remaining teams. Moreover, all groups showed the lowest defensive reaction times when trailing. The results of this study imply that recovering ball possession as quickly as possible after losing possession was an important determinant of successful defensive performance in German Bundesliga season 2010/2011. Further, the current score seemed to be highly influential on the defensive reaction time. The implications of the results for future research, especially considering opponent interactions, are critically discussed.     

Weekday–weekend variations in mother-/father–child physical activity and screen time relationship: A cross-sectional study in a random sample of Czech families with 5- to 12-year-old children

This study assessed the associations between these factors in a random sample of Czech families with preschool and school-aged children. A nationally representative sample comprised 185 families with preschool children and 649 families with school-aged children (dyads; both parents and child n?=?365, mother and child n?=?730, and father and child n?=?469). The participants wore Yamax Digiwalker SW-200 pedometers at least four weekdays and both weekend days and completed family logbooks (anthropometric parameters, daily step counts (SC), and screen time (ST)). When a parent (fathers at weekends and mothers both on weekdays and at weekends) achieved 10,000 SC per day, their children were also significantly (OR?=?2.93–6.06, 95% CI?=?2.02–9.26) more likely to meet the daily SC recommendation. On the contrary, the involvement of fathers in organized leisure-time PA reduced their children's odds of meeting the SC recommendation on weekdays (OR?=?0.53, 95% CI?=?0.31–0.89) and at weekends (OR?=?0.41, 95% CI?=?0.24–0.72). The excessive ST of parents at weekends reduced the odds of their children meeting the SC recommendation (mother–child dyads: OR?=?0.44, 95% CI?=?0.26–0.72; father–child dyads: OR?=?0.63, 95% CI?=?0.37–1.06). High levels of parents’ PA contribute to the achievement of the recommended daily PA in children on weekdays and at weekends. Excessive weekend ST of parents reduces their odds of their children achieving the recommended daily PA; however, the influence of parents’ PA on their children’s achieving the recommended daily PA is stronger than the inhibitory effect of ST.