Kerli Mooses

Running economy and body composition between competitive and recreational level distance runners

The aim of the present study was to compare running economy between competitive and recreational level athletes at their individual ventilatory thresholds on track and to compare body composition parameters that are related to the individual running economy measured on track. We performed a cross-sectional analysis of a total 45 male runners classified as competitive runners (CR; n = 28) and recreational runners (RR; n = 17). All runners performed an incremental test on treadmill until voluntary exhaustion and at least 48 h later a 2 × 2000 m test at indoor track with intensities according to ventilatory threshold 1, ventilator threshold 2. During the running tests, athletes wore portable oxygen analyzer. Body composition was measured with Dual energy X-ray absorptiometry (DXA) method. Running economy at the first ventilatory threshold was not significantly related to any of the measured body composition values or leg mass ratios either in the competitive or in the recreational runners group. This study showed that there was no difference in the running economy between distance runners with different performance level when running on track, while there was a difference in the second ventilatory threshold speed in different groups of distance runners. Differences in running economy between competitive and recreational athletes cannot be explained by body composition and/or different leg mass ratios.

Different Methods Yielded Two-Fold Difference in Compliance with Physical Activity Guidelines on School Days.

Introduction The aim was to compare the average and the days method in exploring the compliance of children with physical activity guidelines and describe their physical activity patterns in different school day segments. Methods Physical activity was objectively measured in 472 children aged 6–13 for one school week. Children were compliant when fulfilling PA recommendations 1) on average over all measured days (average method) or 2) on at least four measured days (days method). To explore the difference in moderate to vigorous physical activity (MVPA) minutes between compliant and non-complaint children (using both the average and days method) in various day segments, linear mixed models was used. Results Compliance with physical activity guidelines was significantly higher with the average compared to the days method (51.7% and 23.7%, respectively). In segmented-day analysis, compliant children accrued more MVPA minutes in all day segments, especially during after-school. Gender differences appeared only during the in-school segments, where girls spent less time in MVPA (average method: -4.39 min, 95% CI = -5.36,-3.42, days method: -4.45 min, 95%CI = -5.46,-3.44). Older children accrued more MVPA minutes during physical education classes, but less during breaks, compared to younger children. Conclusions The used methods yielded remarkably different prevalence estimates for compliance to physical activity recommendations. To ensure comparability between studies, interventions and reports, there is a need for internationally agreed operationalization and assessment methods of physical activity guidelines. As non-compliant children had lower MVPA during all day segments, greater efforts should be made to provide physical activity opportunities both during and after school.

Physical Education Increases Daily Moderate to Vigorous Physical Activity and Reduces Sedentary Time

BACKGROUND Physical activity (PA) is important to mental and physical health. Physical education (PE) lessons have the potential to increase daily moderate to vigorous PA (MVPA) and reduce sedentary time (SED). We measured MVPA and SED in primary school PE, determined the contribution of PE to daily MVPA and SED, and compared PA on days with and without PE. METHODS PA was measured in 504 first (ages 7-9) and second (ages 10-12) school level children for 1 school week, with inclusion criteria of at least 10 hours of valid data. Linear mixed methods were used for data analysis. RESULTS In PE, students spent 28.6 ± 16.5% in MVPA and 29.3 ± 19.8% in SED. Each additional MVPA minute in PE was associated with 1.4 more daily MVPA minutes. On days with PE, students had 12.8 (95% CI 10.5; 15.0) minutes more MVPA and 9.7 (95% CI 16.3; 3.1) minutes less SED compared with days without PE. CONCLUSIONS Although MVPA in PE was relatively low and SED high, PE significantly increased daily MVPA and reduced SED, confirming the important role of PE in supporting the healthy development of children.