Seasonal variations in physical fitness among elementary school children

Association between time of assessment within a school year and physical fitness of primary school children

The dissociation of effects of age, time of assessment and cohort is a well-known challenge in developmental science. We examined effects of time of assessment in the school year on children's physical fitness using data from 75,362 German third-graders from seven cohorts. Children were tested once either in the first or second school term of third grade. Tests examined cardiorespiratory endurance (6-min run), coordination (star-run), speed (20-m sprint), lower (standing long jump) and upper (ball-push test) limbs muscle power, and flexibility (stand-and-reach test). We estimated the effect of time of assessment using a regression discontinuity design specified in a linear mixed model with random factors child and school and adjusted for age, sex, and cohort effects. Coordination, speed, and upper limbs muscle power were better in second compared to first school term, with boys exhibiting a larger increase of upper limbs muscle power than girls. There was no evidence for changes in cardiorespiratory endurance, lower limbs muscle power, and flexibility between assessments. Previously reported age and sex effects as well as secular fitness trends were replicated. There is thus evidence for improvement of some physical fitness components beyond age and cohort effects that presumably reflects the benefit of physical activity in physical education and other settings. Effects of assessment time should be taken into consideration in performance-based grading or norm-based selection of children.

Changes in Physical Fitness during Summer Months and the School Year in Austrian Elementary School Children-A 4-Year Longitudinal Study

Even though physical fitness is an important component in children's health and well-being, there has been a decline in physical fitness over the last several decades. The present study examined potential differences in the development of physical fitness during the academic year and summer vacation in Austrian elementary-school children. A total of 214 children (52.3% boys) completed the German motor test in the fall (after summer vacation) and spring (prior to summer vacation) of every grade throughout their elementary school years. This resulted in eight assessments of cardio-respiratory endurance, muscular fitness, flexibility, speed, agility, and balance over a 4-year period. As expected, physical fitness increased with age but the improvement in cardio-respiratory endurance and muscular fitness was more pronounced during summer vacation (p < 0.01), while the improvement in speed was more pronounced during the academic year (p < 0.01). These results indicate an influence of weather conditions on health-enhancing physical activity in addition to structural and social support. Particularly in geographical regions with cold winters and shorter days, health-enhancing physical activity may be limited. Accordingly, schools need to provide additional opportunities to ensure an adequate amount of physical activity that stimulates the development of physical fitness.

Factors associated with motor performance among overweight and nonoverweight Tyrolean primary school children

BACKGROUND

The increasing prevalence of overweight and obesity among children is often associated with motor deficits. Motor performance among children partly depends on modifiable factors, for example, weight status, electronic media use, sports club participation, and on nonmodifiable factors, for example, sex, age, migration background, or socio-economic status.

AIM

To evaluate factors associated with motor performance among overweight and nonoverweight Tyrolean primary school children.

METHODS

Height, weight, and sport motor performance of primary school children were measured using the German motor performance test DMT 6-18. In addition, children were asked about migration background, sports club participation, and electronic media use in their room.

RESULTS

A total of 304 children (48.7% girls) with a mean age of 8.0 ± 1.2 years were tested. In total, 61 (20.1%) children were overweight or obese. Regarding motor performance, nonoverweight children showed significantly higher total z-scores (106.8 ± 5.7 vs. 102.4 ± 6.8). For the total cohort, results of the multiple linear regression analysis (R (2) = 0.20) revealed that factors male sex (β = 0.12), nonoverweight children (β = 0.28), higher school grade (β = 0.23), sports club participation (β = 0.18),and > 2 weekly lessons of physical education (β = 0.26) were associated with an increased motor performance. For nonoverweight children results of the multiple linear regression analysis (R (2) = 0.09) found that a higher school grade (β = 0.17), sports club participation (β = 0.16),and more than 2 weekly lessons of physical education (β = 0.22) were associated with an increased motor performance. For the overweight children, results of the multiple linear regression analysis (R (2) = 0 .43) showed that no migration background (β = 0.23), a higher school grade (β = 0.55), sports club participation (β = 0.33) and more than 2 weekly lessons of physical education (β = 0.48) were associated with an increased motor performance.

CONCLUSION

Regarding modifiable factors, motor performance among overweight and nonoverweight children is strongly associated with a higher number of weekly lessons in physical education. Therefore, daily lessons in physical education are strongly recommended to improve motor performance especially among overweight primary school children.

Family-Based Cluster Randomized Controlled Trial Enhancing Physical Activity and Motor Competence in 4-7-Year-Old Children

Little is known of how to involve families in physical activity (PA) interventions for children. In this cluster randomized controlled trial, we recruited families with four- to seven-year-old children to participate in a year-long study where parents in the intervention group families (n = 46) received tailored counseling to increase children’s PA. Structured PA was not served. Control group families (n = 45) did not receive any counseling. PA in all children (n = 91; mean age 6.16 ± 1.13 years at the baseline) was measured by accelerometers at the baseline and after three, six, nine and 12 months. Motor competence (MC) (n = 89) was measured at the baseline and after six and 12 months by a KTK (KörperkoordinationsTest für Kinder) and throwing and catching a ball (TCB) protocols. The effect of parental counseling on study outcomes was analyzed by a linear mixed-effects model fit by REML and by a Mann-Whitney U test in the case of the TCB. As season was hypothesized to affect counseling effect, an interaction of season on the study outcomes was examined. The results show significant decrease of MVPA in the intervention group when compared to the control group (p < .05). The TCB showed a nearly significant improvement at six months in the intervention group compared to the controls (p = .051), but not at 12 months. The intervention group had a steadier development of the KTK when the interaction of season was taken into account. In conclusion, more knowledge of family constructs associating with the effectiveness of counseling is needed for understanding how to enhance PA in children by parents. However, a hypothesis may be put forward that family-based counseling during an inactive season rather than an active season may provide a more lasting effect on the development of KTK in children.

TRIAL REGISTRATION

Controlled-Trials.com ISRCTN28668090.