Background: This study examined the distribution of objectively measured physical activity (PA) and sedentary time of fifth-grade students during school, leisure time, and physical education (PE) classes. Demographic, anthropometric, and PA data were collected from 17 representative Finnish schools. Methods: To estimate the PA and sedentary time, participants (N = 592) wore wGT3X-BT ActiGraphs for 7 consecutive days. Comparisons were made between genders and different BMI groups. Results: From the study sample, 43.7% met the moderate to vigorous PA (MVPA) guidelines. Participants spent 62.2% of the day sedentary and 8.2% in moderate and vigorous activities. Boys performed more MVPA than girls, and girls were more sedentary during school days. Boys had more MVPA than girls in leisure time, but there were no differences in sedentary time. However, an examination of PA assessed during PE classes revealed no differences between boys and girls. Normal-weight boys engaged in more MVPA than overweight and obese boys. No differences were found for girls. Conclusions: The PA levels differ between different BMI groups in leisure time and during school but not during PE lessons. PA for overweight children should be targeted and compulsory PE time should be increased to achieve the PA guidelines.
Kasper Salin, Mikko Huhtiniemi, Anthony Watt, Harto Hakonen and Timo Jaakkola
Sami Yli-Piipari, Janne Santeri Kulmala, Timo Jaakkola, Harto Hakonen, Joseph Cole Fish and Tuija Tammelin
Schools are in a unique position to ensure that all students meet the current physical activity (PA) recommendations. This study aimed to examine 1st to 3rd grade elementary students’ accelerometer measured school day PA in the United States (U.S.) and Finland.
The sample consisted of 200 students (107 girls, 93 boys; ages 6 to 8) and their school day PA was monitored with hip-worn ActiGraph GT3X+ accelerometers across a 5-day school week and the thresholds 100 and 2296 count per minute were used to separate sedentary time, light PA, and moderate-to-vigorous PA (MVPA).
On an average school day, students were engaged in MVPA for 20.0 min in the U.S. and 24.1 min in Finland. Students’ school-day MVPA was 9 to 16 minutes higher during physical education (PE) days compared with non-PE days (U.S: 25.8 vs. 16.6 min/day; Finland: 36.3 vs. 20.1 min/day). Girls had less MVPA and more sedentary time compared with boys in both samples.
This study highlights both the role of PE and other school day physical activities in meeting PA guidelines. Policy measures are needed to change the structure of the school day and enhance PA to ensure that students meet the PA recommendations.
Heidi J. Syväoja, Anna Kankaanpää, Jouni Kallio, Harto Hakonen, Janne Kulmala, Charles H. Hillman, Anu-Katriina Pesonen and Tuija H. Tammelin
Background: This study investigated the associations of subjectively and objectively measured physical activity (PA) and sedentary behavior with academic achievement. We further examined whether aerobic fitness, obesity, and bedtime mediate these associations. Methods: This study included 970 children aged 9–15 years (52.3% girls) from 9 schools throughout Finland. Register-based academic achievement [grade point average (GPA)] as well as self-reported and accelerometer-measured PA/sedentary behavior were assessed during spring 2013. Aerobic fitness (assessed via a maximal shuttle run test), body composition (assessed via bioimpedance analysis), and self-reported bedtime were collected. Structural equation modeling was applied to examine the associations. Standardized regression coefficients are presented. Results: Self-reported PA had a direct positive [β = 0.084; 95% confidence interval (CI), 0.023 to 0.145] and an indirect positive association with GPA through higher aerobic fitness (β = 0.061; 95% CI, 0.033 to −0.087). Accelerometer-based PA was not associated with GPA. Self-reported screen time had an indirect negative association with GPA through later bedtime (β = −0.071; 95% CI, −0.096 to −0.035) and lower aerobic fitness (β = −0.039; 95% CI, −0.059 to 0.019). Nonscreen sedentary time had a direct positive (β = 0.193; 95% CI, 0.101 to −0.289) and an indirect negative association with GPA through lower aerobic fitness (β = −0.040; 95% CI, −0.063 to −0.016). Conclusions: Participating in PA, avoiding excessive screen time, and going to bed earlier may benefit academic achievement.
Matti Hyvärinen, Sarianna Sipilä, Janne Kulmala, Harto Hakonen, Tuija H. Tammelin, Urho M. Kujala, Vuokko Kovanen and Eija K. Laakkonen
Purpose: To investigate the validity and test–retest reliability of a single seven-level scale physical activity assessment question (SR-PA L7) and its three-level categorization (SR-PA C3). Methods: The associations of SR-PA L7 and C3 with accelerometer-measured leisure-time physical activity (ACC-LTPA) and with the results of four different physical performance tests (6-min walk [n = 733], knee extension [n = 695], vertical jump [n = 731], and grip force [n = 780]) were investigated among women aged 47–55 years participating in the Estrogenic Regulation of Muscle Apoptosis study (n = 795). The reliability was studied using Spearman correlations with 4-month test–retest period (n = 152). Results: SR-PA L7 and C3 had low correlations with ACC-LTPA (r s = .105–.337). SR-PA L7, SR-PA C3, and ACC-LTPA explained comparable but small amount of variance of the physical performance test results. The reliability analysis provided moderate agreement (r s = .707 and .622 for SR-PA L7 and C3, respectively). Conclusions: SR-PA L7 and C3 demonstrated limited validity and reasonable repeatability.