The Role of Physical Education Homework to Adolescent Girls’ Physical Activity in Finland

This is a self-archived version of an original article. This version may differ from the original in pagination and typographic details. Author(s): Title: Year: Version: Copyright: Rights: Rights url: Please cite the original version: CC BY 4.0 https://creativecommons.org/licenses/by/4.0/ The Role of Physical Education Homework to Adolescent Girls’ Physical Activity in Finland © 2019 by authors and Scientific Research Publishing Inc Published version Kääpä, Mari; Palomäki, Sanna; Vähä-Ypyä, Henri; Vasankari, Tommi; Hirvensalo, Mirja Kääpä, M., Palomäki, S., Vähä-Ypyä, H., Vasankari, T., & Hirvensalo, M. (2019). The Role of Physical Education Homework to Adolescent Girls’ Physical Activity in Finland. Advances in Physical Education, 9(4), 223-239. https://doi.org/10.4236/ape.2019.94016 2019 Advances in Physical Education, 2019, 9, 223-239 https://www.scirp.org/journal/ape ISSN Online: 2164-0408 ISSN Print: 2164-0386 DOI: 10.4236/ape.2019.94016 Oct. 10, 2019 223 Advances in Physical Education The Role of Physical Education Homework to Adolescent Girls’ Physical Activity in Finland Mari Kääpä1*, Sanna Palomäki1, Henri Vähä-Ypyä2, Tommi Vasankari2, Mirja Hirvensalo1 1Faculty of Sport and Health Sciences, University of Jyväskylä, Jyväskylä, Finland 2UKK Institute Promoting Health-Enhancing Physical Activity, Tampere, Finland Abstract Introduction: There is an urgent need for active strategies to promote physical activity (PA) among female adolescents, as they are at greater risk of physical inactivity. In addition to Physical Education (PE) in school, to reach adequate levels of PA, young people need to participate in PA during the school day and/or after-school hours and/or in the beforeschool period. One week of objectively measured and selfreported information enlightens the status quo of adolescent girls’ PA and the role that PE homework plays. Purpose: The purpose of this study was to examine girls’ objectively measured PA in a lower secondary school as part of the Physical Education Homework Study, a project conducted in Finland. An additional aim was to provide insights into physical education (PE) homework as part of PA. Methods: Different levels of PA (i.e., light, moderate, vigorous), sedentary time, number of total steps and running steps were measured using accelerometers among girls in the 7th, 8th and 9th grades, aged between 12 and 15 years ( n = 88) for a period of 1 week. In addition, selfreported structured diaries were used to gather information abou t after school activities, including PE homework. An analysis of variance (ANOVA) and Tamhane’s post-hoc test was u sed to compare the different grades on the basis of participants’ PA levels and sedentary time. Data from self-reported PE homework frequenci es and time spent on PE homework were analysed using the independent-samples ttest. Results: The PE homework was a small aspect of the participants’ wholeday PA, averaging 34 minutes per week (7th grade girls 20 minutes, 8th grade girls 51 minutes, and 9th grade girls 32 minutes). Half of the girls from the 8th grade reached the 60-minute PA recommendation every day; 38% of all the girls met the recommended levels of PA. For the 7th grade girls, 35% met the recommendation, while 28% of the 9th grade girls reached the PA guidelines. The 7th grade girls recorded an average daily light PA time of 3 hours 28 minutes; this was 34 minutes more than the girls from 8th grade ( p = How to cite this paper: Kääpä, M., Palomäki , S., Vähä-Ypyä, H., Vasankari, T., & Hirvensalo, M. (2019). The Role of Physical Education Homework to Adolescent Girls ’ Physical Activity in Finland . Advances in Physical Educatio n, 9, 223-239. https://doi.org/10.4236/ape.2019.94016 Received: August 15, 2019 Accepted: October 7, 2019 Published: October 10, 2019 Copyright © 201 9 by author(s) and Scientific Research Publishing Inc. This work is licensed under the Creative Commons Attribution International License (CC BY 4.0). http://creativecommons.org/licenses/by/4.0/ Open Access M. Kääpä et al. DOI: 10.4236/ape.2019.94016 224 Advances in Physical Education 0.000) and 30 minutes more than the girls from the 9th grade ( p = 0.000). Conclusion: The PE homework provided a variety of PA for the adolescent girls’ after-school hours, even if the role of homework was not time-consuming (20 - 51 minutes per week). A possible way of prom oting active time among adolescents during after-school hours is to assign them PE homework, hence, active PE assignments could replace sedentary activities in adolescent girls’ lives. Keywords Physical Activity, Adolescent Girls, PE Homework, Accelerometer, Self-Report 1. Introduction In most countries, physical activity (PA) participation radically decreases during lower secondary school, especially among girls (Currie et al., 2008: pp. 105-107; Ekelund et al., 2012; Haapala et al., 2017). As a result, many adolescents fail to meet the recommended levels of PA (Currie et al., 2008; Pate & O’Neill, 2009; Husu, Vähä-Ypyä, & Vasankari, 2016). According to the Finnish National Physical Activity Recommendations, adolescents should be physically active more than 60 minutes per day (Tammelin & Karvinen, 2008). In Finland, only 10% - 17% of adolescents aged between 13 and 15 attain moderate-to-vigorous levels of PA, with the most radical decline in PA occurring among girls aged between 11 and 15, in their transition from childhood to adolescence (Kokko et al., 2015; Tammelin, Laine, & Turpeinen, 2013). According to Pate & O’Neill (2009), the objectively measured PA of adolescent girls declines at a rate of approximately 4% annually. This means that with time, the level of PA among girls recedes further from current PA guidelines. Nearly half of young people’s total daily PA accumulates after school, although the levels of after-school activity start to decrease gradually during preadolescence, while sedentary exposure increases as early as ages 9 to 11 (Wickel, Issartel, & Belton, 2013). Since female adolescents seem to be at greater risk of physical inactivity, there is an urgent need for effective strategies to promote PA among them (Aelterman et al., 2012). The after-school period represents a segment of the day in which adolescents’ health-enhancing levels of PA should be promoted (Beets et al., 2009). However, adolescents, particularly girls, accumulate low levels of moderate-to-vigorous physical activity (MVPA) during after-school hours, and their MVPA levels decline at a faster rate (Okely et al., 2011; Pate & O’Neill, 2009). According to Atkin et al. (2008), technology-based sedentary behaviour is the most prevalent activity among adolescents in after-school hours; the sedentary time of girls lasted for 35 minutes per day. Meanwhile, the times spent physically active amounted to 19 minutes for girls per day (Atkin et al., 2008). M. Kääpä et al. DOI: 10.4236/ape.2019.94016 225 Advances in Physical Education School is an important institution for PA promotion, as the vast majority of youths attend school. Thus, physical education (PE), as a structured school activity, has great potential in terms of public-health reach (Scruggs, 2007). There have been calls for schools to expand their efforts to increase PA-related opportunities to obtain higher levels of PA in adolescents, particularly adolescent girls. Even if school PE lessons are well organized and PA levels during these lessons are adequate, PE lessons do not exert a sufficient influence over adolescents’ PA and health (Fairclough & Stratton, 2005). MVPA is performed most often during leisure time, while school sports contribute only marginally to MVPA (Pfitzner et al., 2013). In Finland, a great deal of effort has been set into activating school days, for example, the Finnish Schools on the Move (Haapala et al., 2017). In addition to school PE, to reach adequate levels of PA, children and young people need to participate in PA during the school day and/or during after-school hours and/or in the before-school period. A possible way of promoting PA among youths is to assign PE homework (Gabbei & Hamrick, 2001; Williams & Hannon, 2013; Kääpä et al., 2017). Homework assignments could be designed to practise activities learned earlier at school; to be effective, the practicing should take place during after-school hours. Physical homework provides an opportunity for students to apply and practice the skills learnt in PE lessons (Gabbei & Hamrick, 2001; Williams & Hannon, 2013). According to Kääpä et al. (2017), students can find PE homework enjoyable and beneficial. For example, students enjoyed PE homework that included practicing with family member. In addition, it has been found that Finnish students enjoy participating in planning PE homework (Kääpä et al., 2017). The Finnish National Core Curriculum allows and even encourages the use of leisure time to practice skills learnt during lessons (Finnish National Core Curriculum, 2014). PE homework assignments can be implemented in nearby sporting environments or facilities. Becoming familiar with the physical environment and facilities while undertaking PE homework helps to make PA part of one’s lifestyle (Williams & Hannon, 2013; Smith & Claxton, 2003). The purpose of this study was to examine the objectively measured PA levels of adolescent girls in a lower secondary school in Finland and provide insights into the role of PE homework as part of adolescent girls’ PA. The participants’ MVPA, sedentary time, and the number of total steps and running steps were reported, and compared to PE homework-participation. Using both types of steps and the MET values add variety and reliability to the results and enable comparison between the step-based studies as well. 2. Materials and Methods 2.1. Design of the Study This study is part of the Physical Education Homework Study, a project that began in Finland in 2015. The purpose of the study was to attempt to increase adolescents’ PA time by giving them active PE homework during PE lessons (Kääpä M. Kääpä et al. DOI: 10.4236/ape.2019.94016 226 Advances in Physical Education et al., 2017). This week-long cross-sectional study, conducted in autumn 2016, concentrated on gathering information about adolescent girls’ PA and the role of PE homework by using objective measurements and self-reported methods. 2.2. Participants The participants for this study were girls in the 7th, 8th and 9th grades in a lower secondary school in central Finland. The girls were aged between 12 and 15 years. The half of the girls live near the school and half of them commute to school by buss. From a total of 124 girls, 105 (84.7%) agreed to participate in the study. Girls and their parents were informed about the study beforehand, and informed consent was obtained from the parents/guardians. According to the layer of the University Ethical Board, this protocol covers needed ethical permissions concerning this type of research. The study consisted of week-long objective PA measures using accelerometers and structured self-report diaries during the measurement week. There were missing data from 17 participants as a result of students (12) who were absent from school during the measurement week, and some accelerometer problems that were encountered. The actual study data consists of information from participants who had at least 4 days of accelerometer data ( n = 88) and questionnaires concerning their self-report diaries ( n = 81). In self-reported data, the division was 28 girls from the 7th grade, 26 girls from the 8th grade and 27 girls from 9th grade. In the objectively measured data analysis, to get the most comprehensive overview about the adolescents’ physical activity, all of the participants acceptable (at least 4 days, 10 h minimum/day) accelerometer data were used ( n = 513). For this reason, the measurement days consisted of 190 days of data from the 7th grade girls, 152 days of data from the 8th grade girls and 171 days of data from the 9th grade girls. Girls’ who had both objectively measured and self-reported data were included in analyses of compound measurement results (No PE homework n = 238, PE homework twice a week or more n = 248). 2.3. Setting In Finland, the school day usually begins at 8:00 am and ends at 3:00 or 4:00 pm. The normal school-day structure consists of 7 to 8 lessons lasting for 45-minute each, with a 15-minute break between the lessons and a 30-minute lunch break at noon. The Finnish Schools on the Move program has concentrated on activating students during the school day and using the breaks in an active way (Haapala et al., 2017). The PE Homework Study focuses on activating after-school hours (Kääpä et al., 2017). During the study period, the lower secondary school students had 2 × 45 mins PE lessons in a row (lasting 90 minutes) once a week. In Finland, this double classes one day a week is normal national standard. In Finland, organized after-school sport activities for adolescents usually take place in sport clubs and in teams. According to Blomqvist et al. (2015), over half (53%) of the Finns in their study aged between 9 and 15 took M. Kääpä et al. DOI: 10.4236/ape.2019.94016 227 Advances in Physical Education part in sports-club activities at least once a week. Their participation declined as they aged, with low levels of participation among 15-year-old (Blomqvist et al., 2015). The PE teacher (first author) had occasionally given the girls in the lower secondary school PE homework in past years; thus, the concept of PE homework was familiar to them. PE homework was an aspect of PE that was undertaken by all of the girls. Homework assignments followed PE requirements, and they were given to all students in every PE lesson once a week during the study year. This meant that PE homework was given between 30 and 40 times per school year. PE homework assignments often consisted of body-conditioning exercises such as push-ups, squats or ab crunches; jogging with a family member or friend; stretching; or some skill or activity from the PE lesson. An example of PE homework is balance practices, where the student stands on their right foot in the morning while brushing their teeth and on their left foot at night while brushing their teeth. PE skill practices consisted of tasks practiced in PE lessons that they had to practice for PE homework (e.g., throwing and catching a ball). An example of PE homework combining skill practice and parental involvement is teaching the correct performance of squats to a family member. Involving the students in planning their PE homework was sometimes part of the PE lessons’ “cooling-down” session. Often, the students could choose the scale or complexity of the homework themselves and they had an influence on the activity. Improving the girls’ autonomy and self-determination was the main goal in involving them in planning, choosing the scale and deciding on the amount of PE homework (Deci & Ryan, 2000). Girls participated in their PE homework assignments actively, 89.7% of the girls always completed their PE homework (Kääpä et al., 2017). 2.4. Self-Reported Data The students’ self-reported PA was assessed using a structured diary questionnaire. The aim was to identify the frequency and type of PA that girls engaged in. The diary questionnaire consisted of categorized structures where students marked their activity frequency, level of self-initiated PA, organized sport activities, occupational activities and PE homework in which they participated within the study week. In addition, they estimated the time spent on PE homework. In this study, only self-reported PE homework reports were used. Girls this age are expected to be able to fill out this kind of structured diary that does not require a lot of creativity or writing. Self-reported data supplements the objectively measured data identifying the context of physical activity. 2.5. Accelerometer Data A tri-axial accelerometer, UKK RM42 (UKK-Institute, Tampere, Finland), was selected because of its small-sized and light monitor. It can easily be worn for 24 hours a day and can collect and store data over the course of a week without M. Kääpä et al. DOI: 10.4236/ape.2019.94016 228 Advances in Physical Education needing to be charged. These accelerometers measure accurate information concerning the duration, intensity and pattern of PA and inactive periods, posture and postural changes and the number of total and running steps and enable the comparison of accelerometer results between different studies also in adolescents (Aittasalo et al., 2015). The ability of accelerometers to also record incidental PA is important, as this might be difficult to recall in self-reports, especially for children and adolescents. The accurate information on the metabolic equivalent (MET)-values of PA levels broadens the results from the pedometer’ step counts (Vähä-Ypyä et al., 2015a, 2015b). The time spent standing still, sitting and lying, PA levels and the number of daily steps and running step were categorized separately. The total number of steps includes walking and running steps. Using both types of steps along with the MET values adds variety and reliability to the results. 2.6. Procedures The accelerometerand diary-based measurements were implemented in November 2016, 3 months following the beginning of the semester, meaning that several PE homework assignments had already been completed. The teacher delivered the devices during PE lessons and instructed the girls to wear the flexible (elasticated) belt with the accelerometer around their waist, placing the monitor on the right hip. The teacher gave oral instructions, and written instructions were attached to the diary questionnaire, which was delivered during the same lesson. The girls were instructed to wear the belt for seven consecutive days during their waking hours, apart from during water-based activities such as showering or swimming. The girls started the monitoring straight away and tested the accelerometers; if a malfunction was detected, the device was replaced immediately. The girls returned the accelerometers and their self-report diaries a week later, during their following PE lesson, fulfilling instructed seven consecutive days requirement. To obtain a comprehensive overview, only the data from the participants who used the accelerometer for at least 4 days during the week and at least 10 hours each day were accepted for the study, and the data were analysed in 6-second epochs (Troiano et al., 2008). In studies with large sample, reliability can be achieved with 3 days of recording. Studies with smaller sample sizes like this, it is recommended to measure a greater number of days to improve measurement precision (Mattocks et al., 2008). Monitoring is also recommended to be performed over an entire day (Trost et al., 2000). The average measurement time was 14 hours 30 minutes per day; the minimum time was 12 hours 8 minutes, while the maximum was 19 hours 47 minutes. PE homework was given when the group had their PE lesson; the time period for completing the assigned task was a week. PE homework assignments could be performed at any time during girls’ leisure time, on account of this, the weekdays or weekends were not separated. M. Kääpä et al. DOI: 10.4236/ape.2019.94016 229 Advances in Physical Education 2.7. Analysis The tri-axial acceleration data, collected at a 100 Hz sample rate in raw mode (in g-units), were uploaded and stored, and a statistician from the UKK -institute transferred the data into Excel spreadsheet for further analysis. The collected data were analysed in 6-second epochs and the mean amplitude deviation (MAD) of the resultant acceleration signal was calculated for each epoch (Vähä-Ypyä et al., 2015b). Further, the measured MAD values were converted to MET values in a validated way (Vähä-Ypyä et al., 2015a). MET values were used to categorize PA into different intensity levels: Light PA was defined as activity corresponding to 1.5 - 2.9 METs, moderate activity as 3.0 - 6.0 METs and vigorous activity was more than 6 MET. Body posture was classified as standing, sitting or lying for epochs of low movement intensity (<1.5 MET). The classifications were based on the Angle for Posture Estimation (APE) algorithm, which compares the accelerometer orientation in relation to an identified upright position at the end of each 6-second epoch (Vähä-Ypyä et al., 2018). The analyses were implemented using SPSS software. The recorded PA levels and sedentary time of each girl from the measurement days were compared. Means and standard deviations in light, moderate, vigorous and MVPA MET values, along with standing and sedentary behaviour (i.e., sitting and lying) were analysed using analysis of variance (ANOVA) and Tamhane’s post-hoc test. The MET values were smoothed by calculating a 1-minute exponential moving average for each epoch; the peak hourly MET value was analysed from the smoothed MET values. In addition, the mean values and standard deviations from the number of average total and running steps per day of the girls from the 7th, 8th and 9th grades were compared by means of ANOVA and Tamhane’s post-hoc test. An ANOVA and Tamhane’s post-hoc test were used to compare the 7th, 8th and 9th graders in terms of their self-reported data on the frequency and time spent doing their PE homework. The girls were further divided into 2 PE homework groups: Those who did not do PE homework at all or did it only once a week and those who did it at least twice a week. Independent-sample T-tests were used to compare two groups’ daily running and total steps with the objectively measured PA levels. For the independent-samples t-tests, Cohen’s d was determined by calculating the mean difference between the two groups and then dividing the result by the pooled standard deviation. Cohen’s d is the appropriate effect -size measure when 2 groups have similar standard deviations and are of similar size, as in these data. The significance level was set at p < 0.05. 3. Results 3.1. Physical Activity Levels The participants’ objectively measured and combined light, moderate and vigorous average PA time of the participants was 4 hours 18 minutes (SD ± 1 hours 6 minutes). The light PA coverage of 3 hours 8 minutes (±40 minutes) was transcendent compared to a moderate-to-vigorous coverage of 1 hour 2 minutes M. Kääpä et al. DOI: 10.4236/ape.2019.94016 230 Advances in Physical Education (±20 minutes) and 8 minutes (±6 minutes) of vigorous PA per day (Table 1). The average measurement time per day was comprehensive, 14 hours 30 minutes, and the average sedentary time was 7 hours 37 minutes (±1 hour 52 minutes), representing 52% of the total measurement time. The participants spent an average of 2 hours 41 minutes (±55 minutes) standing still, 6 hours 29 minutes (±1 hour 5 minutes) sitting and 1 hour 8 minutes (±1 hour 5 minutes) lying down on each measurement day. The 7th graders recorded greater levels of daily light PA than those from other grades. The 7th grade girls recorded an average daily light PA time of 3 hours 28 minutes (±32 minutes); this is 34 minutes more than the girls from 8th grade ( p = 0.000) and 30 minutes more than the girls from the 9th grade ( p = 0.000). Regarding daily moderate PA, there was a significant difference between the girls from the 7th and 8th grades ( p = 0.017), with a 6-minute time differential benefitting the 8th graders. The half of the girls from the 8th grade reached the Finnish 60-minute PA recommendation; 38% of all girls met the recommended levels of PA. For the 7th grade girls, 35% met the recommendations, while 28% of the 9th grade girls reached the 60-minute PA recommendations every day. The 9th grade girls spent more time standing than others. There was a significant difference in time spent standing between the girls from the 7th and 9th grades ( p = 0.038), with a 12-minute differential between these grades. Regarding sedentary behaviour (i.e., sitting and lying), the girls from the 8th Table 1. Participants’ daily average time (hours and minutes) spent in different physical activity (PA) levels, including combined level of moderate and vigorous physical activity (MVPA), by grades (mean, std. deviation, ANOVA p -value and Tamhane’s post-hoc test). 7th grade (190 days) 8th grade (152 days) 9th grade (171 days) All (513 days) All Post-hoc Mean (SD) Mean (SD) Mean (SD) Mean (SD) ANOVA p - value 7-8th grade 7-9th grade 8-9th grade Light PA (1.5 - 2.9 MET) 3:28 (0:32) 2:54 (0:36) 2:58 (0:42) 3:08 (0:40) 0.000 0.000 0.000 0.834 Moderate PA (3 - 6 MET) 0:59 (0:16) 1:05 (0:23) 1:03 (0:21) 1:02 (0:20) 0.016 0.016 0.193 0.656 Vigorous PA (over 6 MET) 0:08 (0:07) 0:09 (0:06) 0:08 (0:06) 0:08 (0:06) 0.110 0.317 0.937 0.098 MVPA 1:08 (0:40) 1:15 (0:43) 1:11 (0:40) 1:11 (0:41) 0.283 0.315 0.864 0.755 Time spent standing 2:36 (0:47) 2:38 (1:02) 2:50 (0:57) 2:41 (0:55) 0.041 0.915 0.030 0.287 Time spent sitting 6:30 (1:05) 6:31 (1:07) 6:25 (1:04) 6:29 (1:05) 0.667 10.000 0.782 0.864 Time spent lying 1:19 (1:13) 0:41 (0:35) 1:20 (1:08) 1:08 (1:05) 0.000 0.000 10.000 0.000 Total sedentary (sitting and lying) 7:51 (2:01) 7:11 (1:18) 7:45 (2:02) 7:37 (1:52) 0.003 0.001 0.970 0.008 M. 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