Understanding the impact of the school environment on physical activity (PA) levels is beneficial in creating health promotion strategies; targeting students of varying levels of physical fitness. One way to encourage lifelong participation in PA among adolescents is through Physical Education (PE) class. For adolescents who do not participate in sport, or engage in PA outside of school, PE may play a crucial role in keeping them active. The purpose of this study was to examine adolescents’ health profiles and gain an understanding of adolescents’ perspectives of PE with intentions to utilize the results to provide PE as a viable option of PA.
The PA guideline for adolescents across Canada and the United States of America is 60 minutes per day (Canadian Society for Exercise Physiology, 2013; U.S. Department of Health & Human Services, 2013) . This amount of PA can help adolescents grow stronger, feel happier, maintain a healthy body weight, improve self-confidence, and learn new skills (Canadian Society for Exercise Physiology, 2013) . Additionally, adolescents who engage in PA, have lower body fat (Nassis, Psarra, & Sidossis, 2005) , lower chance of cardiovascular disease (Andersen, Harrow, Sardinha, Froberg, Ekelund, Brage & Anderssen, 2006) , higher self-es- teem, greater social skills, lower chance of engaging in health risk behaviors (Aaron, Dearwater, Anderson, Olsen, Krisak, & LaPorte, 1995) , and higher academic achievement (Coe, Pivarnik, Womack, Reeves, & Malina, 2006; Public Health Ontario, 2010) . Conversely, physical inactivity increases chances for 25+ chronic illnesses, including overweight and obesity, and some cancers (Booth & Lees, 2007) . Conversely, adolescents who succumb to physical inactivity are at a higher risk for obesity (Sallis & Patrick, 1994) , a variety of cardiovascular risk factors (Sallis & Patrick, 1994; Camhi, Phillips, & Young, 2010) , and developing osteoporosis later in life (World Health Organization, 2004) . To put this into perspective, in 2007 chronic illnesses were responsible for 75% of all deaths in Ontario (Active Healthy Kids Canada, 2012).
The aforementioned benefits present concern when the following data are considered. Time spent engaging in moderate to vigorous physical activity (MVPA) declined among females from early to mid-adolescence (5.9 - 4.9 hours/week) to mid- to late-adolescence (5.1 - 3.5 hours/week) (Nelson, Neumark-Sztainer, Hannan, Sirard, & Story, 2006) . Results also showed males’ participation showed significant declines from mid- to late-adolescence (6.5 - 5.1 hours/week). Moreover, as a potential result of declining PA rates, the presence of overweight status among adolescents has risen in males from 14% (1999-2000) to 18.2% (2003- 2004) and females from 13.8% (1999-2000) to 16.6% (2003-2004) (Hedley, Ogden, Johnson, Carroll, Curtin, & Flegal, 2004) . More recently, research has shown 19.8% of Canadians 5 to 17 years of age (Statistics Canada, 2010) and 33.2% of Americans 6 to 19 years of age (Fryar, Carroll, & Ogden, 2014) are considered overweight or obese. When data is compared from 1978/1979 to 2004 for Canadians 2 to 17 years of age considered overweight or obese, the prevalence has increased from 15% to 26% (Public Health Agency of Canada, 2012) . In addition, World Health Organization (2015) forecasts that youth who are overweight or obese will likely continue to be overweight or obese as adolescents and adults if an intervention is not presented.
While studies report an overall decline in PE enrollment for high school students in Ontario (Table 1) (Faulkner, Goodman, Adlaf, Irving, Allison, & Dwyer, 2007; Hobin, Leatherdale, Manske, Burkhalter, & Woodruff, 2009) , 77.7% - 86.6% students who do enroll in PE are meeting the recommended 150 minutes of MVPA per week as per suggestions through the PE curriculum (Dwyer et al., 2006) ; which further identifies the school as an effective environment for PA. For students who do not participate in sport, or engage in PA outside of school, PE may play a crucial role in keeping them active. Fishburne and Hickson (2005) define PA as the expenditure of energy as a result of bodily movement and emphasizes the important role it plays in the PE curriculum by providing students with a chance to practice and improve a variety of motor skills. The main intention of PE courses in Canada is to assist students in shaping their health behaviours (Gibbons, 2009) , by developing skills, and attitudes, vital for engaging an active lifestyle (Fishburne & Hickson, 2005) .
The potential to increase PA levels through PE identifies the school environment as a convenient place to promote healthy behaviours for adolescents (Wechsler, Devereaux, Davis & Collins, 2000; Biddle, Gorely & Stensel, 2004; Public Health Ontario, 2010) . Physical Education class is a consistent opportunity for students to engage in MVPA (Faulkner et al., 2007) , meet Canadian PA recommendations (Trudeau & Shephard, 2008) , and increase PA levels in general (Hobin et al., 2010) .
However, the few studies that have observed adolescents’ attitudes toward PE uncovered that both males and females negatively viewed long bouts of running, fitness testing, and coeducational classes (Luke & Sinclair, 1991) . When students believed their class promoted competition with too much focus on their mistakes, they were less likely to enjoy class (Ferrer-Caja & Weiss, 2000) . Some males disliked PE because they felt they were unfit, unhealthy, and could not keep up with the class (Luke & Sinclair, 1991) . Moreover, females felt embar-
Table 1. PE enrollment rates in Ontario: 1999-2006.
rassed, self-conscious, pressured, and began disliking PE when they started being evaluated on their athletic ability (van Daalen, 2005).
Although adolescents’ PA levels and PE enrollment are declining, there are some PE classes with high enrollment rates and positive student feedback. Research on successful female PE classes suggested designing different courses to specific populations of students, assessing students on tasks that would be performed in real-world settings, and fostering a safe and healthy learning environment (Gibbons, 2009) . Furthermore, research on both genders found when students feel their success is attainable through hard work and an interest in learning, they feel more invested in the PE class as they understand they have control of their achievement (Standage, Duda, & Ntoumanis, 2003) . In order to identify the issues surrounding adolescent’s participation in high school PE class the current multi-dimensional study was conducted.
The purpose of this study was: 1) to identify adolescents’ PE rating among other subjects and identify it as a predictor of PA levels and health variables longitudinally; 2) to identify the relationship of Non-School-Based PA and health variables longitudinally; 3) to identify changes in health variables longitudinally; and, 4) to gain insight on adolescents’ perspectives of PE.
This study utilized a mixed methodology and was completed in two parts. Part 1 addressed components 1 through 3 using quantitative analyses of data from the National Longitudinal Survey of Children and Youth (NLSCY) as conducted by Statistics Canada (Appendix A). Part 2 addressed component 4 through qualitative analyses of focus groups conducted at high schools within Windsor-Essex County, Ontario, Canada. Research Ethics Board approval from the University of Windsor was obtained, and participant consent and parental consent were obtained for Part 2 of this study.
Participants. Participants from Cycle 7 (C7) were Canadian adolescents (range = 12 - 15 years, M = 13.64 years, SD = 1.15), and participants from Cycle 8 (C8) were the same adolescents two years later (range = 14 - 17 years, M = 15.72 years, SD = 1.16). The overall sample size was 4963 (males = 51.6%, females = 48.4%); however, due to differences in the questions included in Cycles 7 and 8, the final samples for analyses ranged from 1713 to 4.82.
Instruments. The NLSCY is a longitudinal study conducted by Statistics Canada (2010) with the goal of observing the development of Canadians from infancy to adulthood. Data from Cycle 1 was collected in 1994/1995 and data has been collected every two years until Cycle 8 in 2008/2009. The participants in the NLSCY were selected from households that were already being sampled by Statistics Canada’s Labour Force Survey (Statistics Canada, 2010) . The NLSCY gathered self-reported data on factors influencing a child’s social, emotional, and behavioural development and to monitor the impact of these factors on a child’s development over time. Specifically, this data were derived through a self-com- pleted paper questionnaire of participants between the ages of 12 and 17 years across Canada. The questionnaire was self-completed, sealed in an envelope to ensure confidentiality, and returned to the interviewer (Statistics Canada, 2010). At the time of data analysis, data from C7 and C8 were not available on a public use micro data file and approval from Statistics Canada was obtained.
Five health behaviors and outcomes from C7 and C8 were examined as dependent variables: NSBPA (range = 3 - 12), School-Based PA (SBPA) (range = 3 - 12), BMI (range = 1 - 3), “I like the way I look” (range = 1 - 5) and Health Status (range = 1 - 5).
Data Analyses. Multiple regression analyses were used to determine if PE rating and C7 NSBPA separately predicted NSBPA, SBPA, BMI, and “I like the way I look” from C8. The standardized coefficient, Beta (β), value was used to indicate how many standard deviations the outcome variables changed when the predictor variable increased by one standard deviation; this value is also representative of the effect size.
To determine a change in health behaviors over two years, the Wilcoxon signed- rank test was used to compare C7 to C8. Variables of interest included: NSBPA, Health Status, “I like the way I look”, and BMI. For these tests, effect sizes (r) were calculated to determine the power of the relationship. This was done by dividing the Z-value by the square root of N (Cohen, 1988) .
IBM Statistics Package for the Social Sciences (SPSS) 20 was used for all data analysis (IBM Corp, 2011) .
Participants. Thirty two high school students including males (n = 13) and females (n = 19) (range = 14 - 19; M = 15.63, SD = 1.72) participated in Part 2. Focus groups consisted of 7 to 9 students, and were separated into grade 9 (n = 2 focus groups) and grade 11/12 (n = 2 focus groups). Students had enrolled in high school PE at least once to meet the mandatory Ontario provincial requirements of one credit and were randomly selected on a volunteer basis through the principals and PE departments within the Greater Essex County and Windsor- Essex Catholic district school boards.
Instruments. A semi-structured question guide (Appendix B) was prepared by the researcher after a thorough review of literature and meetings with members of the local school board. Inventories were also developed with a list of potentially influential factors to students’ PE experiences to stimulate discussion.
Procedure. Focus groups were moderated by the researcher and were 75 minutes in length. Each session began with less structured questions that introduced the topic of PE and progressed into more specific questions (Kruger, 1998a) .
Data analyses. First, the audio recordings of each focus group were transcribed verbatim. Following previous work (Kruger, 1998b; Tesch, 1990) , interviews were separated into meaning units that highlighted relevant information within and across focus groups. In order to discover prevalent themes from the data, similarities, differences, and repetitions were identified (Ryan & Bernard, 2003) . Some categories were combined to strengthen data groupings and the importance of each category was considered based on information most useful for promoting health behaviors among adolescents.
Physical Education rating. When the PE rating variable (M = 2.61, SD = .76) was constructed, frequencies showed, 17.0% preferred other subjects over PE, 4.9% tied between other subjects and PE, and 78.1% preferred PE over other subjects. Females (M = 2.47, SD = .853) rated PE lower when compared to males (M = 2.75, SD = .626) (Table 2). Multiple regression analyses showed PE rating significantly predicted NSBPA [R2 = .019, F(11,1762) = 3.165, p < .05], SBPA [R2 = .048, F(11,2082) = 9.582, p < .05], BMI [R2 = .018, F(11,3331) = 5.441, p < .05], and the “I like the way I look” variable [R2 = .041, F(11,3528) = 13.827, p < .05] in C8 (Table 2). Therefore, if participants preferred PE over other subjects they reported a higher frequency of PA per week, lower BMI, and a more favorable “I like the way I look” rating two years later.
Cycle 7 Non School Based Physical Activity. Frequencies showed overall mean NSBPA decreased from C7 to C8, and when NSBPA was deconstructed, the mean for each NSBPA variable also decreased from C7 to C8 indicating that it was not a single variable responsible for overall mean decrease (Figure 1). Multiple regression analyses identified C7 NSBPA as a significant predictor for C8 NSBPA [R2 = .213, F(11,1792) = 44.154, p < .05], Health Status [R2 = .066, F(11,1820) = 11.689, p < .05], BMI [R2 = .038, F(11,1702) = 6.169, p < .05], and “I like the way I look” [R2 = .062, F(11,1828) = 10.992, p < .05] (Table 3). This
Table 2. PE rating predicting NSBPA and SBPA.
Table 3. C7 NSBPA predicting NSBPA and health status.
Figure 1. Means for NSBPA with standard error bars.
indicates, if participants reported higher frequencies of NSBPA per week in C7 they reported higher frequencies of NSBPA per week, higher Health Status, lower BMI, and a more favorable “I like the way I look” rating in C8. It should be noted that the relationship between C7 and C8 NSBPA was the most positive relationship through the multiple regression analyses inferring that if participants engaged in NSBPA in C7 they were more likely to engage in NSBPA two years later in C8.
Health variables. Wilcoxon signed rank tests showed significant change between NSBPA, Health Status, BMI, but not “I like the way I look” (Table 4). Participants had lower levels of NSBPA in C8 when compared to C7. Health Status and BMI can be explained by the concept that a higher number of participants changed their score by more than one value in the direction of a negative health outcome, and fewer participants changed their score by one in the direction of a positive health outcome. For example, a higher number of participants went from Normal Weight to Obese, compared to a lower number of participants who went from Obese to Overweight or Overweight to Normal Weight.
Table 4. Medians and standard deviations for Wilcoxon signed-rank variables.
r represents effect size.
Focus group data analyses yielded multiple themes: class environment, gender differences, course conflict, and students’ suggestions. Of these themes, teacher influence within class environment and course conflict were among the most heavily discussed. These themes also consisted of different meaning units repre- sented by quotes from the focus group sessions (Table 5).
Class environment. Participants identified that the class environment was highly influential to their PE experience and consisted of: the physical and social environment, participation and personalities, teacher influence, and evaluation. All participants agreed that when a teacher participated and/or showed interest in the course the students felt more motivated and excited about the class. Overall, participants indicated a heavy emphasis on teacher influence as a deciding factor for whether they wanted to enroll again or not.
Gender differences. Females who had previously identified themselves as athletic suggested that co-ed classes did not bother them because it gave them an opportunity to be challenged. Most females also agreed that it was fun to mix once in a while but they would generally prefer a same-sex class because males were viewed as overly competitive. Females enjoyed the openness of same-sex PE because it gave them an opportunity to ask questions throughout the health unit without feeling judged by their male schoolmates; whereas males wished it was a separate course.
Course conflicts. Course conflicts were discussed as a highly influential barrier of PE enrollment across all participants. Many participants who wished to take PE indicated that they did not have room in their schedule due to prerequisites for future classes. Prerequisites were identified as necessary not only for senior years of high school but for university acceptance. Physical Education was beneficial for getting active but was not considered useful, relevant, or practical, in comparison to other courses. With limited timetable space in grade 10, students were forced to choose carefully between many options. This theme was consistently agreed upon and had a large influence on students’ future enrollment.
Students’ suggestions and insight. Across all focus groups, participants made suggestions for what may increase PE enrollment. Participants discussed
Table 5. Focus group quotes.
the idea of competitive versus non-competitive classes, different activity options (e.g., self-defense and yoga), field trips, specialized guest instructors, and more activity choices. It was suggested that more students may enroll if they know they would be accompanied by other students who were interested in the same activities as them and are not overly competitive. Furthermore, participants from different focus groups suggested conducting a survey in which teachers could obtain an idea of what activities to include in the course. Lastly, when participants were asked what they would emphasize if their job was to get students to enroll in PE, they agreed that learning to be active is something that they can use for the rest of their lives.
This study aimed to identify the relationship between PE rating, NSBPA, a variety of health variables, and adolescents’ perspectives of PE at the secondary school level. Although PE rating is a predictor of NSBPA and both longitudinally predict a variety of health variables, Canadian adolescents are engaging in less NSBPA as they age. Adolescents preferred PE over other subjects (78%), which suggested greater NSBPA levels, lower BMI, and higher self-esteem, but PE enrollment continues to decline (Dwyer et al., 2006; Faulkner et al., 2007; Hobin et al., 2009) .
Consistent with previous research, PE rating and C7 NSBPA predicts lower BMI (Datar & Sturm, 2004; Camhi, Phillps, & Young, 2010) and self-esteem (Luke & Sinclair, 1991) . Depending on the structure of the class, PE may be a negative experience in which students are exposed by their lack of ability leading to negative perceptions (Luke & Sinclair, 1991; Gibbons, 2009; Allison, Dwyer, Goldenberg, Fein, Yoshida, & Boutilier, 2005; Bauer, Yang, & Austin, 2004) . Focus group results explored the suggestions of having classes which are divided by level of competition. This finding is similar to previous research suggesting students prefer to compete against themselves rather than peers and avoid pursuing PA opportunities where overly competitive peers would be present (Allison et al., 2005) . This suggestion gives students who are less skilled an opportunity to participate with others of similar skill level. Participants also suggested the class environment should be an avenue students can enjoy themselves and show support and encouragement. The social environment is important as many students indicated they enjoyed the opportunity to spend time with friends; which is supported by previous research on PA (Allison et al., 2005) and PE (Bauer et al., 2004) . The predictive nature of C7 NSBPA with C8 NSBPA emphasizes the importance of creating a positive experience with PA, potentially through PE, early in adolescence. This study also identified that adolescents are generally less active, which is supported by research suggesting as age increases PA levels decrease (Active Healthy Kids Canada, 2012; Camhi et al., 2010) . It is alarming to consider that this trend may persist and they will become less healthy into adulthood.
While the quantitative data suggest that PE is the preferred academic subject, and that participation in PE is related to healthy behaviours it is puzzling why PE enrollment decreases. One of the most influential factors discussed, were teachers’ influences on the PE experience (Luke & Sinclair, 1991; van Daalen, 2005; Gibbons, 2009) . Students spoke highly of teachers who were outgoing and encouraged goal setting. Moreover, students felt that if the teacher was disengaged, authoritarian, and did not give positive feedback; they did not have an enjoyable experience.
Students identified other courses in their schedule as a barrier to PE enrollment. Students either wanted to take other courses to explore potential careers or needed specific courses as prerequisites for university. While PE was considered less useful when compared to other options; some students agreed courses could be replaced by PE. Whether the decision was driven through curiosity, academic pressure, or parental pressure (Hobin et al., 2009; Allison et al., 2005) , students’ schedules did not always allow for PE. Overall, students identified having greater variety and the opportunity to contribute their input as positive contributors to the PE experience (Luke & Sinclair, 1991; Gibbons, 2009) .
Due to the inconsistency of questions asked from C7 to C8, it was not possible to analyze a potential link between PE and SBPA, or a change in SBPA levels. Self- report may also present a limitation as participants are asked to identify their own PA levels and health related responses. Also, although participants generally spoke freely about their PE experiences, participants may have abstained from delving deeper into their personal opinions during focus groups.
Physical Education is an avenue for PA; it has predictive ability with PA and health variables, and there is mass preference for PE. The use of PE rating as a predictor variable is a unique contribution to the literature. PE rating predicts positive health outcomes and highlights that students in fact enjoy PE classes. Despite the affinity for PE students display, enrollment is declining.
School provides a safe, controlled and inclusive environment for all students despite their family influences (Faulkner et al., 2007), socioeconomic status, gender, and race (van Daalen, 2005) . The importance of the school environment in influencing health behaviours among adolescents is not a new development. School plays a vital role in promoting PA and shaping health behaviours to carry into adulthood; specifically PE is a good predictor of tracking PA from adolescence into adulthood (Trudeau, Laurencelle, Tremblay, Rajic, & Shephard, 1999) . The school environment should be taken advantage of by health advocates, administrators, educators, parents, and students on the quest for a healthier lifestyle. High school students who attend PE class regularly reported healthier eating behaviours (e.g. higher intake of fruit and vegetable, and lower intake of soda) and less time spent watching television during the week (Tassitano, Barros, Tenório, Bezerra, Florindo, & Reis, 2010) .
Given the popularity of PE over other subjects, PE continues to be a viable avenue to promote PA (Public Health Ontario, 2010) . Physical Education is free of charge, will afford students with high school credits, and can be provided as a regular part of their semester. More importantly, it is a class in which students can engage in PA, learn about health related topics, and develop new skills. These additional topics, such as but not limited to: sexual health, mental health, and healthy relationships are not found elsewhere in the secondary school curriculum and would be an added bonus to the benefits that the adolescents would receive by engaging in PA in a structured and safe environment. Overall, there is a potential chain reaction that begins in early adolescence through PE experience and PA levels. This chain reaction can be negative or positive depending on adolescents’ enrollment in PE and frequency of participation in PA. This does not imply that students should not enjoy other subjects taught in the school system, but PE courses should be considered an important part of the educational experience.
Adolescence is a highly influential time to shape healthy habits and facilitate positive health behaviours. As we know, adolescents spend majority of their time at school which suggests it is an influential environment (Besançon, Fenouillet, & Shankland, 2015) . Schools can make individual changes to influence adolescents’ physical activity (PA) levels to accommodate for the declining Physical Education (PE) enrollment through utilizing themes from this study. Administration, department heads, and teachers can consider what can be done to bridge the gap between the benefits of PA through PE and the students who do not wish to enroll. A further understanding of what prevents students from enrolling in PE will provide groundwork in moving forward with PE promotion.
Kelly Carr, PhD Candidate, Department of Kinesiology, University of Windsor. Dan Edelstein, Data Specialist, University of Windsor. Kristy Thompson, Data Specialist, University of Windsor. Dr. Nancy McNevin, Professor, Department of Kinesiology, University of Windsor. Windsor Essex Catholic District School Board, Windsor, Ontario. Greater Essex District School Board, Windsor, Ontario. Canadian Society for Psychomotor Learning and Sport Psychology Conference (2013), Kelowna, British Columbia
Appendix A. Glossary of Terms
National Longitudinal Survey of Children and Youth (NLSCY)―is a long- term study of Canadian children that follows their development and well-being from birth to early adulthood. The study is designed to collect information about factors influencing a child’s social, emotional and behavioural development and to monitor the impact of these factors on the child’s development over time (Statistics Canada, 2010) .
Cycle 7―NLSCY completed from September 2006 to July 2007.
Cycle 8―NLSCY completed from September 2008 to July 2009.
Non-School-Based Physical Activity (NSBPA)―Physical activity outside the school environment. Within this study, this variable consisted of physical activity outside of school, within the past 12 months, without a coach/instructor, with a coach/instructor, and physical activity through groups/lessons.
Physical Activity (PA)―the expenditure of energy as a result of bodily move- ment (Fishburne & Hickson, 2005) .
Physical Education (PE)―a school-based subject created to assist students in development of skills, knowledge, and attitudes vital for participation in active and healthy living (Fishburne & Hickson, 2005) .
PE Rating―participants rating of PE in comparison to Math, Science, English, French and Arts.
School-Based Physical Activity (SBPA)―Physical activity within the school environment, but outside of Physical Education class. Within this study, this variable consisted of school based physical activity, since the beginning of the year, without a coach/instructor, with a coach/instructor, and physical activity through groups/lessons.
Appendix B. Semi-Structured Question Guide
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