Academic Performance of Texas Public Schools and Its Relationship with Students' Physical Fitness and Socioeconomic Status

Introduction

According to U.S. Department of Health and Human Services, approximately half of youths who are aged 12-21, are physically inactive in daily life (US Department of Health and Human Services, 2009). The prevalence of physical inactivity and sedentary habit among youth may result in bad consequences for children’s health (Castelli, Hillman, Buck, & Erwin, 2007; Strong et al., 2005). For example, physical inactivity may lead to low level of physical fitness, which may contribute to an elevated risk for health issues, including obesity, cardiovascular diseases, and type 2 diabetes (Minck, Ruiter, Van Mechelen, Kemper, & Twisk, 2000; Ondrak, McMurray, Bangdiwala, & Harrell, 2007; Warburton, Nicol, & Bredin, 2006). In addition, being physically inactive has adverse effect on mental health, such as depression, anxiety, stress, and self-esteem (Centers for Disease Control, 2008; P. A. Liao, Chang, Wang, & Wu, 2013). Therefore, it is important to advocate physical activities in adolescence, aiming at improving physical fitness and reducing the risks of chronic diseases in adulthood (Eveland-Sayers, Farley, Fuller, Morgan, & Caputo, 2009; P. A. Liao et al., 2013; Must, Jacques, Dallal, Bajema, & Dietz, 1992). Physical fitness, usually positively correlate with physical activity (Strong et al., 2005), is defined as a set of attributes that people achieved when they have the ability to perform physical activity (Caspersen, Powell, & Christenson, 1985); it is the health outcome of physical activity. Physical fitness has five components: body composition, cardiovascular fitness, muscular strength, muscular endurance, and flexibility (Coe, Peterson, Blair, Schutten, & Peddie, 2013; Svien, 2003).

Higher levels of physical fitness are often associated with better academic achievement (Bass, Brown, Laurson, & Coleman, 2013; Castelli et al., 2007; Dwyer, Sallis, Blizzard, Lazarus, & Dean, 2001; Janak et al., 2014; London & Castrechini, 2011; Stevens, To, Stevenson, & Lochbaum, 2008; Tremblay, Inman, & Willms, 2000; Van Dusen, Kelder, Kohl, Ranjit, & Perry, 2011). In other words, physical fitness is commonly found to be positively associated with academic performance and students who are physically fit tend to have better academic performance. For example, an assessment by Eveland-Sayers et al. (2009) on 3^rd-, 4^th-, and 5^th-graders found a positive association between muscular fitness and Math scores. Fox, Barr-Anderson, Neumark-Sztainer, and Wall (2010) extended the study to middle and high schools, and found a positive relationship between physical activity and academic achievement. These findings are important in practice since they suggest that the efforts to promote physical fitness in schools may help improve learning outcomes.

However, few studies have examined the relationship between students’ physical fitness and their academic performance at a school-district scale. In addition, despite that socioeconomic status (SES) has been found to be associated with both academic performance and physical fitness (Freitas et al., 2007; Kim et al., 2003; Sirin, 2005), the existing findings did not consider the effect of SES on the relationship between physical fitness and academic performance. Furthermore, the existing studies assumed that the association between physical fitness and academic performance are consistent across the study area, neglecting spatial non-stationarity of the association. Exploration of the spatial variation of the relationship between physical fitness and academic performance is missing in literature.