Study results have been inconclusive thus far, although all indicate that participation in PE is not harmful to student achievement (Blom et al. 2011: 13). But while fitness levels and academic achievement have shown to be consistently linked, studies which attempt to track student improvement have occasionally yielded surprising results, such as showing increases in academic performance for boys but not for girls. "Inconsistencies in physical education instruction and curriculum and variations in the amount of time spent in moderate to vigorous activity during class may contribute to the discrepancies in the results" (Blom et al. 2011: 13). Also, the fitness state of participants before the study can influence results. Girls tend to be less active than boys and thus could have shown more notable gains. Race and socio-economic status may also influence results, given that students of disadvantaged backgrounds may have fewer opportunities to play outside of school or access to healthy foods, which could mitigate the positive impact of PE.

The specific study of the researchers in the article focused on students in grades 3-5. The study sample was 52.4% male, 52.3% white, the majority of the participants were within a healthy weight range (54.1%), and qualified for free/reduced price lunch (63.7%). "Participants' overall fitness level was determined by the number of healthy fitness zones they achieved on the test battery, ranging from zero to six" on the Cooper Institute Fitnessgram (Blom et al. 2011: 14). Student's academic achievement was assessed based upon performance on the Mississippi Curriculum Test (MCT2) and absentee rates. When controlled for race, ethnicity, socio-economic status and gender, a significant positive correlation was found between fitness and "standardized test scores in both Language Arts and Math. For Language Arts, the likelihood of high academic achievement increased with each additional fitness zone achieved (up to three times); for Math, a similar trend was found" (Blom et al. 2011: 14).

The findings of this study challenge the commonly-raised concern that PE 'takes away' from time better spent on academics and standardized test preparation. The scope of the research study did not attempt to answer why there might be such a positive correlation between fitness and academic achievement. However, the researchers believed that there was sufficient evidence to recommend continued inclusion of PE in the middle school curriculum and/or to develop partnerships with community organizations such as the YMCA that could provide facilities for aerobic activity to improve student health. Students of color and from disadvantaged backgrounds were targeted as being in particular need of structured physical activity, given that they are at greater risk for obesity and poor school performance and attendance. The study authors recommend that PE classes focus on high-quality movement rather than duration of time alone and that student physical fitness should be consistently monitored throughout the child's schooling, not simply during the middle grades (Blom et al. 2011: 14).