Within the context of school-based physical education (PE), a strength and conditioning program called CrossFit Kids (CFK) has emerged as a potential intervention for positively impacting students. The purpose of this study was to evaluate through a randomized-controlled trial how academic and health-related fitness outcomes differed for middle school students (age = 12.73; 55.3 % male) who participated in a school-based CFK program (n=72) as compared to a group of students who participated in PE class (n=72). Questionnaire data were collected twice across the 9-month academic year and combined with FitnessGram and grade data.

Students in both the intervention and comparison groups increased in health-related fitness outcomes (all p values < .017), and there was a significant treatment group by time interaction on school-reported grades [F(1, 124) = 7.270, p = .008, η_P^2 = .055].

Significant gender by time interaction effects were found for the relationship between CFK or PE participation and health-related fitness outcomes, but there were no significant interaction effects by gender on academic outcomes. Because developmental outcomes are conditional and result from the coaction of many factors, the findings suggest that some elements of CFK might be beneficial to build skills yet disadvantageous to academic outcomes.

在以学校为基础的体育教育 (PE) 的背景下，一项名为 CrossFit Kids (CFK) 的力量和调节计划已成为对学生产生积极影响的潜在干预措施。本研究的目的是通过随机对照试验评估参加基于学校的 CFK 计划（n=72）的中学生（年龄 = 12.73；55.3 % 男性）在学业和健康相关的健康结果方面有何不同与参加体育课的一组学生 (n=72) 相比。在 9 个月的学年中两次收集问卷数据，并结合 FitnessGram 和成绩数据。

干预组和对照组的学生在健康相关的健康结果方面都有所增加（所有 p 值 < .017），并且在学校报告的成绩上存在显着的时间交互作用的治疗组 [F(1, 124) = 7.270, p = .008，η_P^2 = .055]。

对于 CFK 或 PE 参与与健康相关健身结果之间的关系，发现了显着的性别按时间交互作用，但性别对学业结果没有显着的交互作用。由于发展成果是有条件的，是许多因素共同作用的结果，因此研究结果表明，CFK 的某些要素可能有利于培养技能，但对学术成果不利。