Milanese Chiara, Sandri Marco, Cavedon Valentina, Zancanaro Carlo
Laboratory of Anthropometry and Body Composition, Department of Neurosciences, Biomedicine and Movement Sciences, University of Verona, Verona, Italy.
PeerJ. 2020 Mar 17;8:e8657. doi: 10.7717/peerj.8657. eCollection 2020.
The determinants of physical fitness in children have been given limited attention. In particular, the relative role of chronological age, sex, anthropometry, and body composition in physical fitness of children has been barely investigated. This cross-sectional study investigated determinants of physical fitness using a set of predictive variables including, in addition to chronological age and sex, a large panel of anthropometric measurements as well as body composition. The study was carried out in a convenience sample of children aged 6-12 participating in a summer camp.
One-hundred-ninety-three children (128 males) fulfilled all requirements and entered analysis. Health-related physical fitness components (speed, muscular power and balance) were explored by means of field tests, namely the 30-m dash test for running speed, the standing long jump and the seated chest pass test for lower limbs and upper body muscular power, respectively, and the flamingo balance test for static balance. Determinants of physical fitness were investigated by regression analysis using chronological age, sex, anthropometry, and body composition in a hierarchical approach. To minimize the expected effect of collinearity in predictor variables, an original statistical approach using Random Forests analysis was adopted.
Age predicted 45.2%, 43.6%, 35.6% and 25.6%; and sex 9.5%, 10.7%, 6.3% and 2.0% of variance in the 30-m dash, seated chest pass, standing long jump, and flamingo balance test, respectively. Anthropometry and body composition explained a limited or no percentage of variance. The adjusted (root mean square error) was 0.61 (0.31 s), 0.45 (0.32 m), 0.58 (0.15 m) and 0.41 (0.75 logs) for the 30-m dash, seated chest pass, standing long jump, and flamingo balance test, respectively making these models useful when physical fitness tests are not feasible.
We highlighted the respective role of chronological age, sex, anthropometry, and body composition in physical fitness of children in the wide age range 6-12 years. Data confirm and expand on previous literature by showing with a strictly conservative statistical approach that chronological age is a main determinant of physical fitness of both boys and girls, sex playing a limited role. The role of anthropometry was even less important, and no role was found for body composition. These findings should be considered when planning/implementing motor development or physical education programs.
儿童体能的决定因素受到的关注有限。特别是，实足年龄、性别、人体测量学和身体成分在儿童体能中的相对作用几乎未被研究。这项横断面研究使用了一组预测变量来调查体能的决定因素，除实足年龄和性别外，还包括大量人体测量指标以及身体成分。该研究在一个参加夏令营的6至12岁儿童的便利样本中进行。
193名儿童（128名男性）满足所有要求并进入分析。通过现场测试来探究与健康相关的体能成分（速度、肌肉力量和平衡能力），即通过30米短跑测试跑步速度，分别通过立定跳远和坐姿推胸测试下肢和上身的肌肉力量，以及通过火烈鸟平衡测试静态平衡能力。使用实足年龄、性别、人体测量学和身体成分，采用分层方法通过回归分析来研究体能的决定因素。为了尽量减少预测变量中共线性的预期影响，采用了一种使用随机森林分析的原始统计方法。
年龄分别预测了30米短跑、坐姿推胸、立定跳远和火烈鸟平衡测试中45.2%、43.6%、35.6%和25.6%的方差；性别分别预测了9.5%、10.7%、6.3%和2.0%的方差。人体测量学和身体成分解释的方差比例有限或为零。30米短跑、坐姿推胸、立定跳远和火烈鸟平衡测试的调整后均方根误差分别为0.61（0.31秒）、0.45（0.32米）、0.58（0.15米）和0.41（0.75对数），这使得这些模型在体能测试不可行时很有用。
我们强调了实足年龄、性别、人体测量学和身体成分在6至12岁这个较宽年龄范围内儿童体能中的各自作用。数据通过严格保守的统计方法表明实足年龄是男孩和女孩体能的主要决定因素，性别起的作用有限，从而证实并扩展了先前的文献。人体测量学的作用甚至更小，未发现身体成分有作用。在规划/实施运动发展或体育教育项目时应考虑这些发现。
