Recess time (RT) is a main component of school-based activities, and could contribute up to 40% of the physical activity (PA) recommended in the health guidelines. The main goal was to analyze the association between accelerometer-measured PA and sedentary time during RT with cardiorespiratory fitness (CRF). A total of 146 children and adolescents, aged 8–19 years, were recruited from six schools. PA levels were measured with GT3X accelerometers over 7 days. CRF was measured using a portable breath-by-breath gas analyzer. A general linear model (GML) was conducted to analyze the association between PA intensities and CRF during RT. Additionally, a logistic binary regression was used to evaluate the risk of unhealthy CRF among different categories of PA and sedentary time. Participants classified as healthy showed higher PA levels during RT than those classed as unhealthy. GML analysis showed that sedentary time during RT was significantly associated with VO_2Peak. Finally, individuals who were sedentary for more than 15 min during RT presented 97.7% lower odds of having unhealthy CRF (adjusted Odds Ratio = 0.023, 95% CI −0.002 to 0.263). Our data suggest an association between recess sedentary time and unhealthy CRF. Thus, school-aged children and adolescents must be empowered to perform PA during RT to prevent the deleterious effects of sedentary time on CRF.

中文翻译：

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学校课间休息期间的久坐和体力活动与摄氧量峰值相关。


课间休息时间 (RT) 是校内活动的主要组成部分，可占健康指南中建议的体力活动 (PA) 的 40%。主要目标是分析加速计测量的 PA 和 RT 期间静坐时间与心肺健康 (CRF) 之间的关联。来自 6 所学校的 146 名 8-19 岁儿童和青少年被招募。使用 GT3X 加速计测量 7 天的 PA 水平。 CRF 使用便携式呼吸气体分析仪进行测量。采用一般线性模型 (GML) 来分析 RT 期间 PA 强度与 CRF 之间的关联。此外，还使用逻辑二元回归来评估不同类别的 PA 和久坐时间之间不健康 CRF 的风险。被分类为健康的参与者在放疗期间表现出比被分类为不健康的参与者更高的 PA 水平。 GML 分析表明，RT 期间的静坐时间与 VO _2Peak显着相关。最后，在 RT 期间久坐超过 15 分钟的个体出现不健康 CRF 的几率降低 97.7%（调整后的优势比 = 0.023，95% CI -0.002 至 0.263）。我们的数据表明课间休息时间与不健康的 CRF 之间存在关联。因此，学龄儿童和青少年必须有权在 RT 期间进行 PA，以防止久坐时间对 CRF 产生有害影响。