Unit for Preventive Nutrition, Department of Biosciences and Nutrition at NOVUM, Karolinska Institutet, Huddinge, Sweden.
Am J Hum Biol. 2010 Nov-Dec;22(6):750-6. doi: 10.1002/ajhb.21076.
The purpose of this study was to determine the sex-specific physical activity (PA) intensity thresholds that best discriminate between unhealthy/healthy cardiorespiratory fitness (CRF).
Participants included 1,808 adolescents (964 girls), aged 12.5-17.5 years, from the HELENA study. We measured PA by accelerometer and calculated the time spent at light, moderate, vigorous, and moderate-to-vigorous (MVPA) intensities. CRF was assessed by the 20-m shuttle-run test. Adolescents were dichotomized (unhealthy/healthy) based on sex- and age-specific FITNESSGRAM standards. Receiver operating characteristic (ROC) analysis was used to determine thresholds that best discriminate between CRF categories.
ROC analyses revealed that the PA thresholds that best discriminate between unhealthy/healthy CRF were ≥152, ≥33, ≥13, and ≥52 min/day in light, moderate, vigorous, and MVPA, respectively. In boys, the PA thresholds associated with a healthy CRF were ≥37, ≥19, and ≥56 min/day in moderate, vigorous, and MVPA, respectively, whereas in girls were ≥152, ≥34, ≥12, and ≥51 min/day in light, moderate, vigorous, and MVPA, respectively. Spending at least 60 min/day in MVPA was also associated with a healthy CRF (odds ratios: 1.75, 1.94, and 1.57, all P < 0.05, for the whole sample, boys, and girls, respectively).
This study shows sex- and intensity-specific PA thresholds to discriminate between adolescents with a healthy CRF from those with a less favorable or unhealthy CRF level.
本研究旨在确定最佳区分不健康/健康心肺适能（CRF）的性别特异性体力活动（PA）强度阈值。
参与者包括来自 HELENA 研究的 1808 名青少年（964 名女孩），年龄在 12.5-17.5 岁之间。我们通过加速度计测量 PA，并计算出在低强度、中强度、高强度和中高强度（MVPA）强度下的时间。CRF 通过 20 米穿梭跑测试进行评估。青少年根据性别和年龄特异性 FITNESSGRAM 标准分为（不健康/健康）两类。使用接收者操作特征（ROC）分析来确定最佳区分 CRF 类别的阈值。
ROC 分析显示，最佳区分不健康/健康 CRF 的 PA 阈值分别为低强度≥152 分钟/天、中强度≥33 分钟/天、高强度≥13 分钟/天和 MVPA≥52 分钟/天。在男孩中，与健康 CRF 相关的 PA 阈值分别为中强度≥37 分钟/天、高强度≥19 分钟/天和 MVPA≥56 分钟/天，而在女孩中，分别为低强度≥152 分钟/天、中强度≥34 分钟/天、高强度≥12 分钟/天和 MVPA≥51 分钟/天。每天至少进行 60 分钟的 MVPA 也与健康 CRF 相关（整个样本、男孩和女孩的比值比分别为 1.75、1.94 和 1.57，均 P<0.05）。
本研究显示了性别和强度特异性 PA 阈值，可区分具有健康 CRF 和不太有利或不健康 CRF 水平的青少年。
