Department of Exercise Sciences, Brigham Young University, Provo, Utah, USA.
Obesity (Silver Spring). 2011 Oct;19(10):1950-6. doi: 10.1038/oby.2011.184. Epub 2011 Jun 30.
We assessed the roles of energy intake and physical activity in the relationships among television (TV) viewing, body composition, and obesity using high-quality measurement methods. Adult women (n = 300) reported TV viewing behavior, which was categorized into infrequent (≤ 1 h/day), moderate (2 h/day), and frequent (≥ 3 h/day) viewing. Body fat percentage (BF%) was assessed using plethysmography (Bod Pod) and BMI was calculated from height and body weight. Energy intake and physical activity, including time spent in sedentary, moderate, and vigorous physical activity (PA), were objectively measured using 7-day weighed food records and 7-day accelerometry, respectively. The mean BF% of frequent TV viewers (34.6 ± 6.9%) was significantly greater (F = 3.9, P = 0.0218) than those of moderate (31.5 ± 6.7%) and infrequent viewers (30.8 ± 7.0%); however, BMI did not differ across the TV viewing groups (F = 0.8, P = 0.4172). Controlling statistically for differences in age, education, time in sedentary activity, time in moderate activity, and energy intake, considered individually, had no influence on the relationships between TV viewing and BF%, nor TV and BMI. Moreover, the relationship between TV and BF% remained significant after adjusting for differences in BMI (F = 3.6, P = 0.0276). However, adjusting for total PA reduced the relationship between TV and BF% to nonsignificance (F = 2.5, P = 0.0810), as did time spent in vigorous PA (F = 2.2, P = 0.1307). These data suggest a strong relationship between TV viewing and BF%. This association appears to be due, in part, to differences in total PA, particularly vigorous PA, but not time spent in sedentary activity, moderate activity, or energy intake.
我们使用高质量的测量方法评估了能量摄入和体力活动在电视（TV）观看、身体成分和肥胖之间关系中的作用。成年女性（n = 300）报告了 TV 观看行为，该行为分为不频繁（≤ 1 小时/天）、中度（2 小时/天）和频繁（≥ 3 小时/天）观看。体脂百分比（BF%）使用体积描记法（Bod Pod）进行评估，BMI 则由身高和体重计算得出。能量摄入和体力活动，包括久坐、中度和剧烈体力活动（PA）的时间，分别使用 7 天称重食物记录和 7 天加速度计进行客观测量。频繁观看 TV 的人的平均 BF%（34.6 ± 6.9%）明显高于中度（31.5 ± 6.7%）和不频繁观看者（30.8 ± 7.0%）（F = 3.9，P = 0.0218）；然而，BMI 在不同的 TV 观看组之间没有差异（F = 0.8，P = 0.4172）。单独考虑控制年龄、教育程度、久坐活动时间、中度活动时间和能量摄入的差异，对 TV 观看与 BF%之间的关系以及 TV 与 BMI 之间的关系没有影响。此外，在调整 BMI 差异后，TV 与 BF%之间的关系仍然显著（F = 3.6，P = 0.0276）。然而，调整总 PA 后，TV 与 BF%之间的关系变得不显著（F = 2.5，P = 0.0810），剧烈 PA 时间也是如此（F = 2.2，P = 0.1307）。这些数据表明，TV 观看与 BF%之间存在很强的关系。这种关联似乎部分归因于总 PA，特别是剧烈 PA 的差异，但与久坐活动、中度活动或能量摄入无关。
