Department of Community Medicine, University of Tromsø, and Department of Clinical Therapeutic Services, University Hospital of Northern Norway, Tromsø, Norway.
Med Sci Sports Exerc. 2011 Jul;43(7):1229-34. doi: 10.1249/MSS.0b013e3182084562.
Physical activity plays an important role in the prevention of many serious diseases. To develop targeted strategies that encourage physical activity, knowledge of stability of physical activity levels over time is essential. The aim of this study was to examine tracking of leisure time physical activity in adults in Northern Norway during three decades.
We followed 5432 women and men who attended the Tromsø Study in 1979-1980, as well as repeated examinations after 7 and 28 yr. Baseline age was 20-54 yr (mean age=35.8 yr). Physical activity was assessed by self-administered questionnaires. Tracking of physical activity, defined as maintenance of relative rank of physical activity level, was estimated by Spearman correlation coefficient and by weighted κ statistics. Tracking in terms of predictability of later values from earlier measurements was analyzed by generalized estimating equations.
A higher-than-expected proportion of subjects maintained their physical activity level from examination 1 to 2 (58%) and 3 (53%). κ statistics showed agreement of 0.41 and 0.29, respectively. Belonging to a specific physical activity level at baseline increased the odds of belonging to the same category at later examinations (sedentary odds ratio (OR)=3.9 (95% confidence interval (CI)=3.5-4.4), moderately active OR=2.2 (95% CI=2.0-2.4), active OR=2.9 (95% CI=2.6-3.3), and highly active OR=14.0 (95% CI=8.7-22.5)). Being physically active in young adulthood increased the odds of being physically active later in life (moderately active OR=3.4 (95% CI=3.0-3.9), active OR=5.4 (95% CI=4.6-6.4), and highly active OR=13.0 (95% CI=7.4-22.8)).
This study showed tracking of leisure time physical activity during 28 yr in a cohort of adults.
身体活动在预防许多严重疾病方面发挥着重要作用。为了制定鼓励身体活动的有针对性的策略，了解身体活动水平随时间的稳定性至关重要。本研究旨在检验挪威北部成年人在三十年期间的休闲时间身体活动的追踪情况。
我们跟踪了 1979-1980 年参加特罗姆瑟研究的 5432 名女性和男性，以及 7 年和 28 年后的重复检查。基线年龄为 20-54 岁（平均年龄=35.8 岁）。身体活动通过自我管理的问卷进行评估。通过 Spearman 相关系数和加权κ统计来评估身体活动的追踪情况，定义为身体活动水平的相对等级保持。通过广义估计方程分析从早期测量值预测后期值的可预测性。
从第一次检查到第二次（58%）和第三次（53%），高于预期比例的受试者保持了他们的身体活动水平。κ统计数据分别显示了 0.41 和 0.29 的一致性。在基线时属于特定的身体活动水平会增加以后检查时属于同一类别的可能性（久坐不动的比值比（OR）=3.9（95%置信区间（CI）=3.5-4.4），适度活跃的 OR=2.2（95% CI=2.0-2.4），活跃的 OR=2.9（95% CI=2.6-3.3），高度活跃的 OR=14.0（95% CI=8.7-22.5））。在年轻成年人时期进行身体活动会增加以后进行身体活动的可能性（适度活跃的 OR=3.4（95% CI=3.0-3.9），活跃的 OR=5.4（95% CI=4.6-6.4），高度活跃的 OR=13.0（95% CI=7.4-22.8））。
本研究表明，在一个成年人队列中，在 28 年内休闲时间身体活动具有可追踪性。
