School of Health Sciences, Örebro University, Örebro, SWEDEN.
Med Sci Sports Exerc. 2018 Jul;50(7):1502-1507. doi: 10.1249/MSS.0000000000001582.
To examine the influence of reallocating time spent at different objectively measured physical activity (PA) behaviors on markers of systemic inflammation in older women with different levels of metabolic risk.
Accelerometer-based monitoring of PA was conducted in a population of community-dwelling older women (n = 111; age, 65-70 yr) for determination of daily sedentary time, time in light PA (LPA) and moderate-to-vigorous PA (MVPA). Blood samples were collected for the assessment of the systemic inflammatory markers C-reactive protein (CRP), fibrinogen, and adiponectin. Metabolic risk was assessed by standardized procedures based on definitions for the metabolic syndrome. Data were analyzed by linear regression models based on isotemporal substitution analysis.
Reallocating 30 min of sedentary time with either time in LPA (β = -0.47; P < 0.05) or MVPA (β = -0.42; P < 0.05) was related to reduced fibrinogen level, whereas no corresponding effect was evident when shifting time in LPA with time in MVPA, while holding sedentary time constant. In contrast, reallocating a 30-min period in sedentary (β = -0.70; P < 0.01) or LPA (β = -0.71; P < 0.01) with MVPA was associated with a significant reduction in CRP level, whereas no impact on CRP was observed when a period of sedentary behavior was replaced with LPA. Importantly, all significant influences on fibrinogen and CRP by displacement of different PA behaviors remained after adjustment for metabolic risk status among participants. No significant associations with adiponectin were observed.
Altogether, this work supports the existence of different intensity thresholds mediating beneficial effects of PA on important clinical markers of systemic inflammation in older women across different stages of disease prevention.
研究重新分配不同客观测量的身体活动（PA）行为时间对代谢风险不同的老年女性系统炎症标志物的影响。
对社区居住的老年女性（n=111；年龄 65-70 岁）进行基于加速度计的 PA 监测，以确定每日久坐时间、低强度 PA（LPA）和中高强度 PA（MVPA）时间。采集血液样本评估系统炎症标志物 C 反应蛋白（CRP）、纤维蛋白原和脂联素。代谢风险通过基于代谢综合征定义的标准化程序进行评估。数据分析采用基于等时替代分析的线性回归模型。
将 30 分钟久坐时间重新分配给 LPA（β=-0.47；P<0.05）或 MVPA（β=-0.42；P<0.05）与纤维蛋白原水平降低有关，而当保持久坐时间不变时，将 LPA 时间转移到 MVPA 时则没有相应的效果。相比之下，将 30 分钟久坐（β=-0.70；P<0.01）或 LPA（β=-0.71；P<0.01）时间重新分配给 MVPA 与 CRP 水平显著降低有关，而当用 LPA 代替久坐行为时，CRP 没有影响。重要的是，在调整参与者的代谢风险状态后，所有与不同 PA 行为置换有关的纤维蛋白原和 CRP 的显著影响仍然存在。与脂联素没有显著关联。
总之，这项工作支持在不同疾病预防阶段的老年女性中，不同强度阈值存在介导 PA 对系统炎症重要临床标志物有益影响的假设。
