Prolonged Sitting Harmful Regardless of Exercise无论锻炼与否，久坐有害健康

A systematic review and meta-analysis revealed that prolonged sedentary time was independently associated with deleterious health outcomes regardless of physical activity. Meta-analyses were performed on outcomes for cardiovascular diseases and diabetes (14 studies), cancer (14 studies), and all-cause mortality (13 studies). Prospective cohort designs were used in all but 3 studies; sedentary times were quantified using self-report in all but 1 study. Significant hazard ratio (HR) associations were found with all-cause mortality, mortality of cardiovascular diseases and cancer, as well as incidences of cardiovascular diseases, cancer, and type 2 diabetes. HRs associated with sedentary time and outcomes were generally more pronounced at lower levels of physical activity than at higher levels. Sedentary behavior was defined as sitting, watching television, or lying down. Source: http://annals.org/一项系统综述和荟萃分析表明，久坐不动的时间与不利健康结果有关，无论锻炼与否。对心血管病和糖尿病（14项研究），癌症（14项），以及全因死亡率（13项研究）进行了荟萃分析。除了3项研究以外所有研究均采用前瞻性设计；久坐不动的时间用自我报告定量，只有1项研究例外。风险比率（HR）与全因死亡率，心血管病和癌症的死亡率，以及心血管病，癌症和2型糖尿病发生率等显著相关。体育锻炼水平较低者与久坐时间相关的HR比体育锻炼水平较高者普遍更为显著。久坐不动的行为被定义为坐着，看电视，或躺着。来源：http://annals.org/