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Updated: Jan 26, 2026

Visualization of Intensity Levels to Reduce the Gap Between Self-Reported and Directly Measured Physical Activity
Published on: March 7, 2019
Associations of physical activity and sedentary behaviors with mortality: An observational analysis and Mendelian
Menglin Han1, Yudun Qu2, Muhui Zeng3
1Department of Rehabilitation, The First Affiliated Hospital of Jinan University, Guangzhou, Guangdong, China.
Background:
To investigate the associations of physical activity (PA) and sedentary behavior (SB) with the risk of mortality using observational and Mendelian randomization (MR) designs.
Methods:
In a prospective cohort study based on UK Biobank, data on PA and SB were collected and categorized as three mutually exclusive groups. Multivariable-adjusted Cox models and two-sample MR analysis were performed.
Results:
Compared with low total PA (TPA), intermediate and high TPA were associated with a decreased risk of all-cause and cardiovascular disease (CVD) mortality. Compared with low levels, high total sitting time and television viewing time were associated with increased risk of all-cause and CVD mortality. The two-sample MR analysis indicated no causal relationship between genetic predispositions to PA/SB and mortality.
Conclusions:
Although PA was associated with a lower risk, prolonged sitting time was associated with an increased risk of all-cause and CVD mortality, two-sample MR did not support a causal effect.
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