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Introduction: Regular moderate‐to‐vigorous physical activity (MVPA) is associated with improved mental health, but the evidence for the effect of reducing sedentary behavior (SB) or increasing light PA (LPA) in older adults is lacking. Using isotemporal substitution (IS) models, the aim of this paper was to investigate the effect of substituting SB with LPA or MVPA on associations with mental health in older adults. Methods: Data from 1360 older adults (mean age 75.18 years) in four countries were utilized. PA and SB was measured using ActiGraph wGT3X‐BT + accelerometers worn for 7 days. Self‐rated mental health was measured using the Hospital and Anxiety Depression Scale (HADS). IS models estimated cross‐sectional associations when 30 minutes of one behavior was substituted with another. Models were adjusted for age, sex, marital status, and educational attainment. Results: Substituting 30 minutes of SB with LPA (β −.37; 95% CI −0.42, −0.32) or MVPA (β −.14; 95% CI −0.21, −0.07) and substituting LPA with MVPA (β −.11; 95% CI −0.18, −0.04) were associated with improvements in anxiety. However, substituting 30 minutes of SB with LPA (β.55; 95% CI 0.49, 0.62) was associated with increased depression. Conclusion: Replacing 30 minutes of SB with LPA or MVPA was associated with improved anxiety symptoms in older adults. Greater benefits were observed when shifting SB and LPA to MVPA. [ABSTRACT FROM AUTHOR]

During the South Scandinavian Early Bronze Age about 3300 years ago, thousands of burial mounds were constructed of sods from fallow ground used for grazing in Denmark and northern Germany. In some of these mounds a wet, anaerobic core developed, preventing the decomposition of organic matter. A comparison of the organic matter content in these mound cores and the plough layer in modern farmland offers an opportunity to compare the soil organic carbon (SOC) stocks in ancient and modern land use systems and to evaluate the long-term trends in carbon (C) sequestration in relation to modern farmland with varying inputs of manure and inorganic fertilizers. In the present paper we compare SOC stocks based on integrated horizon-specific densities and SOC contents in three 3300-year-old buried farmland soils, representing the land use system at that time, with results from soil surveys representing modern land use systems with low and high inputs of manure. Results show that, within the upper 0.28 m, which is the average depth of present day plough layers in Denmark, soils receiving manure from intensive pig or cattle production hold c. 60% more SOC than the ancient soils from the South Scandinavian Bronze Age. In contrast, modern arable soils mainly receiving limited inputs of manure hold a SOC stock similar to that of the ancient soils. [ABSTRACT FROM AUTHOR]