Sitting is the new smoking. – Health catchphrase, c.2009

Sich krank essen, trinken, sitzen: to become sick by eating, drinking, sitting too much. – A Complete Practical Grammar of the German Language (c.1805–1828) by Charl

After they had dined, Mrs. Teachum told them she thought it proper that they should use some exercise in the cooler part of the day, lest, by sitting too much, they should injure their health. – Sarah Fielding (1710–1768), “The Governess, or The Little Female Academy,”

Desidiousness. Lat. sitting too much; slothfulness, idleness, carelessness. – A New Dictionary of the English Language by Charles Richardson, 1836