In a study that followed 334,161 men and women for more than 12 years, who self-reported physical activity. Just under a quarter (22.7%) of participants were categorized as inactive, due to no recreational activity and a sedentary occupation. Occupations were described as sedentary (e.g., office work), standing (e.g., hairdresser, guard), physical work (e.g., plumber, nurse), or heavy manual work (e.g.,construction worker, bricklayer).
Compared to the inactive group, the moderately inactive group had a 16-30% lower risk of dying (mortality), the moderately active group a 22-36% lower mortality and the active group a 20-41% mortality risk.
To move from the inactive to the moderately inactive group, the authors estimate that doing exercise equivalent to just a 20-minute brisk walk each day is sufficient.