Abstract

Background: In earlier studies, the health benefits of physical activity have only been related to leisure time physical activity (LTPA). High occupational physical activity (OPA) might even be harmful. The current physical activity recommendations do not separate the OPA and LTPA. We investigated the effect of LTPA and OPA on cardiovascular morbidity and mortality during long-term follow-up. We also examined how heavy work affects the benefits of leisure time exercise.

Material and methods: The study was part of the OPERA study and the baseline examinations were conducted between the years 1991 and 1993. The Follow-up of events continued until the end of the year 2020. Study subjects (n = 1044) were divided into four groups according to their LTPA (“no exercise”, “irregular”, “regular” and “heavy regular”) and into three groups according to their OPA (“no activity”, “mild” and “heavy”). The amount of exercise was self-reported and the exercise status was defined at the beginning of the study. Study subjects were followed up for their overall mortality (26 years), fatal and non-fatal CVD events (24 and 20 years) and heart failure (20 years). The survival analysis was performed using Kaplan–Meier curves and Cox-proportional hazard models.

Results: “Heavy” OPA group subjects belonging to the “irregular” (less than 1–2 times 30 min exercise per week) LTPA group experienced the lowest overall mortality compared to other LTPA groups. Also, overall mortality was increased in the “mild” (p = 0.002) and CVD mortality in the” heavy” (p = 0.005) OPA group compared to “no activity”. The incidence of heart failure was increased in the “no exercise” LTPA compared to the “heavy regular” (p = 0.015) group.

Conclusions: Study subjects who were in physically demanding occupations (heavy OPA) seemed to benefit from less LTPA than WHO currently recommends. Thus we suggest targeting different LTPA recommendations to different OPA groups.