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Objective Few earlier studies on cumulative exposure to high physical workload and shoulder diseases have been reported. This study aimed to investigate the association between cumulative exposure to heavy lifting and working with hands above shoulder level and diagnosed shoulder diseases across four Nordic countries.Material and Methods A meta-analysis was performed using four national register-based cohorts: the Finnish SLFF, the Norwegian Nor-Work, the Swedish SWIP and the Danish DOC*X. Exposures to heavy lifting and working with hands above shoulder level were assessed using a gender-specific European job exposure matrix (EuroJEM) for physical workload assigned to occupational codes. Participants born 1933-1985 with at least 10 years of employment were followed until first patient visit due to shoulder disease (ICD-10 codes M75), death, emigration, or end of follow-up. Cumulative exposure was calculated as years exposed from age 25-35, categorised as 0, 1-5, 6-10 and >10 years. Discrete time hazard models were used to study associations between cumulative exposures and shoulder diseases in each cohort. Meta-analyses were performed using a random effect model.Results The relative risks of shoulder diseases increased with number of years exposed to heavy lifting and working with hands above shoulders until 6-10 years of exposure. In men the risks were similar in size for 6-10 years (pooled HR 1.65[1.41;1.94] for lifting, 1.57[1.37;1.81] for hands above shoulders) and >10 years of exposure. Among women, those exposed to heavy lifting (pooled HR 1.51[1.33;1.72]) and working with hands above shoulder (HR 1.48[1,27;1.72]) for 6-10 years had the highest risks.Conclusion Reducing prolonged exposure to heavy lifting and working with hands above shoulder level has a high potential to prevent shoulder diseases in both genders.Funding The study is part of the Exposome Project for Health and Occupational Research (EPHOR) funded by the European Union’s Horizon 2020 research and innovation programme.