Introduction: Industrial workers with physically demanding work have increased risk of musculoskeletal pain. The present 12-week Goldilocks Work intervention aimed to organize work among industrial workers to comprise a ‘just right’ ergonomic balance of physical behaviors (i.e., sit, stand and active) intended to promote musculoskeletal health. The paper investigates the effectiveness of the intervention in reducing low back pain after work.         

Methods: 83 workers across 28 workteams in a biotech organization were recruited. Workteams were randomly allocated to receive the intervention or work as usual (control). Intervention workteams implemented the Goldilocks Work planning tool to organize their work tasks towards a predefined ‘just right’ ergonomic balance (i.e., composition of 60% sitting, 30% standing, 10% active work and hourly task alternation). The primary outcome was low back pain intensity. Secondary outcomes were bodily pain, fatigue, physical exertion, productivity and energy after work measured in the survey, and composition and alternations of physical behaviors measured using wearable sensors.  

Results: The intervention was delivered almost as planned, with good quality and high adherence among most workteams. However, the intervention did not change physical behaviors towards the intended ‘just right’ ergonomic balance. No significant reduction in low back pain (0.07, CI 95%: -0.68; 0.82), bodily pain (0.10, CI 95%: -0.57; 0.76), tiredness (-0.53, CI 95%: -1.24; 0.19), physical exertion (-0.18, CI 95%: -0.83; 0.48), or improvement in energy (0.39, CI 95%: -1.02; 0.23) or productivity (-0.03, CI 95%: -0.77; 0.72) were found. 

Conclusion: This Goldilocks Work intervention did not promote musculoskeletal health among industrial workers, and did not change physical behaviors as intended. Thus, more research is needed into implementation strategies to change physical behaviors during productive work towards an evidence-based ‘just right’ ergonomic balance.