## 5 Limitations and Future Research Agenda  
This research, carried out in a real industrial environment, analyzes work patterns and their implications for the health of operators carrying out repetitive manual tasks in a particular sector of work, bringing some limitations. In this specific case study, most operators work during the daytime, without shift work, and their seniority in the company is less than 5 years. This became a limitation of this study, as it was not possible to carry out correlation studies of these variables with the perception of musculoskeletal symptoms reported by the workers. However, with the intention of industrial growth and possible expansion of shift work, it is necessary to investigate the implications of work schedules and shift work on personal life and health, considering factors such as age, gender, and children [44; 45]. Similarly, the elevated BMI of the operators may also be related to their work hours, shift work, and seniority in the company, as studies indicate that more precarious jobs in terms of work schedules and fixed-term or permanent employment contracts lead to higher health risks, notably, a higher BMI and increased stress levels [46; 47]. With the results obtained through this questionnaire, it was not possible to establish positive or negative correlations between musculoskeletal symptoms and physical exercise or sleep habits, and more detailed studies need to be carried out. Furthermore, specific analysis and evaluation of sleep habits and physical exercise practices on the health of operators must be performed, especially regarding anthropometric variations, such as BMI, and the possible consequences on the prevalence of musculoskeletal injuries. For example, it has been reported that working night shifts is associated with fewer hours of sleep and a higher BMI [34]. Moreover, the results obtained can, in the first instance, be used and applied directly in the polishing sector, i.e., the site under study. At this stage, easy-to-implement measures can be taken and small changes made to improve the working conditions, well-being, and health of the operators, as well as optimizing productivity. Furthermore, in the second instance, these data can and should be distributed to the occupational health and safety department to carry out more detailed monitoring of the measures taken and, mostly, when implementing measures that require legislative, regulatory, or financial approval. That said, to improve the accuracy of the results, anthropometric measurements will be taken in the workplace using various measuring materials, such as a stationary and/or dynamic anthropometer and a height and weight measuring station [34], thus enabling the BMI to be calculated more accurately and obtain workers' posture measurements. Also, as future research, we intend to carry out correlation analyses between these variables to define some of the possible causes of musculoskeletal injury symptoms and propose measures to improve working conditions and increase the well-being and health of operators. To perform that, it is important to incorporate and support healthy aging practices by implementing Older Worker-oriented Human Resource Practices (OW-HRPs) to reduce ageism, work-life conflict, and psychological stress [48], including workplace physical activity interventions to foster health [49] and promoting good work environments, social support, and knowledge development, including intrinsic motivation for sustainable working life [50]. On the other hand, a more detailed ergonomic assessment will be necessary to prove and/or determine the reasons for the high prevalence of musculoskeletal symptoms more precisely. For the assessment of physical ergonomics and to evaluate the sequences of actions and postures during work tasks, several ergonomic risk assessment methods can be used, such as the RULA (Rapid Upper Limb Assessment), OCRA (Occupational Repetitive Action), REBA (Rapid Entire Body Assessment, and OWAS (Ovako Working Posture Analysis System) [3].