Chapter 8 General discussion

8 As described in the general introduction the main goal of this dissertation was to systematically develop a tailored intervention to prevent and reduce overweight and MSD in a specific high-risk occupational group of blue collar construction workers, and to evaluate this programme in a randomised controlled trial: VIP in Construction. In order to gain more insight into the potential of body weight management as strategy for reducing MSD, we also studied the relation between body weight and musculoskeletal symptoms in worker populations. In this final chapter the main findings will be presented, discussed and interpreted in the context of recent literature. Finally, these reflections will be translated into recommendations for future research and practice. To explore if interventions reducing body weight are potentially an effective primary and secondary prevention strategy for musculoskeletal symptoms, we investigated the relation between these two health problems in chapter 2. Based on analyses in a large working population sample we found BMI to be associated with musculoskeletal symptoms, in particular symptoms of the lower extremities. Additionally, compared to employees with normal weight, obese employees were at increased risk for developing symptoms as well as having impaired recovery from symptoms. Contradictory to our hypothesis, the association was stronger for employees with low physical workload compared to those with high physical workload. In chapter 3 the systematic development of the intervention programme as well as the design of the RCT was described. The Intervention Mapping protocol was applied to systematically develop the VIP in Construction programme, targeted at blue collar workers of a large construction company. This resulted in specific programme objectives aimed at quantity and quality of energy intake and output. After selecting relevant determinants and theoretical methods of behaviour change, practical strategies were formulated. The intervention programme consisted of individual face-to-face and telephone counselling, both employing information and materials aimed to improve lifestyle behaviour. The programme was tailored to each participant's motivational readiness for change, varying in focus, number, and duration of counselling sessions. The intervention was linked to the company's periodic health screening and took place at the worksite and during working hours. Management and workers were involved in the development of the programme. Therefore, the programme matched the needs and preferences of the target group, which facilitated implementation. In chapter 4 the process evaluation of the intervention was reported. The process evaluation was conducted following the RE-AIM framework for the evaluation of …