Abstract Background and objective Given the failure of handler training programs that focus solely on the “straight back, bent knees” safe lifting technique, a new approach called “Integrated Prevention Strategy for Manual Handling” (IPSMH) was proposed in 2011. Part of its originality lies in the use of nine movement principles that make it possible to understand and analyze the many techniques handlers use naturally in their jobs. The main objective of the present study was to observe a group of OHS practitioners trained in the IPSMH and evaluate to what extent they appropriate this approach and teach it during interventions in actual workplaces. Methodology The study was made up of four complementary, sequential parts. First, an online questionnaire was developed in order to survey the OHS intervention practices of a population (n=104) of practitioners in Québec (Part 1). Next, 28 practitioners were trained in the IPSMH. After the training, several predictive transfer indicators were evaluated by means of a questionnaire (Part 2). A mixed qualitative methodology involving various data-gathering tools was then used to evaluate the subjects’ appropriation and transfer of IPSMH during actual workplace interventions related to manual material handling (n=19) over a two-year period (Part 3). Indicators and determining factors were applied and each subject’s level of transfer was ranked exemplary, satisfactory or poor. In addition, the subjects’ application of the movement principles as part of their interventions was analyzed in depth. On the basis of the results obtained, recommendations were formulated as to ways of improving the IPSMH and of training trainers in its correct application (Part 4). Principal results Part 1: The survey revealed that the work of OHS practitioners in Québec consists largely in the preparation and delivery of information and training sessions. The predominant pedagogical approach is the transmission of knowledge; rarely is the learners’ active, contextualized involvement solicited. These practitioners may be considered experts in OHS training, with more than 10 years of experience on average. However, since their job is to offer training on many different topics, they are actually generalists rather than experts in any particular field such as manual material handling. Knowing this, the researchers were able to adapt the IPSMH training to the reality of OHS practitioners. Part 2: The predictive indicators evaluated after the training suggest that the training has a high potential for encouraging the transfer of knowledge to the workplace. The subjects perceived the content as useful and said they felt they mastered it well, were able to apply the skills they had learned, and intended to teach them to workers during future interventions. Their confidence in their personal ability to apply the IPSMH—a strong predictor of transfer—was very high, on average. These results led the research team to check the actual extent of the subjects’ transfer of the training content to the workplace. Part 3: Of the 28 subjects trained, the researchers were able to observe 16 conducting interventions, some of them more than once, for a total of 19 cases observed. The interventions took place in various workplaces and involved manual handling tasks that were highly varied in nature and complexity. The clients benefiting from the interventions were either production workers (n=13) (the IPSMH target group), company employees responsible for training (n=3) (e.g., supervisors) or other (n=3) (e.g., rehabilitation experts). For 10 of the 13 sessions provided to production workers, the indicators were evaluated in greater detail and showed excellent appropriation by the subjects in several respects. However, two cases showed a poor level of appropriation. The interventions offered by the subjects diverged from the IPSMH mainly in that they were shorter in duration, they rarely proposed any improvements to working conditions, and there were certain differences in the training structure put in place to stimulate learning. The subjects cited factors related to their own job conditions (e.g., excessive work load) or to the client company’s situation (budget constraints, etc.) that force them to adapt the IPSMH to fit the context. The research team was able to identify a number of other factors, some linked to individual subjects, some to the nature of the handling task, and some to the person receiving the intervention (also mentioned by a few of the subjects). The subjects applied the movement principles as they were taught to do, although some principles tended to be emphasized while others were glossed over (a fairly strong “postural bias” was noted). Finally, rather than incorporating the recommendations for improvements to the IPSMH approach and training into the study results, the authors have placed them throughout the discussion section in insets (Part 4). Discussion The results suggest an “evolving” form of appropriation. On the one hand, the subjects showed a strong ability to appropriate and transfer the training content: their use of the movement principles and other concepts was very much in line with the IPSMH, although a few lapses were noted. They made obvious efforts to contextualize the training content, to choose suitable pedagogical tools and to apply strategies for eliciting exchanges among participants and creating a good dynamic. On the other hand, they are faced with a contradiction between two teaching paradigms: one emphasizing the transmission of theory, the other emphasizing the learners’ active involvement in constructing their own knowledge. Practitioners must therefore make difficult transitions—along with the corresponding compromises: a. from a role as expert trainer to a new role as mediator of learning, which touches on their professional identity; b. from strict control over content and delivery, to a certain tolerance for uncertainty while taking into account the normative requirements of training; c. from knowledge-based content to content focusing on motor skills related to job requirements and training topics; d. between the needs of the client company and those of the client employee in terms of the training mandate and objectives. These transitions can be destabilizing and can hinder the application of the IPSMH if the practitioner does not feel guided and supported. Key points Despite the complexity of the IPSMH and the obvious paradigm rupture it involves, most of the OHS practitioners trained in the approach were able to appropriate it and teach it in their day-to-day workplace interventions. The IPSMH is appreciated by all stakeholders. There are still divergences between certain IPSMH concepts and conventional practice, some of which are attributable to obstacles that the practitioners try to work around. Such adjustments are unavoidable, for the time being. OHS practitioners trained in the IPSMH are transitioning from their old training practices to new pedagogical requirements under the IPSMH; the resulting contradictions can be destabilizing and even discouraging if the practitioner is not well supported.