Participants will be asked to complete self-administered questionnaires. At baseline, apprentice participants will complete a demographic questionnaire. At baseline, at the conclusion of primary training, and then at six and 12 months post-primary training (follow-up), participants will also complete health questionnaires (musculoskeletal symptoms and general health perceptions) as well as training content questionnaires. Similar measurement intervals have been used by other investigators to assess durability of training [33, 38]. All training groups (intervention and control) will be measured at the same intervals with the same study instruments. The questionnaires and outcome measures are described below.