The prevalence of pain in the shoulder, arm and hand is high among slaughterhouse workers, allegedly due to the substantial load of these body regions during work. Work disability is a common consequence of these pains. Lowering the physical exposure through ergonomic intervention may be a strategy to reduce the workload. An alternative strategy could be to increase the physical capacity through strength training of the shoulder-, arm- and hand-muscles. This study investigates the effect of two contrasting interventions, i.e. load reduction (ergonomic intervention) versus training of physical capacity (strength training) on pain and work disability in slaughterhouse workers.

The main hypothesis is that strength training intervention for 10 weeks compared with ergonomic intervention results in reduced pain of the shoulder, arm and hand.

Inclusion Criteria:

• Slaughterhouse worker
• the pain should have lasted at least 3 months
• pain intensity during the last three months of >= 3 (scale 0-10) in the shoulder, elbow or hand
• the pain should be frequent (at least 3 days per week)

Exclusion Criteria:

• life threatening disease
• pregnancy