The effect of exercise on neck-shoulder pain was studied in 103 women with work-related trapezius myalgia randomized into three exercise groups and a control group. One group trained strength, the second muscular endurance and the third co-ordination. The exercise groups met three times weekly for 10 weeks. Pain assessment was made on three visual analogue scales, indicating pain at present, pain in general and pain at worst. Pain thresholds were measured in the trapezius muscle with a pressure algometer. A pain drawing was completed. The rated pain decreased significantly (P<0.05) on the VAS describing pain at worst in the strength and endurance groups. Pressure sensitivity decreased significantly (P<0.05) in four triggerpoints in the exercise groups. No changes were seen in the extent of painful body area in any group. Comparison of exercisers (n=82) and controls (n=21) showed significantly larger pain reductions on VAS pain at present and VAS pain at worst among exercisers. All three exercise programs showed similar decreases of pain which indicates that the type of exercise is of less importance to achieve pain reduction.