PURPOSE/OBJECTIVES: To test effects of gain-framed versus loss-framed mailed brochures on increasing physical activity (PA) among colorectal cancer (CRC) survivors. . DESIGN: Randomized trial with repeated measures at baseline, 1 month, and 12 months postintervention. . SETTING: Mail recruitment from tumor registries. . SAMPLE: 148 inactive CRC survivors who had completed primary therapy. . METHODS: PA and constructs from the Theory of Planned Behavior (TPB) were assessed at baseline, 1 month, and 12 months. Participants were randomized to receive pamphlets describing PA benefits (gain framed) or disadvantages of not being physically active (loss framed). Baseline characteristics were compared using descriptive statistics. Repeated measures linear models were used to test PA changes. . MAIN RESEARCH VARIABLES: Minutes of PA and TPB constructs. . FINDINGS: Significant PA increases were observed in both study arms. Results did not differ by message frame. At one month, about 25% of previously inactive participants increased activity to national recommendations. Those who increased PA compared to those who did not had higher baseline scores on subjective norms, perceived behavioral control, and PA intentions. . CONCLUSIONS: Independent of message framing, mailed brochures are highly effective in producing within-subject short- and long-term increases in PA. . IMPLICATIONS FOR NURSING: CRC survivors may increase short- and long-term levels of PA by receiving inexpensive print brochures.