The purpose of this study was to examine the 4-year follow-up effects of the "10 000 steps Ghent" project, which had shown increases in pedometer steps after the first year of implementation (2005-06). All adults who had participated in 2005-06 (n = 866) were recontacted in 2009 and invited to complete the International Physical Activity Questionnaire and a 7-day pedometer log. Long-term effects were analysed using repeated measures analysis of variance tests (time x community, n = 420). In subgroup analyses, age, gender, educational level, employment status, health and risk profile were also included. Results showed that daily step counts increased slightly from 2005 to 2009 in the intervention community (Ghent) and decreased in the comparison community (Aalst) (time x community: P = 0.008). Subgroup analyses showed a positive interaction effect for higher educated (P = 0.026) and healthy (P = 0.005) participants and a negative interaction for those with a poor to moderate health (P = 0.026). For self-reported physical activity, a positive interaction effect was found in those who had already reached 10 000 steps in 2005 (P = 0.037). To conclude, the positive effects seen after 1 year were not maintained after 4 years. However, a decrease from baseline to follow-up, which was seen in the comparison community, was prevented in all Ghent participants, except those with a poor to moderate health.