Aims: The paper presents a recent Danish programme using exercise to alter the behaviour and body image of drug addicts. Methods: 38 participants (23 male and 15 female) took part in groups three times per week for a minimum of two to a maximum of six months. Self-reported data combined with the European Addiction Severity Index (EuropASI) collected at initial admission and in follow-up interviews included information on drug use, body image, self-confidence and motivation to change behaviour. Results: The completion rate of the participants during the training period was on average 52%, which is considered as a success in treatments with drug abusers, usually characterized by a low compliance and commitment. The results of the participants who completed the programme (n = 20) showed an increased oxygen uptake of an average of 10%, improved self-reported quality of life and a higher energy level for the majority of the participants. The addicts obtained a better body image, became more sensitive to physical pain and disorders and reduced their drug intake during the training period. The long-term effect showed that five of the 20 abusers interviewed reported that they still had not taken drugs, 10 had downgraded their intake, four experienced no change at all and one died through an overdose. Conclusions: The results show that physical exercise can provide important support in the treatment of drug abuse and that the main problem is maintaining change in behaviour and peer group influence to ensure long-term change.