Background: Exercise promotes numerous advantages in both health and disease, and is increasingly being acknowledged to improve overall survival in cancer patients. Preclinical studies indicate a direct effect on tumour behaviour, but human data on the effect of exercise on tumour progression are lacking. Aims: To capture preliminary clinical data regarding the impact of a prescribed, supervised exercise programme on cancer disease progression. Methods: Retrospective cohort study of 137 matched pairs of patients. All patients referred to LIFT Cancer Care Services (LIFT) supervised exercise programme between 2018 and 2019 were matched with non‐LIFT patients from the oncology practice database. Disease progression via staging computed tomography scans ± tumour markers was compared for each match. Secondary outcomes were changes in neutrophil‐to‐lymphocyte ratio (NLR) and death. Results were analysed by logistical regression and adjusted for potential confounders. Results: Patients from the LIFT group had a 66% (OR = 0.34, 95% CI 0.19 to 0.61) decreased odds of disease progression and 76% (OR = 0.24, 95% CI 0.12‐0.47) decreased odds of death compared with the non‐LIFT group. No effect on the number of LIFT sessions on disease progression was demonstrated. The LIFT group had a mean final NLR reading 3.48 (−5.89 to −1.09) lower than the non‐LIFT group. Conclusion: Supervised exercise programmes have the potential to significantly improve outcomes in cancer patients due to an effect on tumour progression. [ABSTRACT FROM AUTHOR]