Purpose : The primary aim was to determine the effect of a physical activity (PA) program with education sessions on walking capacity and fatigue in people with cancer. The secondary objective was to assess the factors that moderated the program’s effect on walking capacity and fatigue among sociodemographic, physical capacity and symptom-related factors. Satisfaction with the program was also evaluated. Method : A retrospective, observational study of data from a 12-week program of twice-weekly group PA sessions combined with education sessions was conducted. The 6-min walk test (6MWT), the Multidimensional Fatigue Inventory (MFI-20) and program satisfaction were assessed. Paired t-tests were applied to assess changes in 6MWT and MFI-20. Multiple linear regressions were applied to determine the influence of age, gender, initial walking capacity and fatigue on the effects of the program. Results : Among the 264 participants (age 57.36 ± 12.43 years; 189 women; 134 with breast cancer), 125 (47%) completed the program. Walking capacity (+ 41.63 ± 91.00 m) and fatigue (-2.01 ± 3.77) were improved after the program (p < 0.001). Age and gender did not influence the program’s effect; however, lower initial walking capacity and higher fatigue scores were associated with larger improvements after the program. Satisfaction with the program was high among participants who completed it. Conclusions : Walking capacity and fatigue improved significantly after the PA program, but the drop-out rate was high. The program could be individualized based on an individual's initial walking capacity or fatigue score to enhance its effectiveness.