Objective <p>Considering the long waiting time during chemotherapy as an opportunity to stay active, this experiment proposes to investigate the experience of breast cancer patients performing exercise during chemotherapy infusion, focusing on mood stability and levels of enjoyment.</p> Methods <p>Adult female oncology patients (24) undergoing chemotherapy were recruited to perform 20 minutes of low-intensity pedaling on a cycle ergometer (30–40% HRR) starting 10 minutes after the beginning of the chemotherapy infusion. Physical activity levels were assessed prior to the exercise session, while mood states were measured before and after the activity. Additionally, the feeling scale and the enjoyment levels were collected after the activity.</p> Results <p>The results indicated that the exercise did not significantly alter patients’ mood, maintaining stability between pre- and post-activity assessments (<i>p</i>&gt;0.05). Additionally, high affectivity levels were observed on the feeling scale (4.33 ± 0.86), along with the elevated enjoyment levels (106.9 ± 16.1), regardless of patients’ prior physical activity levels. These findings suggest that the exercise was well-received and provided a positive experience during chemotherapy infusion.</p> Conclusion <p>The findings of this study suggest that low-intensity exercise during chemotherapy infusion in breast cancer patients is feasible and well-tolerated, providing a positive experience without adverse effects on mood. These results underscore the potential of light exercise as a complementary intervention to promote emotional well-being and enhance treatment adherence, offering new perspectives for improving quality of life during chemotherapy.</p>