The physical inactivity seen all around the world does not only pose a risk for the individual but is also one of the strongest modifiable risk factors for morbidity and mortality, including cancer. Physical exercise has been suggested to reduce cancer recurrence and improve health-related quality of life and survival rates among cancer patients. Despite these well-known benefits the physical activity participation rates among cancer patients are reported to be too low. Several barriers hinder the participation in physical activity such as therapy-related side effects, like fatigue and various kinds of pain, but also psychological factors, like kinesiophobia which is prevalent among cancer patients who are concerned about fall or injury. Furthermore, economic, and environmental factors, like poor weather, the lack of disabled-friendly spaces or the limited availability of cancer-specific services are reported to hinder physical activity engagement. Extended Reality (XR) could fill that gap and provide a safer and more accessible solution to improve physical activity in cancer patients. Integrating XR technology into cancer treatment could be a further stride towards a healthier future.