Not only a healthy diet but also exercise can improve physical functioning and many aspects of quality of life. It does not matter what kind of exercise you choose, as long as it you do it on a moderate level in order to avoid excessive strain. It is advisable to exercise at a moderate intensity and on a regular basis. Running, swimming, cycling and many other sports are safe during cancer treatment. Research strongly suggests the benefits of exercise and reports positive findings in overall fitness, muscle strength and reduction of fat. It can also help to decrease cancer-related fatigue and anxiety. Patients who want to lose weight can do so, but it is recommended to avoid strong and sudden weight loss that could burden the body additionally.