In the absence of guidance from scientific evidence, a range of lymphedema prevention and management, guidelines were developed by relevant organizations around the world. These became publicly available, promoted and endorsed, particularly to women with breast cancer. The recommendations advised avoidance of any activity that could overload or restrict the lymphatic system and need for caution when participating in specific physical activities. However, over the past 20 years evidence has accumulated which has significantly challenged the safety of these recommendations, in particular for those with cancer. There now exists consistent and compelling evidence in support of exercise following a diagnosis of cancer. Participating in exercise during and following cancer treatment improves function and quality of life, reduces treatment-related morbidity, and may improve survival. Further, exercise, including resistance exercise at moderate or high load, is considered safe for those at risk- or with lymphedema. That is, exercise has not been shown to cause or worsen cancer-related lymphedema. This article provides a historical account of the advice given to patients in the prevention and management of lymphedema and how this advice has evolved.