The aim of this study was to analyse muscle activity and subjectively perceived exertion [rating of perceived exertion (RPE)] during whole-body vibration (WBV) in breast cancer survivors. Twenty breast cancer survivors and 20 healthy controls performed isometric squats on a vibration platform. RPE and muscle activity (surface electromyography) of the rectus femoris, vastus medialis, biceps femoris, tibialis anterior and gastrocnemius were recorded under the following conditions: nonvibration (0 Hz) and vibration (20-30-40-50 Hz) conditions. No significant differences were found between groups with regard to muscle activity (P=0.471) and RPE (P=0.629). Only for vastus medialis was muscle activity higher at 20 and 30 Hz compared with 40 and 50 Hz (P<0.05). RPE increased with increasing vibration frequency; however, no difference was found between 20 and 30 Hz (P=0.088). WBV at 20 and 30 Hz revealed lower subjectively perceived exertion and the highest muscle activity and therefore provide the optimal modalities for WBV in breast cancer survivors.