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Current approaches to predict postoperative outcomes include scores such as the American Society of Anesthesiologists (ASA) classification and the Physiological and Operative Severity Score for the enumeration of Mortality and Morbidity (POSSUM) [7]. Ihemelandu et al. noted that the Eastern Cooperative Oncology Group (ECOG) performance status and Health‐Related Quality of Life (HRQoL) measured by Functional Assessment of Cancer Therapy (FACT‐C) questionnaire are valuable predictors of postoperative morbidity in patients undergoing major surgery [8]. ECOG status has been described as well as a useful tool in the preoperative assessment of patients undergoing pelvic exenteration [9]. Preoperative physical fitness has also been identified as an independent predictor of surgical outcome. For this reason, assessment of functional capacity before a major surgery is paramount. Cardiopulmonary exercise testing (CPET) is probably the most reliable, objective, and precise means of evaluating presurgical physical fitness and the physiologic reserve. This is a dynamic and non‐invasive assessment of the cardiorespiratory system at rest and under stress, integrating expired oxygen and carbon dioxide concentrations with the measurement of ventilatory flow, thus deriving oxygen consumption (V_O2) and carbon dioxide production (V_CO2) under conditions of varying physiologic stress imposed by a range of defined external workloads. Heart rate, oxygen saturations, blood pressure, and electrocardiogram are monitored simultaneously [10]. The most frequent mode of exercise used is cycle ergometry. CPET is the gold standard method of measuring aerobic capacity, predicting postoperative outcomes, and identifying high‐risk patients [11, 12]. Several studies and systematic reviews have demonstrated that CPET is a useful tool for preoperative risk stratification in patients undergoing cardiac and non‐cardiac surgery. Studies observe that lower V_O2 peak and aerobic threshold (AT) indicate patients at increased risk of postoperative morbidity [13]. Alternative tests are six‐minute walk tests, shuttle walking, and stair climbing.