The cardiovascular benefits of exercise are well known. In contrast, the impact of lifelong endurance exercise is less well understood. Long-term high-intensity endurance exercise is associated with changes in cardiac morphology together with electrocardiographic alterations that are believed to be physiologic in nature. Recent data however has suggested a number of deleterious adaptive changes in cardiac structure, function and electrical activity, together with peripheral and cerebral vascular structure and function. This review serves to detail knowledge in relation to; (1) Cardiac structure and function in veteran endurance athletes focusing on the differentiation of physiological and pathological changes in cardiac remodelling; (2) Cardiac electrical activity and the veteran endurance athlete with attention to arrhythmias, the substrate for arrhythmia generation and the clinical significance of such arrhythmias; (3) Peripheral and cerebral vascular structure and function in ageing and endurance-trained individuals; and (4) directions for future research.