In this review, we examine the growing body of evidence suggesting that the pericardium plays an important role in modulating cardiac function during conditions of physiological stress. Specifically, we discuss the effects of the pericardium on left ventricular filling and compliance. Furthermore, we reveal that there is increasing evidence to support the contention that the pericardium is capable of adaptation in response to volume loading. We also provide data that suggests endurance-training is a good example of a physiological stressor capable of causing pericardial remodelling. These adaptations appear particularly beneficial during exercise and may explain (in part) the common finding of stroke volume increasing during exercise to a greater extent in endurance-trained athletes. However, this adaptation may also partially explain the increased susceptibility to orthostatic intolerance in endurance athletes.