The evaluation of cardiac function across the health spectrum under diverse conditions of physiological stress: introduction.

In this paper we introduce 3 papers resulting from a symposium evaluating cardiac function across the health spectrum under varied conditions of physiological stress. Esch et al. (Appl. Physiol. Nutr. Metab. 32: this issue) evaluate the potential role the pericardium plays on diastolic filling in endurance-trained athletes. These authors reveal how pericardial remodelling may explain (in part) why endurance athletes can achieve superior stroke volumes during exercise while also being increasingly susceptible to orthostatic intolerance. Warburton et al. (Appl. Physiol. Nutr. Metab. 32: this issue) review the central and peripheral mechanisms responsible for the exercise intolerance of chronic heart failure. They also reveal the important therapeutic effects of exercise rehabilitation for the treatment of heart failure. Scott et al. (Appl. Physiol. Nutr. Metab. 32: this issue) highlight the cardiovascular consequences of the gravitational stress placed upon pilots and the countermeasures commonly used. Collectively, these articles highlight the importance and difficulty of assessing cardiac function under varied conditions of physiological stress.