Off-the-shelf wireless sensing devices open a wide range of perspectives for tetherless biomedical monitoring. Yet most applications considered to date imply either indoor realtime data streaming or ambulatory data recording. Disruption-tolerant networking is a means to cope with challenging situations where continuous end-to-end connectivity between communicating devices cannot be guaranteed. In this paper we investigate the possibility of using this approach to remotely monitor the cardiac activity of runners during a marathon race, using off-the shelf sensing devices and a limited number of base stations deployed along the marathon route. Preliminary experiments show that such a scenario is indeed viable, although special attention must be paid to balancing the requirements of ECG monitoring with the constraints of episodic, low-rate transmissions.