The purpose of this single participant case-study was to assess the effectiveness of using a non-invasive ECG system for the determination of the cardiovascular responses to closed-wheel motor racing and to offer some insights into the practicalities of working in the field with extreme sports participants. A professional racing driver participated in two driving trials and a laboratory based assessment of V̇O2max. During the driving trials HR telemetry was recorded every 15 s using the Actiheart system. Linear regression interpolation techniques were applied to the laboratory data for the estimation of the metabolic cost of driving from the collected HR data. During the practice session, HR was closely related to driving pace (p < 0.05). The metabolic demand for the 45 min session was 44.5 ± 16.6 kJ·min−1. In the competition trial the mean HR response was 182.1 ± 6.9 b·min−1, with an energy expenditure of 59.6 ± 9.5 kJ·min−1. The results from this study indicate that there is a profound metabolic strain associated with motor racing and that the Actiheart system provides a non-invasive means of determining the physical demands of automobile motor racing. However, metabolic demand may be overestimated in the presence of other influences on heart rate during competition.