Every second is valuable in formula-one (F1) racing, so it requires real-time monitoring of performance. While the mechanical aspects of the race can be monitored, there is currently no appropriate method for monitoring brain controls of human functions during racing. We have investigated the role of cardiac vagal tone (CVT) in F1 racing because of the importance of central parasympathetic restraint during both mental and physical challenges. We asked a current professional racing F1 driver to volunteer as a subject to be monitored during practice in a simulator equipped with all aspects of F1 racing except the moments of inertia forces (G-force). He was wearing the full racing suite with helmet, but we added the Neurozoid wireless electrocardiogram (ECG) sensors placed in a conformation of modified Einthoven Lead II position (Neurozoid, Extreme Biometrics, Tunbridge Wells, Sussex, UK). The Neurozoid fed the ECG to a cloud-based processor via a wireless mobile device for the measurement of CVT in real-time using the NeuroScope method previously described in details (Julu et al., 2003). The CVT is measured in clinically validated, atropine-derived units of the Linear Vagal Scale (LVS, Julu 1992) and data is sent back from the cloud-based processor to the telemetry desk of the race Engineer in real-time. The driver carried out two drives of ten laps each separated by 30 minutes of rest period in a simulated Yas Marina race circuit in Abu Dhabi. This race tract is notorious for its long high-speed straights ending with sharp bends requiring intense and heavy braking. The pre-race CVT remained above 30 LVS units at the start of both drives, but was quickly withdrawn to below 5 LVS units when the driver pulled from the pit to the race track (Fig.1). The normal range of resting supine CVT in sedentary non-athletes is 5-10 LVS units (Mckechnie et al., 2002). The CVT remained below 5 units during racing except when driving on the long high-speed straights when it recovered briefly to levels above 15 LVS units only to be quickly withdrawn again to levels below 10 LVS units during the sharp bends at the end of the straights (Fig.1). The CVT responses were consistent during the two drives (Fig.1). Real-time changes in CVT can be monitored continuously during F1 racing and it consistently matched the task being performed by our F1 volunteer driver, where intense engagements caused vagal withdrawals to the extents that reflected the speed and intensity of the tasks being performed. The pre-race CVT level in the driver was nearly threefold that in sedentary people. We propose that the extent of CVT withdrawal can be used as a physiological measure of engagement and or perceived difficulty of a task in F1 racing. This can be interpreted as a measure of the perceived stress while performing a particular task.