Abstract: | The effects of morning, rush hour commuting were examined in a quasi-experimental field study involving government-employed commuters (single and carpool drivers). Commuting stress was measured as a response to variations in how difficult it was for commuters to move from home to work. The mediation of these effects by two sources of control in the commuting situation also were assessed. Control was operationalized as control over the internal environment of the car (single versus carpool driver) and choice over routes taken to get to work. Among commuters with a high impedance route, driving to work was associated with significant increases in systolic and diastolic blood pressure and decreases in behavioral performance. The stress of commuting under high impedance conditions was reduced for single drivers relative to carpoolers. Under similar conditions of high impedance, however, having the option to select more than one route to get to work seemed to be more stressful than having only one route. The practical implications of these results are discussed. |