How does physical demand affect cognitive performance? Interference between outdoor running and narrative memory

Dual-tasking situations are common in military, firefighting, search and rescue, and other high risk operations. Cognitive and physical demands can occur at the same time, but little is known about the specific demands of real world tasks or how they might interfere with one another. It is well known that attempting simultaneous tasks will divide and divert attention, but to what extent? In this experiment, a narrative memory task was paired with an outdoor running task, and as expected, memory task performance declined when participants were asked to run at the same time. It is suggested that more cognitively demanding physical tasks be used within this dual-task paradigm for a better understanding of the human cognitive resource structure, i.e., how and why certain tasks interfere.