A new study shows that people using a stationary bike to exercise pedal faster when they're also working on a mental task. The University of Florida researchers had actually expected that the multitasking would hinder both activities.
From Scientific American:
Turns out, cyclists rode 25 percent faster when they were distracted by some mental gymnastics—but only when the tasks were relatively easy. When confronted with tough brainteasers, their cycling speeds were about the same as when they had nothing in particular to think about. And in case you’re wondering, the participants’ cycling neither helped nor hindered their brain function.
"Unexpected Dual Task Benefits on Cycling in Parkinson Disease and Healthy Adults: A Neuro-Behavioral Model" (Public Library of Science)