A research team led by a scientist at the University of California, Riverside, has found olfaction — or smell — may play an important role in motivating mammals to engage in voluntary exercise.

Performed in lab mice, the study may open up new areas of research and have relevance for humans. Study results appear in PLOS ONE.

“Exercise, which is essential for both physical and mental health, can help prevent obesity and other inactivity-related diseases and disorders in humans,” said Sachiko Haga-Yamanaka, an assistant professor of molecular, cell and systems biology at UC Riverside and the study’s lead author. “Some people like to exercise more than others do, but why this is so is not well understood.”

To determine genetic contributions to voluntary exercise-related traits, Haga-Yamanaka and her team subjected mice to voluntary wheel running, or VWR, a widely studied behavior in which rodents run spontaneously when given access to running wheels.

Her collaborator and co-author Theodore Garland Jr., a distinguished professor of evolution, ecology, and organismal biology at UCR, established independent, artificially evolved mouse lines by selectively breeding mice showing high VWR activity. Regular mice — those not genetically engineered in any way — constituted the controls. To their surprise, the researchers found high-runner mice developed genetic differences in their olfactory system that made them perceive smells differently from the controls.

Next, the researchers plan to conduct experiments to isolate particular chemicals produced by mice, perhaps from their urine, and determine if and how these chemicals increase motivation for exercising.

Haga-Yamanaka and Garland were joined in the research by Quynh Anh Thi Nguyen, David Hillis, Timothy Harris, and Crystal Pontrello of UCR; and Sayako Katada of Kyushu University in Japan.

The study was partly funded by the National Science Foundation.

The research paper is titled “Coadaptation of the chemosensory system with voluntary exercise behavior in mice.”

This UCR News article was written by Iqbal Pittalwala and can be viewed here.