On Monday afternoon, Marius Locke explained to a group of about 30 why exactly exercise and cutting down calories are good for you. Locke, who is an associate professor in the Faculty of Physical Education and Health, spoke as part of the Monday Afternoon Research Series. The two-year-old speaker series invites professors from U of T and other schools to lecture on their specialties, giving students an opportunity to hear about research and meet academics in the field.

Locke’s research focuses on cellular response to exercise and what happens to heat shock proteins in muscles. Heat shock proteins (they also go by stress proteins) are found in almost all living organisms. HSPs act as the cell’s chaperone and are believed to regulate important cellular functions. They protect cells and tissues, such as when cells are exposed to heat, cold, and oxygen deprivation, and rapidly express and induce a stress response.

“The cell has its own system for protecting itself,” said Locke. “Stress can happen at the cellular level, just as it can happen at the organismic [sic] level.” While some amount of stress is necessary, certain types of stress cause specific protein damage and can also trigger the accumulation of these damaged proteins.

What does this have to do with the secret to long life? Boosted HSP activity is found in people who exercise or cut down on calories, while still obtaining optimum levels of nutrients to sustain themselves. “Calorie restriction is the only known protection of inducing the longevity of animals,” said Locke. It also delays or prevents age-associated diseases and has an anti-aging effect.

But there is a “bad” side to HSPs, Locke said. “When the stress proteins are inside the cell, they are friendly and protective. Outside the cell they are quite the opposite and can be said to be inflammatory.”

Extracellular HSPs tend to react with receptors to cause inflammation. They can also interact with immune cells, along with other cells and tissues.

The next Monday Afternoon Research Series takes place on Nov. 2, with “Sport for development: Pessimism of the intellect, optimism of the will” by Fred Coalter from the University of Stirling, Scotland.

For more information on upcoming talks, visit physical.utoronto.ca