January 18, 2012 | 9 In addition to helping us get fit, exercise
seems to play a disproportionate role in fending off chronic
diseases, such as diabetes. A new study suggests how activity on
the cellular level might be keeping us healthy when we get
activity on the macro level. The process in question is
autophagy, a series of actions in which cells recycle internal
bits and that, in turn, helps to keep cells agile and able to
adjust to changes in energy requirements and nutritional
conditions. Exercise kicks autophagy—in heart and skeletal
muscles—into high gear in mice. And the new report, published
online Wednesday in Nature, describes how this extra autophagy
seems to help keep insulin resistance (a precursor to diabetes)
at bay in the lab rodents (Scientific American is part of Nature
Publishing Group). The research team, led by Congcong He, of the
University of Texas Southwestern Medical Center, compared mice
that had been genetically engineered so that they did not get
the autophagy boost to regular mi