Effects of exercise on resting-state default mode and salience network activity in overweight/obese adults.

Despite the common use of exercise as a weight-loss strategy, little is known about its neuronal effects, and how these may be related to cognitive changes that impact food intake. The current study assessed the effects of a 6-month exercise intervention on intrinsic activity in the default mode network (DMN), a functionally connected network of brain regions including posterior cingulate cortex, cuneus/precuneus, medial prefrontal cortex, medial temporal lobe, and inferior parietal cortices, and salience network, which includes the anterior cingulate cortex and insula. Resting-state functional MRI data were acquired in 12 overweight/obese individuals. The intervention was associated with a reduction in DMN activity in the precuneus (P=0.003, family-wise error-corrected), which was associated with greater fat mass loss (P=0.013) as well as reduced perceived hunger (Three Factor Eating Questionnaire, P=0.024) and hunger ratings in response to a meal (P=0.013). No changes were observed in the