High cardiorespiratory fitness (CRF) is an important protective factor reducing the risk of cardiac-related disability and mortality. Recent research suggests that high CRF also has protective effects on the brain's macrostructure and functional response. However, little is known about the potential relationship between CRF and the brain's white matter (WM) microstructure. This study explored the relationship between a comprehensive measure of CRF (VO 2 peak, total time on treadmill, and 1-minute heart rate recovery) and multiple diffusion tensor imaging measures of WM integrity. Participants were 26 healthy community dwelling seniors between the ages of 60 and 69 (mean=64.79years, SD=2.8). Results indicated a positive correlation between comprehensive CRF and fractional anisotropy (FA) in a large portion of the corpus callosum. Both VO 2 peak and total time on treadmill contributed significantly to explaining the variance in mean FA in this region. The CRF-FA relationship observed in the corpus callosum was primarily characterized by a negative correlation between CRF and radial diffusivity in the absence of CRF correlations with either axial diffusivity or mean diffusivity. Tractography results demonstrated that portions of the corpus callosum associated with CRF primarily involved those interconnecting frontal regions associated with high-level motor planning. These results suggest that high CRF may attenuate age-related myelin declines in portions of the corpus callosum that interconnect homologous premotor cortex regions involved in motor planning.
|Number of pages||10|
|State||Published - Jan 16 2012|
Bibliographical noteFunding Information:
This study was supported by NIH Grant AG03303 , NSF Grant BCS 0814302 , and an internal grant from the University of Kentucky's Clinical Research Development and Operations Center (CR-DOC). We thank CR-DOC's Functional Assessment and Body Composition Core Laboratory for collecting all fitness-related measures. We also thank Dr. David K. Powell, Sara E. Cilles, and Doug E. Long for their assistance in data analysis, recruiting, scanning, and testing participants.
- Brain imaging
- Diffusion tensor imaging
- White matter
ASJC Scopus subject areas
- Cognitive Neuroscience