Exercise-stimulated muscle hyperemia: a preliminary investigation with diffusion tensor imaging on calf muscles

Diffusion tensor imaging (DTI) has been shown to be highly sensitive to subtle pathological alterations caused by multiple diseases. Utilizing this capability of DTI, in this study we characterized post-exercise hyperemic responses of calf muscles. We found that multiple DTI measures, including ADC, λ1-3, and RD, increased significantly in activated muscles, and more than in those in non-activated muscles. Of particular interest was the significant increase in λ3 and RD of the activated muscle, indicating a relatively higher degree of increase in water diffusion along the cross-section direction of muscle fibers.