Exercise-induced changes of macromolecular content in calf muscles quantified with T1ρ magnetic resonance imaging

Exercise could induce changes in skeletal muscle’s macromolecular content. In this study, we used an exercise-then-imaging protocol to verify and characterize such phenomenon for calf muscles of healthy subject. A T1ρ mapping technique was used for imaging calf muscles before and after planter flexion of different loads. It was found that post-exercise increases in T1ρ values of gastrocnemius and peroneus longus at exercise load of 16 and of 20 lbs were significantly higher than that of 8 lbs. In conclusion, T1ρ is sensitive to changes of macromolecular content in calf muscles induced by plantar flexion of moderate or high intensity.