“…11 Numerous endeavors have employed 31 P MRS in the brain, heart, and muscle, seeking out alterations in neurodegenerative, cardiovascular, metabolic, and oncological diseases. [12][13][14][15][16][17][18][19][20] While relevant 1 H-MRS metabolite signals are obscured by background signals such as contaminating fat, water, and macromolecular signals, widely spaced 31 P spectral peaks can be easily elucidated due to the absence of these nuisance signals. However, in contrast to 1 H-MRS, 31 P-MRS is burdened by a lower gyromagnetic ratio and relatively short spin-spin metabolite relaxation times (T 2 ); 21,22 these factors engender extremely poor in vivo relative sensitivity and force a delicate balance between SNR, resolution, and scan duration.…”