Fig. 3.

(A) Photograph of experimental setup for the in vivo ³¹P MRS study of the human calf muscle with the placement of four uHDC blocks around the subject’s leg. In vivo ³¹P CSI profiles with the uHDC blocks at a RF pulse reference voltage of 63 V (B), and without the blocks at a reference voltage of 141 V (C). (D) Comparison of in vivo ³¹P spectra acquired using the small ³¹P surface coil at a reference voltage of 60 V, and the ³¹P volume coil with (E) and without the uHDC blocks (F).