Method for quantifying intramuscular phosphocreatine (PCr) depletion and recovery using ³¹P MRS and the behavior of the creatine CH₂ signal in ¹H MRS

Investigator: Radka Klepochová

In this work, we focused on obtaining information about two key processes at the same time: the depletion and recovery of intramuscular phosphocreatine (PCr) using ³¹P MRS and the behavior of the creatine CH₂ signal in ¹H MRS, which exhibits similar dynamics. While previous studies required separate ¹H and ³¹P measurements with repeated loading, which complicated interpretation, we obtained both types of data for the first time in a single time-resolved interleaved experiment. This approach allowed us to directly compare the kinetics of Cr-CH₂ and PCr during exercise and recovery. We found a very close match between the time constants τPCr and τCr-CH₂, the expected differences between groups with lower and higher BMI were preserved, and we observed a positive correlation between the rate of signal decline. Our results suggest that under certain conditions, the ¹H MRS signal of creatine can be used as a substitute indicator of oxidative capacity, traditionally determined using ³¹P MRS. Based on these findings, we published an article in the Q1 journal NMR in Biomedicine.

Fig. 1: Representative time course of 1H (top) and 31P (bottom) spectra obtained during 3 minutes of rest, 5 minutes of plantar flexion exercise, and 10 minutes of recovery from the calf muscle of one volunteer. Protons and phosphorus, which cause the MRS signal, are highlighted in the structural patterns (P)Cr.

Publications:

KLEPOCHOVÁ, Radka (73%) – NIESS, F. (2%) – METZ, M. (2%) – UKROPCOVÁ, B. (2%) – UKROPEC, J. (2%) – TRATTNIG, S. (2%) – KAUTZKY-WILLER, A. (2%) – KRŠŠÁK, M. (5%) – MEYERSPEER, M. (10%) ¹H and ³¹P MRS interleaved with high time resolution reveals closely matching creatine CH₂ and PCr dynamics during exercise. In NMR in Biomedicine, 2025, vol. 38, no. 10, art. no. e70132. ISSN 0952-3480. (2024: 2.7 – IF, Q1 – JCR, 0.95 – SJR, Q1 – SJR) https://doi.org/10.1002/nbm.70132