Table 3.

Calf Muscle High‐Energy Phosphate Metabolism Parameters Measured With ³¹P‐MRS at Rest and After Exercise in Healthy Control Subjects and Peripheral Artery Disease Patients

	Healthy control subjects (n = 15)	Peripheral artery disease patients (n = 13)
PCr (mM)
rest	34.6 ± 2.6	35.5 ± 3.2
end‐exercise	25.1 ± 3.7	23.9 ± 5.7
PCr depletion (%)	27.6 ± 7.9	36.1 ± 11.9*
τPCr (s)	30.3 ± 9.7	52.0 ± 13.5***
Pi (mM)
rest	5.1 ± 1.1	6.0 ± 1.6
end‐exercise	13.2 ± 2.7	16.0 ± 4.1
PDE (mM)
rest	5.4 ± 1.5	4.6 ± 0.8
end‐exercise	4.8 ± 1.4	3.2 ± 1.5**
ADP (mM)
rest	10.3 ± 0.9	10.3 ± 1.2
end‐exercise	35.4 ± 7.6	47.6 ± 29.6
pH (–)
rest	7.06 ± 0.03	7.07 ± 0.05
end‐exercise	7.05 ± 0.05	7.06 ± 0.04

ADP, adenosine diphosphate; PCr, phosphocreatine; PDE, phosphodiesters; P_i, inorganic phosphate; τ_PCr, PCr recovery time constant.

^* P < 0.05; **P < 0.01; ***P < 0.0001 vs. healthy control subjects (two‐sided Mann–Whitney U‐test).