Table 1.

³¹P-MRS data from calf muscle of FRDA patients, controls, and disease

Case no.	n of GAA repeats in the smaller allele	Rest, [Pi] (mM)	End-exercise, [ADP] (μM)	Recovery
				V (mM/min)	Vmax (mM/min)
1	900	5.5	46	6	10
2	590	5.1	98	18	24
3	890	4.1	25	5	11
4	540	3.4	86	12	16
5	460	5.2	29	10	20
6	650	4.6	72	11	16
7	290	5.1	54	16	25
8	450	4.1	47	12	19
9	630	4.0	51	11	18
10	780	3.5	69	11	16
11	620	5.1	59	7	11
12	400	4.5	58	11	17
	FRDA patients (n = 12)	4.5 ± 0.7	58 ± 21	11 ± 4	17 ± 5
	Controls	3.9 ± 0.7	58 ± 17	33 ± 12	51 ± 16
	(n = 18)	(2.4–4.9)	(25–94)	(19–60)	(27–82)
	(FRDA vs controls)	P, 0.01	P, 0.3	P, 0.0001	P, 0.0001
	Disease controls (DC) (n = 12)	4.7 ± 1.6	75 ± 24	33 ± 13	48 ± 18
	(FRDA vs DC)	P, 0.7	P, 0.07	P, 0.0001	P, 0.0001

ADP, free cytosolic; V, initial rate of PCr postexercise resynthesis; V_max, maximum rate of mitochondrial ATP production. Data are expressed as mean ± SD (range).