Table 3.

Effect of Met and GAA supplementation on urinary output and plasma concentrations of GAA, creatine, and creatinine

	0 Met			6 g/d Met
	GAA, g/d							P-value 1
Item	0	7.5	15	0	7.5	15	SEM	Met	G-L	G-Q	Met × G-L	Met × G-Q
n	7	7	7	7	6	6
Urinary, g/d
GAA	0.52	0.74	0.70	0.67	0.62	0.66	0.17	0.97	0.15	0.40	0.14	0.11
Creatine	5.7	7.8	7.1	6.7	6.1	6.5	1.5	0.41	0.33	0.39	0.18	0.07
Creatinine	5.7	7.9	6.9	6.3	6.6	6.9	1.6	0.61	0.13	0.14	0.55	0.13
Plasma, mg/L
GAA	0.45	0.58	0.63	0.45	0.62	0.61	0.046	0.84	<0.01	0.02	0.73	0.43
Creatine	23.8	24.9	26.2	21.1	22.5	24.9	1.1	<0.01	<0.01	0.58	0.20	0.73
Creatinine	6.62	6.94	6.63	6.55	6.52	6.53	0.3	0.32	0.97	0.35	0.94	0.31
Renal reabsorption, %
GAA	−50.1	−28.0	−20.5	−43.9	−12.6	−11.7	19.6	0.64	<0.01	0.22	0.90	0.67
Creatine	71.5	71.0	73.5	66.8	70.3	75.6	2.9	0.61	0.01	0.52	0.11	0.87

¹G-L, linear effect of GAA; G-Q, quadratic effect of GAA.