TABLE 3.

AUC of breath ¹³CO₂ enrichment and V¹³CO₂after infusion with [1,2-¹³C]glycine or [1-¹³C]glycine and [²H₃]leucine¹

	Protocol [1,2-13C]glycine	Protocol [1-13C]glycine	Difference
AUC of 13CO2 enrichment, mol % excess over 6 h	0.0347 ± 0.0041	0.0244 ± 0.0032	0.0103 ± 0.0034*
AUC of V13CO2, μmol·h−1·kg−1 over 6 h	2.46 ± 0.52	1.62 ± 0.23	0.84 ± 0.65‡
VCO2, μmol·h−1·kg−1	5383 ± 460	5772 ± 678

¹Values are mean ± SD, n = 6. Symbols indicate difference: *P < 0.001; ^‡P = 0.025 (2-sided paired t test).