. 2020 Jul 27;598(18):3859–3870. doi: 10.1113/JP277619

Table 3.

Measured and calculated muscle metabolites at rest (0 min), and after 30 min and 120 min of steady‐state exercise at ∼ 65% of ${\dot{V}}_{O_{2} peak}$

Metabolite			0 min	30 min	120 min
Lactate	Untrained	^§	4.6 ± 1.2	11.9 ± 3.4	27.5 ± 11.6^*
(mmol kg⁻¹ dm)	Trained	^§‡	3.8 ± 2.1	8.9 ± 3.6	11.6 ± 4.9
PCr	Untrained	^§	70.1 ± 15.5	46.1 ± 12.8	42.9 ± 11.5
(mmol kg⁻¹ dm)	Trained	^§‡	78.9 ± 13.7	61.5 ± 17.0	56.6 ± 13.8
Cr	Untrained	^§	38.5 ± 7.0	61.4 ± 18.3	69.7 ± 17.6
(mmol kg⁻¹ dm)	Trained	^§‡	39.1 ± 6.1	55.1 ± 11.1	58.8 ± 15.9
PCr:(PCr + Cr)	Untrained	^§	0.64 ± 0.07	0.44 ± 0.12	0.37 ± 0.13
	Trained	^§‡	0.66 ± 0.07	0.52 ± 0.12	0.50 ± 0.12
ATP	Untrained		24.3 ± 2.2	24.1 ± 2.5	24.3 ± 3.5
(mmol kg⁻¹ dm)	Trained		24.4 ± 4.1	26.5 ± 6.2	24.1 ± 3.0
ADP_free	Untrained	^§	131 ± 36	338 ± 239	409 ± 199
(μmol kg⁻¹ dm)	Trained	^§	109 ± 20	228 ± 66	248 ± 117
AMP_free	Untrained	^§	0.8 ± 0.5	2.3 ± 0.8	13.5 ± 4.1^*
(μmol kg⁻¹ dm)	Trained	^§‡	0.6 ± 0.3	2.4 ± 1.5	3.2 ± 2.6
AMP_free:ATP	Untrained	^§	0.04 ± 0.02	0.08 ± 0.03	0.56 ± 0.17
	Trained	^§‡	0.03 ± 0.02	0.10 ± 0.07	0.13 ± 0.09

Values are the mean ± SD, n = 11 untrained and 7 exercise trained participants. PCr, creatine phosphate; Cr, creatine; ADP_free, free adenosine diphosphate; AMP_free, free adenosine monophosphate, dm; dry muscle. ^*Significantly different to corresponding trained value. §Main effect for time. ‡Main effect for untrained compared to trained (P < 0.05).