. 2003 May 23;550(Pt 2):585–603. doi: 10.1113/jphysiol.2003.039743

Table 5.

Net plasma ion and H⁺ fluxes across contracting skeletal muscles at rest and during incremental cycling exercise

Measurement	Rest	30%	65%	75%
Pre-training
[Lac⁻] (mequiv min⁻¹)	0.06 ± 0.41	0.69 ± 0.28	1.58 ± 0.77	2.91 ± 0.53^*^‡
[Cl⁻] (mequiv min⁻¹)	−2.5 ± 3.3	−15.6 ± 10.9	−30.2 ± 9.1^*	−24.4 ± 4.9^*
[Na⁺] (mequiv min⁻¹)	−3.4 ± 4.7	−8.8 ± 15.4	−24.3 ± 12.8	−8.8 ± 5.9
[K⁺] (mequiv min⁻¹)	0.09 ± 0.15	0.82 ± 0.47	1.50 ± 0.65^*	1.49 ± 0.58^*
[H⁺] (nequiv min⁻¹)	4.62 ± 1.29	38.47 ± 8.33^*	54.04 ± 9.83^*	62.36 ± 7.04^*^‡
Post-training
[Lac⁻] (mequiv min⁻¹)	0.04 ± 0.04	0.15 ± 0.15^§	-0.39 ± 0.52^§	0.95 ± 1.15
[Cl⁻] (mequiv min⁻¹)	0.3 ± 1.9	−11.9 ± 6.0	−10.6 ± 2.5^§	−25.3 ± 9.9^*
[Na⁺] (mequiv min⁻¹)	−0.2 ± 2.2	−7.8 ± 7.6	−0.4 ± 4.5^§	−13.7 ± 14.4
[K⁺] (mequiv min⁻¹)	−0.11 ± 0.06	0.02 ± 0.20^§	0.29 ± 0.23^§	0.30 ± 0.31^§
[H⁺] (nequiv min⁻¹)	4.06 ± 1.04	22.98 ± 5.12^*	43.02 ± 3.34^*^‡	92.52 ± 11.99^*^‡^‡^§

Significantly different from rest

^†

significantly different from 30%

^‡

significantly different from 65%

^§

significantly different from pre-training. Data were calculated for 2 legs. A positive value indicates net efflux from the active muscle mass, while a negative value indicates net influx; n = 5 for all analyses.