Table 3.

Thigh carbohydrate metabolism during graded knee extension exercise

	Rest	25% Wmax	65% Wmax	85% Wmax	ANOVA Rest & Ex.	ANOVA Intensity
Femoral arterial glucose conc. (mmol l−1)	4.7 ± 0.1*	4.8 ± 0.2	5.0 ± 0.1	5.0 ± 0.1	†
Glucose delivery (mmol l−1)	1.3 ± 0.1*	11.8 ± 1.4#	17.5 ± 1.7	20.7 ± 2.0$	†	‡
Femoral venous glucose conc. (mmol l−1)	4.5 ± 0.1*	4.7 ± 0.1	4.7 ± 0.1	4.7 ± 0.1	†
Net thigh glucose uptake (mmol min−1)	0.05 ± 0.01*	0.30 ± 0.05#	0.75 ± 0.15	0.98 ± 0.19	†	‡
Thigh glucose extraction (%)	4.3 ± 0.8**	2.5 ± 0.5§	4.1 ± 0.5	5.1 ± 0.4	†	‡
Femoral arterial lactate conc. (mmol l−1)	0.5 ± 0.1***	0.5 ± 0.1#	1.3 ± 0.1	1.3 ± 0.1	†	‡
Femoral venous lactate conc. (mmol l−1)	0.5 ± 0.1***	0.5 ± 0.1	1.3 ± 0.2	1.6 ± 0.2$	†	‡
Femoral venous pH	7.39 ± 0.01***	7.36 ± 0.01#	7.31 ± 0.01	7.30 ± 0.01	†	‡
Net thigh lactate release (mmol min−1)	0.01 ± 0.01 ****	0.16 ± 0.08	− 0.03 ± 0.15	0.88 ± 0.16$	†	‡
Muscle glycogen breakdown	—	50 ± 13§	105 ± 23	165 ± 25	—	‡
(mmol (kg d.w.)−1)
Muscle glycogen breakdown rate	—	1.1 ± 0.3§	3.0 ± 0.7	4.7 ± 0.7	—	‡
(mmol (kg d.w.)−1 min−1)

Data are averaged across each exercise period. The values for Rest and 25% W_max are averaged across both legs. Values are means ± s.e.m.

^*P < 0.05 Rest versus 25, 65 and 85% W_max;

^**P < 0.05 Rest versus 25% W_max;

^***P < 0.05 Rest versus 65 and 85% W_max;

^****P < 0.05 Rest versus 85% W_max.

^†ANOVA effect of exercise intensity including rest.

^‡P < 0.05 ANOVA effect of exercise intensity;

^#P < 0.05 25% W_maxversus 65% W_max and 85% W_max; P < 0.05 25% and 65% W_maxversus 85% W_max;

^§P < 0.05 25% W_maxversus 85% W_max.