TABLE 1

Characteristics of Study Groups

Variable	PET during fasting: normal IS	PET during clamp			PET during fasting and clamp: low IS
Variable	PET during fasting: normal IS			Normal IS	PET during fasting and clamp: low IS	High IS
n	7	9	8	7
Age (y)	34 ± 8	28 ± 4	28 ± 2	62 ± 9*
EF (%)	—	62 ± 6	65 ± 3	62 ± 8
Weight (kg)	82 ± 9	77 ± 9	76 ± 6	81 ± 10
Height (cm)	181 ± 7	182 ± 5	186 ± 4	179 ± 5^†
Fasting plasma levels
Glucose (mmol·L⁻¹)	5.4 ± 0.5	5.2 ± 0.3	5.3 ± 0.4	5.2 ± 0.5
Insulin (pmol·L⁻¹)	18 ± 15^‡	45 ± 15	30 ± 18	44 ± 16
FFA (mmol·L⁻¹)	0.70 ± 0.23^†	0.54 ± 0.19	0.39 ± 0.12	0.67 ± 0.17^†
Clamp plasma levels
Glucose (mmol·L⁻¹)	—	5.1 ± 0.8	5.1 ± 0.3	5.4 ± 0.8
Insulin (pmol·L⁻¹)	—	420 ± 100^§	430 ± 160^§	460 ± 120^§
FFA (mmol·L⁻¹)	—	0.11 ± 0.04^§	0.10 ± 0.03^§	0.07 ± 0.03*^§
M (μmol·min⁻¹·kg⁻¹)	—	35 ± 7	65 ± 8^‖	24 ± 3^†^‖

↵* P < 0.05 vs. other groups.
↵^† P < 0.05 vs. high IS.
↵^‡ P < 0.05 vs. normal IS (PET during clamp) and low IS.
↵^§ P < 0.05 vs. fasting.
↵^‖ P < 0.05 vs. normal IS during clamp.
M = whole-body glucose utilization, which was computed during steady-state phase of clamp; EF = ejection fraction.