Table 2

Plasma hormone and metabolite concentrations at a thermoneutral temperature and during exposure to mild cold, before and after cold acclimation

VariableBefore cold acclimationAfter cold acclimation
ThermoneutralMild coldΔThermoneutralMild coldΔ
NEFA (μmol/L)501 ± 145539 ± 17834 ± 89477 ± 155517 ± 17440 ± 123
Triglycerides (μmol/L)1,585 ± 6531,966 ± 824381 ± 6001,644 ± 9321,924 ± 1,033*280 ± 177
Glucose (mmol/L)5.0 ± 0.34.7 ± 0.4*−0.30 ± 0.25.2 ± 0.54.8 ± 0.3*−0.4 ± 0.3
Insulin (μU/mL)12.2 ± 3.312.4 ± 3.50.2 ± 2.114.2 ± 4.312.9 ± 4.9−1.3 ± 1.4
TSH (units/mL)1.5 ± 0.81.4 ± 0.7−0.1 ± 0.21.5 ± 0.71.4 ± 0.6−0.1 ± 0.1
Free T4 (pmol/L)13.3 ± 2.213.2 ± 1.7−0.1 ± 1.112.7 ± 1.712.8 ± 1.80.0 ± 0.7
Norepinephrine (nmol/L)1.7 ± 0.43.2 ± 1.0*1.5 ± 0.92.0 ± 1.13.3 ± 1.51.2 ± 1.5
Epinephrine (nmol/L)0.12 ± 0.040.11 ± 0.04−0.01 ± 0.060.13 ± 0.050.10 ± 0.05−0.03 ± 0.05
  • Data are expressed as mean ± SD. NEFA, nonesterified fatty acid; TSH, thyroid-stimulating hormone; T4, thyroxine.

  • *P < 0.01,

  • P < 0.05, mild cold vs. thermoneutral conditions.