Table 2

Physiologic parameters across 4 months of acclimation

Month 1: 24°CMonth 2: 19°CMonth 3: 24°CMonth 4: 27°CPtrend
24°C19°C24°C19°C24°C19°C24°C19°C24°C19°C
Total EE (kcal)2,472 ± 1802,624 ± 198a2,366 ± 3582,543 ± 410a2,400 ± 2522,555 ± 346a2,341 ± 2552,505 ± 322a0.450.46
Respiratory quotient0.84 ± 0.030.84 ± 0.010.84 ± 0.020.83 ± 0.020.85 ± 0.020.84 ± 0.020.84 ± 0.030.85 ± 0.020.720.47
Total activity (units)8.4 ± 1.68.4 ± 2.87.6 ± 2.97.1 ± 2.46.8 ± 3.77.1 ± 4.17.9 ± 5.07.2 ± 4.70.540.38
Surface electromyography (×10−6 RMS)2.8 ± 0.42.5 ± 1.32.7 ± 0.32.6 ± 0.22.8 ± 0.52.7 ± 0.22.8 ± 0.32.6 ± 0.40.980.83
CIT (%)6.2 ± 4.17.4 ± 3.16.2 ± 3.96.8 ± 3.20.16
DIT (%)10.3 ± 13.133.4 ± 18.219.0 ± 15.442.2 ± 17.4a,b19.1 ± 16.037.1 ± 19.6a22.5 ± 11.034.4 ± 19.2a0.300.36
  • Data are means ± SD. At the end of each testing month, subjects underwent acute thermometabolic evaluation at either 24°C or 19°C. RMS, root mean square.

  • aP < 0.05 compared with 24°C during acute thermometabolic evaluation each month;

  • bP < 0.05 (month 1 vs. 2) compared with matching measurement at same temperature performed at respective months as indicated.