Table 2. Serum electrolyte concentrations, body temperature, and heart rate during exercise. Values are mean (SD) for 7 subjects.
NF VF PF FF
Serum sodium (mmol·L-1)
  Pre 138 (2) 139 (2) 139 (3) 138 (1)
  Post 142 (2) § 139 (2) 139 (2) 138 (1) † 
Serum potassium (mmol·L-1)
  Pre 3.5 (0.2) 3.6 (0.3) 3.6 (0.2) 3.6 (0.2)
  Post 4.1 (0.3) § 4.2 (0.3) § 4.0 (0.2) 4.0 (0.3)
Serum chloride (mmol·L-1)
  Pre 104 (1) 104 (2) 104 (1) 104 (2)
  Post 106 (2) 103 (2) 103 (1) 102 (2) † 
Tre (°C)
  Rest 37.0 (0.2) 37.0 (0.2) 37.0 (0.2) 36.9 (0.2)
  End of exercise 38.8 (0.3) 38.3 (0.3) †  38.2 (0.2) †  37.9 (0.2) † 
Tsk (°C)
  Rest 33.7 (0.5) 33.6 (0.7) 33.5 (0.6) 33.5 (0.6)
  End of exercise 34.9 (1.0) 34.9 (0.9) 34.4 (0.8) 34.4 (0.9)
HR (beats·min-1)
  Rest 83 (5) 84 (5) 88 (5) 90 (6)
  End of exercise 181 (9) 167 (8) * 164 (10) †  154 (11) † 
‡ p < 0.05 denotes a significant difference from the VF trial.†  p < 0.01 denotes a significant difference from the NF trial.* p < 0.05 and T, rectal temperature; T, mean skin temperature; HR, heart rate.§ p < 0.01 denotes a significant difference from pre-exercise.