Table 2.

Average body mass, V̇o_2max, V̇o₂, respiratory exchange ratio, and cost of transport at a target intensity of 75% V̇o_2max in normoxia ($F{I}_{O_2}$ = 0.2095) for unacclimated F₁ deer mice and in hypoxia ($F{I}_{O_2}$ = 0.12) for hypoxia-acclimated F₁ lowland and highland deer mice

	Normoxia		Hypoxia
	Lowland mice	Highland mice	Lowland mice	Highland mice
Body mass, g	20.5 ± 0.9 (12)	21.6 ± 1.2 (13)†	19.0 ± 0.9 (12)	23.8 ± 1.4 (13)†
V̇o2max, ml/min	3.91 ± 0.18	3.79 ± 0.20	3.05 ± 0.20*	3.47 ± 0.05*
Submaximal running
V̇o2, ml/min	2.99 ± 0.21 (12)	2.88 ± 0.15 (20)†	2.60 ± 0.08 (13)	2.75 ± 0.11 (18)
%V̇o2max	76 ± 4	72 ± 2	82 ± 2	79 ± 3
Speed, m/min	18.9 ± 1.0	23.4 ± 1.4†	17.0 ± 1.2	20.3 ± 0.8*
Respiratory exchange ratio (V̇co2/V̇o2)	0.854 ± 0.011	0.827 ± 0.009	0.849 ± 0.016	0.884 ± 0.018*
Cost of transport, ml/m	0.17 ± 0.02	0.13 ± 0.01†	0.16 ± 0.02	0.14 ± 0.01

Numbers in parentheses are sample sizes for each group. V̇o_2max, maximal O₂ consumption (V̇o₂); V̇co₂, CO₂ production; $F{I}_{O_2}$, fraction of inspired O₂.

^*Significant effect of acclimation within a population;

^†significant effect of population within an acclimation.