Table 1 Cardiopulmonary and running performance variables measured in 12 Thoroughbreds during and at the end of a period of initial training

Body mass (M_b) (kg)

417 ± 19^ab

401 ± 39^cd

384 ± 24^ef

490 ± 8^a

456 ± 25^c

456 ± 22^e

461 ± 32^b

445 ± 35^d

444 ± 14^f

Max running speed (m/s)

12.4 ± 0.3^a

12.3 ± 0.3^b

12.1 ± 0.2^c

12.4 ± 0.2^d

12.7 ± 0.5^b

13.5 ± 0.1*^c

13.4 ± 0.2*^ad

V o₂max / M_b (ml O₂ (STPD)/(min kg)

133 ± 3^a

127 ± 5^b

131 ± 2^c

149 ± 12*^d

148 ± 9^b

158 ± 10^c

172 ± 16*^ad

HR (beat/min)

243 ± 4

231 ± 3

239 ± 4^c

237 ± 11

222 ± 2

224 ± 5^c

228 ± 3

_{Q (1/min)}

260 ± 31

305 ± 5

310 ± 35

315 ± 32

326 ± 27

328 ± 22

329 ± 43

Q/M_b(ml/min kg)

676 ± 44

622 ± 14^a

680 ± 40

690 ± 53

707 ± 40^a

739 ± 41

739 ± 73

V_S (l)

1.07 ± 0.14^a

1.32 ± 0.04^b

1.30 ± 0.15^c

1.33 ± 0.11

1.47 ± 0.11^b

1.47 ± 0.10^c

1.44 ± 0.19^a

V_S/M_b (ml/kg)

2.79 ± 0.21

2.70 ± 0.09^a

2.84 ± 0.19^b

2.92 ± 0.20^c

3.18 ± 0.16^a

3.30 ± 0.17^b

3.24 ± 0.32^c

[Hb] g/dl

18.2 ± 1.4^a

18.8 ± 0.6

18.7 ± 0.4^b

19.5 ± 1.6 ^c

19.4 ± 0.8

19.6 ± 0.1^b

21.6 ± 0.8*†^ac

PCV (%)

48.3 ± 3.1^a

52.0 ± 0.8

53.5 ± 2.6

52.3 ± 3.0^b

53.0 ± 1.2

54.6 ± 0.5

57.5 ± 2.6*†^ab

C_aO₂ (ml O₂ (STPD)/d

21.6 ± 0.6^a

22.8 ± 1.1

23.3 ± 0.7

23.0 ± 1.0^b

22.8 ± 2.1

23.6 ± 0.8

25.6 ± 1.8^ab

$C_{\overline{\mathrm{v}}}{\mathrm{O}}_2\left(\mathrm{ml}{\mathrm{O}}_2\left(\mathrm{STPD}\right)/\mathrm{dl}\right)$

1.9 ± 0.7

2.4 ± 0.1

2.8 ± 0.3

1.4 ± 0.5*†

2.4 ± 0.5

2.3 ± 0.4

2.0 ± 0.4 *

S_aO₂ (%)

88.0 ± 4.3

87.1 ± 4.3

91.9 ± 2.1

86.7 ± 5.1

91.0 ± 5.4

89.35 ± 3.1

85.7 ± 2.6

$S_{\overline{\mathrm{v}}}{\mathrm{O}}_2\left(\%\right)$

8.1 ± 3.6

9.3 ± 2.8

11.2 ± 1.4

6.8 ± 3.3

10.1 ± 1.8

8.8 ± 1.8

6.8 ± 1.2

[LA] (mmol/l)

12.6 ± 1.3

18.3 ± 4.8

15.0 ± 1.7

14.6 ± 5.3

15.8 ± 2.6

16.2 ± 2.9

17.2 ± 4.1

V₂₀₀ (m/min)

613 ± 66

652 ± 70

696 ± 30