Table 1.

Speed data for horses on the level and up a 10% incline

Level Incline
HorseEOTSTmaxGminEOTSTmaxGmin
Anakin4.965.24±0.49 (7)5.81±0.38 (7)NA4.75±0.14 (7)5.25±0.14 (8)
Austin5.475.17±0.33 (13)6.30±0.32 (17)4.724.47±0.33 (11)5.27±0.43 (17)
GT5.485.56±0.35 (15)6.10±0.42 (12)4.395.14±0.40 (13)5.62±0.42 (12)
Red5.124.92±0.39 (26)5.32±0.41 (28)4.454.03±0.39 (32)4.55±0.35 (30)
Reign4.504.50±0.20 (13)5.34±0.39 (18)4.173.94±0.26 (14)4.67±0.40 (14)
CharlieNA4.56±0.37 (16)4.97±0.41 (16)NA3.94±0.29 (15)4.31±0.33 (15)
MikeyNA5.69±0.39 (16)6.16±0.37 (16)NA4.78±0.41 (19)5.16±0.34 (21)
Mean5.11±0.41a5.09±0.46a5.71±0.51b4.43±0.23c4.44±0.48c4.98±0.47d
  • Speed data (m s-1) are expressed as means ± S.D. N is given in parentheses after each value.

    The speed at which the metabolic rate for trotting was equal to galloping [the energetically optimal transition speed (EOTS)] was not different to the fastest speed at which the horse would trot continuously for 1 min without switching to a gallop [maximum sustained trotting speed (Tmax)]. The EOTS was less (P<0.05; indicated by different superscript letters) than the lowest speed at which the horse would gallop continuously for 1 min without switching to the trot [minimum sustained galloping speed (Gmin)]. On an incline, the speed at the EOTS decreased when compared with the speed on the level (P<0.05; indicated by different superscript letters) as did both the Tmax and the Gmin. The EOTS on the incline was lower than the Gmin. `NA' means not available. For the EOTS of Anakin on the incline, the regression lines for trotting and galloping did not cross, hence there is no speed for which metabolism at the trot equals that at the gallop. Both Mikey and Charlie became lame before metabolic measurements could be made.