Drevemo S, Dalin G, Fredricson I, Björne K
Equine Vet J. 1980 Apr;12(2):71-3. doi: 10.1111/j.2042-3306.1980.tb02312.x.
The reproducibility of certain gait characteristics was investigated in Standardbred trotters at a speed of 12.0 m/sec. Twenty-two horses were recorded twice on the same day and 4 of them on a third occasion 3 years later. The short-term reproducibility was shown to be very good. In the long-term study it was found that the stride length and duration of swing and stride had increased. This was interpreted as an effect of training.