Harnessed vs. mounted standardbreds on the track: changes in gait and physiological variables.

The research article highlights that trotting horses under saddle (mounted) requires more energy compared to when they pull a vehicle (harnessed). Even though the pace is slower, the physiological and biomechanical variances observed suggest that trotting mounted is more laborious for the horses and it also alters their gait variables.

Study Methods

• The researchers conducted the study using ten trotters who were selected randomly.
• They performed two standardized exercise tests with these horses. One test was with mounted riders and the other was with the horses harnessed to a vehicle. The weights of the riders and those handling the harness were also standardized to maintain uniformity.
• Several parameters were measured in both types of tests. These included the speed of the horse, the heart rate (HR), the frequency of respiration (RF), concentration of blood lactate (La), and various stride characteristics. The stride characteristics encompassed length, frequency (SF), symmetry, regularity, dorsoventral displacement of the sternum and the three kinds of activities (vertical, lateral, longitudinal) that measured the velocity of acceleration and deceleration.

Results

• After performing paired t-tests and an analysis of variance, the researchers found that speed (both V4 speed for a La of 4 mmol/I and V200 speed for a HR of 200 beats/min), stride length, trot symmetry, lateral activity were lower when the horse was ridden.
• On the other hand, parameters like RF, SF, dorsoventral displacement, vertical and longitudinal activities were significantly higher in ridden horses compared to harnessed horses.

Conclusions

• The research points to the fact that the physiological and biomechanical differences between trotting while harnessed and trotting while ridden indicate a higher requirement of energy in the mounted condition.
• Trotting at maximum speed under saddle is more demanding for the horse. This higher energy requirement is reflected in the reduced V4 and V200 values and the change in gait variables.
• The research concludes by suggesting that trotting while ridden, even at sub-maximum and maximum speeds, necessitates more work for the horse and that this significantly alters some gait variables. The altered gait variables could either be a result of the increased workload, or possibly even a cause of it.