A comparison of the physiological response to tölt and trot in the Icelandic horse.

The study assesses the physiological impact of two different riding styles (tölt and trot) on trained adult Icelandic horses. The main findings include minor variations in heart rate, plasma lactate concentration, respiratory rate, and temperature during recovery, dependent on the riding style.

Study Methodology

• This study used a crossover design, involving 8 horses and 2 riders who each performed two tests per day, with a break of at least 4.5 hours between tests. The tests themselves were performed at different speeds — 3.0 m/s, 4.0 m/s, and 5.0 m/s — and took place on a 300-metre oval gravel riding track in northern Iceland in May 2012.
• Physiological indicators such as heart rate, hematocrit levels (the ratio of the volume of red cells to the total volume of blood), plasma lactate concentrations, respiratory rate, and rectal temperature were measured at several stages: during warm-up, after each phase of the exercise test, and after 5, 15, and 30 minutes of recovery.

Key Findings

• Results found no difference in heart rate between tölt and trot at any phase of testing.
• However, at high speed, the hematocrit levels and plasma lactate concentration were higher in horses performing the tölt gait compared to those performing the trot gait.
• Furthermore, recovery was slower after the tölt gait, indicated by a gradual recovery of hematocrit and respiratory rate, a slower decrease in rectal temperature, and a tendency for plasma lactate concentration to remain higher for longer.

Conclusions

• The study concluded that the physiological response difference between tölt and trot in Icelandic horses is minimal, with only slight elevations in physiological responses to tölt and slower recovery noted.
• However, the biological and practical significance of these slightly elevated physiological responses and the slower recovery after tölt are yet to be determined.
• The findings suggest more research may be necessary to further understand why these differences in physiological response occur between the two gaits and their potential impacts on horse health.