Effects of shoeing on intra- and inter-limb coordination and movement consistency in Icelandic horses at walk, tölt and trot.

This study investigates how the practice of keeping Icelandic horses’ hooves high and long for competitive performances impacts their walking and trotting movements. It finds that while it enhances the rhythm of the horse’s unique “tölt” gait, it disrupts the consistency of other movements and could potentially negatively affect the health of the horse’s feet.

Study Methodology and Details

• The study examined thirteen Icelandic horses that were conditioned to exercise with a rider on a treadmill. The researchers studied these horses in two circumstances – when their hooves were kept long and high, like they are for competition (S(H)), and when they were trimmed normally (S(N)).
• By using an instrumented treadmill, the researchers were able to collect data on the vertical ground reaction force (GRF) curves of the horses, from which they obtained information about limb timing variables.
• These measurements were taken when the horses were walking, when they were “tölting” (a four-beat lateral ambling gait unique to Icelandic horses) at two different speeds, and when they were trotting at two different speeds.

Findings of the Study

• The extended hooves (S(H)) resulted in a slower stride rate and extended breakover duration (the phase in a horse’s stride where its hoof is leaving the ground) for all gait types.
• In the tölt gait, the footfall rhythm displayed less propensity to form lateral couplets — a gait characteristic in which both legs on one side of the horse move together.
• In terms of the stride-to-stride variability at the tölt, the extended hooves resulted in an increase in the variability of certain timing parameters either at higher speeds or in general.
• At faster trotting speeds, extended hooves led to a decrease in the variability of the ‘duty factor’ of the hind legs (the proportion of one stride duration for which the foot is on the ground) but increased the variability of the duration of the contralateral step in the forelegs (one foot is off the ground while the other is on the ground).

Implications of the Results

• While high hooves with long toes can enhance the distinct rhythm of the tölt, they also disrupt the consistency of the horse’s other movements.
• The prolonged duration of breakover observed in all gaits can potentially have negative health implications, particularly for the structures at the back of the horse’s foot.

Conclusion

• While the modification of shoes may serve aesthetic or performance purposes in the short term, the long-term effects on the horse’s motor coordination and potential deleterious health effects suggest a need for reconsideration or modification of this practice.