The Effect of Stirrup Iron Style on Normal Forces and Rider Position.

The research article examines whether different types of stirrup irons affect the forces endured by a horse and its rider, and whether they influence the rider’s position and interaction with the horse. The study did not find significant differences among traditional, flexible, or flexible and rotatable stirrups regarding joint angles, toe position, or forces induced. However, the forces did vary with different gaits.

Methodology

• Four riders participate in the study, using three different types of stirrups: Traditional (T), Flexible (F), and Flexible and rotatable (FR).
• Riders’ hip, knee, and ankle angles, as well as toe position were filmed and analyzed.
• Force exerted on the stirrups was evaluated using force sensors situated on the stirrups’ threads.
• Both the highest point (HP) and lowest point (LP) of the posting trot were evaluated, with four instances counted for each situation.
• The forces endured during the canter were registered twice.
• The study used Shapiro-Wilk’s test, Friedman’s test, and Wilcoxon signed rank test to conduct statistical analyses, with significance swaged at P less than .05.

Results

• The joint angles, toe positions, and forces did not show significant differences among the three different stirrup types.
• The mean hip, knee, and ankle angles measured at the HP were 169.4°, 150.7°, and 94.5°, respectively, while at the LP these measures registered 139.1°, 123.9°, and 92.7°, respectively.
• There was a notable difference of 8.74° in joint angles of the rider’s right side versus the left.
• Right toes tended to rotate more laterally, regardless of the type of stirrup used.
• Mean trot forces applied in relation to the body weight were 0.72 at HP, 0.19 at LP, and 0.18 during the canter.
• Riders were found to shorten the stirrup leathers when using flexible or flexible and rotatable stirrups.

Conclusion

• The findings indicated that stirrup style has minimal impact on the rider’s position and the forces experienced both by the horse and rider.
• The research also revealed that while the type of stirrup did not significantly affect the forces, the gait did.
• The study suggests that further inquiries should be made regarding how a rider’s experience and possible painful joints might contribute to asymmetries in riders.