Interaction of saddle girth construction and tension on respiratory mechanics and gas exchange during supramaximal treadmill exercise in horses.

The research studies the effects of different saddle girths and their tightness on a horse’s respiratory system during high-intensity exercise. It finds no significant impact on gas exchange and breathing mechanics, but suggests tension might affect horse performance through muscle compression.

Research Methodology

• The researchers used six healthy Thoroughbred horses who were previously trained but currently not in training for the study.
• Experiments were conducted on a treadmill set to an inclination of 10% at an exercise intensity of 110% of the horses’ maximal oxygen consumption (VO2max).
• Measurements related to the horse’s respiratory mechanics and gas exchange were taken at intervals during the exercise test. The horses were first exercised for two minutes at 40% VO2max, with data recorded at one minute 45 seconds. The speed was then increased to 110% VO2max, with measurements taken at 45 seconds, 90 seconds, and every 30 seconds thereafter until the point of exhaustion.
• The horses were run on three different instances using the same saddle but different girths – one elastic and one standard canvas which is nonelastic. Each horse also underwent a control run with a standard canvas girth at a tension of 5 kg. Additional runs were conducted at a higher tension of 15 kg using both types of girths.
• The order of the runs and the tension of the girths were randomized and measured at the end of each exhalation while the horses were at rest.

Results and Conclusions

• Results indicated that changing the girth tension was not associated with alterations in the horses’ respiratory mechanics or gas exchange properties.
• Girths tightened to 15kg tension may have resulted in shorter run to fatigue times, but this was not determined to be significantly different from girths set at 5kg resting tension.
• Girth tensions decreased at the end of an exhalation in horses nearing exhaustion.
• Performance loss seen in correlation with high girth tensions might not be due to alterations in respiratory mechanics but could be related to the suboptimal working length of the inspiratory muscles due to the compression of the thorax or musculature around the chest. But, these changes were not reflected in the measured alterations in respiratory mechanics or gas exchange properties during high-intensity exercise.
• Other factors may cause early fatigue when horses exercise with tighter girths. Further research is needed to identify why overly tight girths can negatively affect a horse’s performance.