Water treadmill exercise reduces equine limb segmental accelerations and increases shock attenuation

Area of Science:

• Equine biomechanics
• Animal rehabilitation

Background:

• Equine water treadmills (WTs) are increasingly used for exercise, offering perceived high resistance and low impact.
• Limited data exists on how water height influences limb loading during WT exercise.

Purpose of the Study:

• To investigate the impact of water height and exercise speed on segmental acceleration and impact attenuation in horses on a water treadmill.
• To quantify limb loading during various water immersion levels and speeds.

Main Methods:

• Three accelerometers were placed on the left forelimb (hoof, mid-cannon, mid-radius) of horses.
• Horses performed walking exercise at two speeds (0.83 m/s, 1.39 m/s) in a water treadmill at three heights (mid-cannon, carpus, stifle) and a dry control.
• Peak acceleration, impact attenuation, and stride frequency were analyzed using linear mixed effects models.

Main Results:

• Peak acceleration was significantly lower in all limb segments with any water height compared to dry conditions.
• Higher water levels, specifically at the stifle, resulted in greater reductions in acceleration and increased impact attenuation compared to mid-cannon water height.
• Water immersion demonstrably reduced segmental accelerations and enhanced impact attenuation.

Conclusions:

• Water treadmill exercise effectively reduces limb acceleration and increases impact attenuation in horses.
• The findings suggest that water treadmill exercise, particularly with higher water levels, may be a valuable therapeutic modality for equine lower limb injuries.