Energetic and kinematic consequences of weighting the distal limb.
Authors: Wickler S J, Hoyt D F, Clayton H M, Mullineaux D R, Cogger E A, Sandoval E, McGuire R, Lopez C
Journal: Equine veterinary journal
Summary
# Editorial Summary Whilst farriers and trainers commonly use weighted shoes to enhance gait animation in performance horses, little was known about the true physiological cost of placing mass at the distal limb rather than on the body proper. Wickler and colleagues measured oxygen consumption and limb kinematics in six horses trotted at speeds between 2 and 5 m/sec, comparing a 2.4 kg load carried on the back against the same mass distributed equally across all four hooves using modified bell boots positioned at the third phalanx. Distal limb loading increased metabolic rate by 6.7%—approximately tenfold greater than back-loading—whilst lengthening stride period by 2% without altering contact time or duty factor; notably, the weighted hooves increased hindlimb range of motion but not forelimb motion. These findings suggest that weighted shoes impose a disproportionate energetic demand on ridden or driven horses, and the associated increase in joint range of motion, particularly in the hind limbs, warrants consideration given the potential for cumulative soft tissue stress and injury in performance animals working at intensity.
Read the full abstract on PubMed
Practical Takeaways
- •Weighted shoes and bell boots intended to enhance animation create disproportionately high metabolic costs compared to equivalent back weight—consider this when advising clients on performance equipment
- •Distal limb weighting alters hindlimb biomechanics more than forelimb mechanics, potentially increasing injury risk through increased joint range of motion
- •The energetic penalty of distal weighting is substantial enough to warrant discussion with owners regarding welfare, fitness demands, and injury prevention in horses using weighted shoes
Key Findings
- •Distal limb loading (2.4 kg at P3 level) increased metabolic rate by 6.7%, approximately 6-7 times greater than back loading
- •Stride period increased by 2% with distal limb weights, but contact time and duty factor remained unchanged
- •Distal limb loading increased range of motion in hindlimbs but not forelimbs
- •Weighted shoes and boots substantially increase metabolic effort and joint range of motion in performance horses