Metabolic Stability and Athletic Output
High performance does not begin in the arena.
It begins in the bloodstream.
Before a horse can express power, suspension, impulsion, and willingness, its metabolic system must be stable. When glucose regulation fluctuates, insulin remains elevated, or vascular tone becomes inconsistent, performance capacity declines long before lameness appears.
Athletic expression is not separate from physiology. It is dependent on it.
The Horse as a Fibre-Fermenting Athlete
The horse evolved as a continuous grazer, designed to extract steady energy from fibre fermentation in the hindgut. This produces a slow, predictable release of volatile fatty acids, which support stable energy output without sharp glycaemic spikes.
When feeding strategies shift toward high starch concentrates or uncontrolled high sugar pasture intake, blood glucose patterns change. Insulin rises more frequently and remains elevated longer.
Repeated insulin elevation does not simply affect fat deposition.
It alters vascular regulation.
The lamellae are highly vascular structures. So are muscles, tendons, and neural tissues.
Metabolic instability affects them all.
Insulin, Vascular Tone, and Performance
Insulin is not just a glucose transport hormone. It also influences endothelial function and vascular tone.
When insulin remains chronically elevated:
• Microvascular perfusion can become inconsistent
• Inflammatory signalling increases
• Tissue oxygen delivery may be altered
• Lamellar integrity becomes more vulnerable
Even without overt laminitis, subtle vascular changes can reduce mechanical efficiency.
The result may not be visible pain.
The result may be reduced output.
The Cost of Glycaemic Volatility
Horses performing athletic work require predictable energy availability.
Large fluctuations in blood glucose create:
• Inconsistent energy delivery
• Altered neuromuscular coordination
• Reduced cognitive focus
• Increased stress reactivity
Owners often describe these horses as “up and down,” “hot one day and flat the next,” or “unwilling without explanation.”
Stable fermentation based energy supports consistent output.
Volatile starch based energy produces inconsistency.
Forelimb Comfort and Whole Body Expression
Athletic movement begins with forelimb loading.
Even mild lamellar stress alters breakover timing and load distribution. When the forelimbs are not fully comfortable, the horse cannot confidently transfer power from the hindquarters through the thoracic sling.
Engagement decreases.
Collection suffers.
Stride symmetry alters.
This is why metabolic stability and hoof health cannot be separated from performance discussion.
A horse protecting its front end cannot fully express athletic potential.
Cold-Adapted and Easy-Keeping Breeds
Certain breeds evolved to survive harsh climates on sparse forage. They developed efficient metabolic systems capable of extracting significant energy from fibre while conserving calories.
When these horses are exposed to high energy modern pasture and starch dense feeds, their metabolic efficiency becomes a liability.
They gain condition rapidly.
Insulin dysregulation risk increases.
Performance declines before overt disease appears.
Breed type must inform feeding strategy.
The Discipline Advantage
Stable horses are predictable horses.
Predictable horses are trainable horses.
When feeding strategies support steady fermentation, appropriate forage dominance, and controlled starch exposure, metabolic stability improves.
With stability comes:
• Consistent impulsion
• Improved focus
• Reduced stress reactivity
• More reliable performance
Athletic expression is not created by pushing harder.
It is unlocked by stabilising physiology.
The Strategic Question
When performance declines, the first question should not be:
“How do I train harder?”
It should be:
“Is this horse metabolically stable?”
Training pressure applied to physiological instability rarely produces progress.
It produces compensation.