FITNESS IS NOT ONE THING

A horse can become less breathless before every tissue in the body is ready to take on more load. Cardiovascular fitness, muscular conditioning, bone adaptation, tendon capacity and technical skill do not progress as one unit at one pace.

The problem with ‘he feels fit’

Riders often judge fitness by how easily a horse completes a familiar session and how quickly his breathing settles. That information is useful, but it mostly describes developments in one system (the cardiovascular system). The body’s response to training is distributed across several systems, and those systems adapt through different biological processes and on different timelines.

In terms of the systems:

• The cardiovascular system becomes more efficient at delivering oxygen.
• Muscles alter their metabolic and contractile capacity.
• The nervous system becomes more skilled at coordinating a task.
• Bone remodels in response to mechanical strain.
• Tendons and ligaments must tolerate repeated loading while maintaining their highly organised structure.

None of these adaptations can be assumed to have taken place from the improvement of another.

Why tendons deserve particular respect

The superficial digital flexor tendon is a useful example. In fast or demanding work, it stores and releases elastic energy while operating relatively close to its functional limits. Repeated strain can create microscopic damage, and exercise also produces heat within the tendon. A 2021 review described how biomechanical and biothermal effects may contribute to progressive microdamage.

Microdamage is not the same as a clinical tendon injury. Normal tissues experience and repair small amounts of damage as part of life and adaptation. The concern is balance: when the rate of damage repeatedly exceeds the tissue’s ability to repair and remodel, vulnerability to injury may increase before an obvious problem is visible.

This is also why ‘rest everything’ is not a complete training philosophy. Tissues need appropriate, progressive mechanical stimulus to adapt. The aim is not to remove load, but to apply a dose the horse can absorb.

Workload has several dimensions

Minutes ridden are a poor description of load on their own. Intensity, speed, number of jumping efforts, degree of collection, surface, gradients, turns, rider weight and skill, travel, previous work and recovery all change what those minutes mean.

A 30-minute session containing repeated high-effort work may be more demanding than a longer low-intensity hack. Similarly, deep going can increase muscular demand, whereas firm going changes impact and loading characteristics. Technical novelty adds coordination and mental demand even if the horse is not visibly out of breath.

The horse’s history matters equally. A workload can be modest for a well-conditioned horse and a spike for one returning from a break. Fitness is always specific to the task and to the individual who is being asked to perform it.

Train the whole horse

Progressive conditioning therefore needs continuity, variety and restraint. Sudden increases in speed, height, duration or frequency should be recognised as changes in load and budgeted for accordingly. Easier work and recovery are not interruptions to training, but rather part of the biological process through which training becomes capacity.

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Please note: No general article can prescribe a safe programme for an individual horse. Age, discipline, footing, health and previous conditioning matter too much, but one principle travels well across disciplines: the lungs may feel ready before every load-bearing tissue is ready.

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Key takeaway

Improved breathing and enthusiasm do not prove that bone, tendon, muscle and coordination have adapted equally. Fitness is task-specific and tissue-specific.