Adaptation of osteochondral tissues is based on strains experienced during exercise at each location within the joint. Different exercise intensities and types may induce particular site-specific strains, influencing osteochondral adaptation, potentially predisposing to injury. Hypotheses: Patterns of equine distal tarsal subchondral bone (SCB) thickness relate to type and intensity of exercise; high intensity exercise leads to site-specific increases thickness increases. Methods: SCB was measured at defined dorsal and plantar locations on magnetic resonance images of cadaver tarsi collected from horses with a history of low (general purpose [n=20], horse walker [n=6]) or high (elite competition [n=12], race training [n=15], treadmill training [n=4]) exercise intensity. SCB thickness was compared between sites within each exercise group, and between exercise groups. Results: SCB thickness in elite competition and race training, but not treadmill training, was greater than low intensity exercise. For general purpose, lateral SCB thickness was greater than medial throughout. Horse walker exercise led to relatively thicker lateral and medial SCB compared with the midline. Elite competition was associated with increased SCB thickness proximal medial and distal lateral. For race training and treadmill training, minimal differences arose between sites overall, although the lateral aspect was greater than medial and medial than midline at a few race training sites. Conclusions: Different types of high intensity exercise were associated with different patterns of SCB thickness across the joints, from medial to lateral, and proximal to distal, indicating that exercise intensity and type of exercise affect SCB response at any particular site within a joint.