Fig. 1

Ergospirometry parameters measured during HSET in early-training (week-4) and late-training (week-12) in 10 young two-year-old racing Thoroughbreds. Parameters include absolute peak aerobic capacity (V̇O₂pk, L/min), relative (to horse) peak aerobic capacity (V̇O₂pk, ml/kg H.min), total mass (horse and jockey) peak aerobic capacity (V̇O₂pk, ml/kg HJ.min), peak inspiratory flow (PkV̇_I, L/s), peak expiratory flow (PkV̇_E, L/s), peak inspiratory flow (PkV̇_E, L/s), respiratory frequency (Rf, bpm), minute ventilation (V̇E, L/min) and ventilation efficiency (V̇E/ V̇O₂pk). * Indicates a statistical difference (P < 0.05)