Maintenance of approach velocity despite increasing internal load during repeated pole vault attempts.

Biomechanical analyses identify approach velocity-particularly in the final meters-as the primary mechanical determinant of vertical displacement in pole vault; yet how this velocity changes across repeated attempts performed below personal best height remains a practically important but largely untested question. As part of an applied field-based preparatory-phase protocol, we monitored the metabolic, cardiovascular, and perceptual responses of pole vaulters during four vault attempts performed 20 cm below their personal bests, and examined whether approach velocity was maintained in the final 5 m under these conditions. Eleven competitive pole vaulters (4 women, 7 men; age 20.3 ± 2.6 years) performed four consecutive vault attempts at heights 20 cm below their personal bests, with 3.5-4 min recovery intervals. Blood lactate (BL), heart rate (HR), and ratings of perceived exertion (RPE; Borg CR-10) were measured at predetermined time points throughout the protocol. Approach velocity and step kinematics (step length [SL], step frequency [SF], and contact time [CT]) over the final 5 m were derived from two-dimensional video analysis. Phase-related changes, load-velocity and step kinematic-velocity associations, subgroup interaction effects, and individual load change correlations were assessed using linear mixed-effects models (LMM) and Pearson correlation analyses. BL and HR showed no significant change between successive attempts (A