Performance and Physiologic Responses to Repeated 3-Minute All-Out Shuttle Tests

Mendelson, BJ, Ebersole, KT, Brau, SD, and Ebersole, NT. Performance and physiologic responses to repeated 3-minute all-out shuttle tests. J Strength Cond Res 39(9): e1059-e1066, 2025-The purpose of this investigation was to examine changes in performance capacity in repeated all-out efforts. Ten participants (24.00 ± 4.32 years, 79.71 ± 46.05 kg, 1.79 ± 0.102 m) completed a maximal treadmill test with direct breath-by-breath and heart rate (HR) analysis to capture maximal aerobic capacity (V̇ o2 peak, mL·kg -1 ·minute -1 ) and HR (HR PEAK-TM , bpm). Participants also completed three 30-meter shuttle sprint 3-minutes all-out test (3 MT) bouts, from which critical velocity (CV, m·second -1 ), anaerobic work capacity ( D', m), maximal sprint speed (S MAX , m·second -1 ), and the difference between S MAX and CV (S MAX-CV , m·second -1 ) were calculated. The 30-second end-3MT average HR (HR END-3MT , bpm), pretest blood lactate (LA -PRE , mmol·L -1 ), and post-test blood lactate (LA -POST , mmol·L -1 ) captured physiologic responses to the 3 MT session. Repeated measures ANOVAs (⍺ = 0.05) indicated that CV ( F = 1.401, p = 0.270) did not significantly change across bouts, but D' ( F = 7.271, p = 0.005) and S MAX ( F = 7.474, p = 0.004) significantly decreased across bouts. HR END-3MT was significantly lower than HR PEAK-TM ( F = 11.961, p < 0.001), and the LA -POST did not significantly change across bouts ( p > 0.05). Correlation analysis indicated that V̇ o2 peak was significantly related to CV in bout 1 ( r = 0.745, p = 0.013) and bout 3 ( r = 0.746, p = 0.013). CV may be a repeatable level of performance but the ability to work more than the CV is significantly diminished in repeated all-out efforts. Further research is needed to examine methods to improve repeatability of D' .