The stability of the deadlift three repetition maximum

This study investigated the stability of three repetition maximum (3RM) strength during the deadlift. Eleven participants performed four testing sessions comprising a one repetition maximum test and 3RM tests separated by 48 h. Preparedness was assessed before each testing session using countermovement jumps and by measuring barbell velocity during each set of deadlifts. Trivial statistically significant differences were determined for the 3RM between T1 and both T2 (p = 0.012; ES [95% CI] = -0.1 [-0.58, 0.41]) and T3 (p = 0.027; ES [95% CI] = -0.09 [-0.57, -0.43]). No significant differences were noted between T2 and T3 (p = 0.595; ES [95% CI] = 0.01 [-0.49, 0.50]). No significant differences in jump height (p = 0.071), time-to-take-off (p = 0.862), eccentric displacement (p = 0.209), or mean force during any countermovement jump sub-phase were found between each session (p = 0.529-0.913). Small differences in barbell mean velocity were found between both T1-T2 (effect size statistics (ES) = -0.21-0.27) and T2-T3 (ES = 0.31-0.48), while trivial differences were found at others. Therefore, 3RM deadlift strength appears stable enough over a microcycle to continue using traditionally recommended heavy/light programming strategies.