Comparison of Optimal Drop Heights in 2 Drop-Jump Exercises for Basketball Athletes With Differing Strength Levels.

Abstract

Purpose: Previous research has primarily focused on bounce drop jump (BDJ) rather than countermovement drop jump (CDJ) in studying optimal drop heights for drop jump. This study explored the biomechanic parameters of both BDJ and CDJ and their relationship with performance across varying drop heights based on the percentage of squat-jump height (SJH).

Methods: Twenty-four college basketball athletes were recruited and divided into low- and high-strength groups. Participants performed BDJ and CDJ at 50%, 75%, 100%, 125%, 150%, and 175% of SJH. The point or zone with the largest reactive strength index (RSI) corresponds to the optimal drop height for a drop jump.

Results: Optimal drop heights were determined to be 84.7% of SJH for BDJ low strength and 84.1% of SJH for BDJ high strength, with no significant difference between groups (P = .213). For CDJ, relative optimal drop heights were 104.6% of SJH for CDJ low strength and 106.1% of SJH for CDJ high strength, also with no significant difference (P = .717). Mechanical power with RSI exhibited a coefficient close to 1 (r = .98-.99), while average propulsive force demonstrated a very strong positive correlation with RSI (r = .72-.77).

Conclusions: It is recommended that basketball athletes incorporate particular percentages of SJH into drop jump, with 75% to 100% of SJH for BDJ and 100% to 125% of SJH for CDJ, as these heights are associated with achieving an optimal RSI and mechanical power. Tailoring the inclusion of BDJ or CDJ in training should account for the specific demands of on-court positions and task objectives for basketball players.