While jumping is a fundamental movement skill and a key component in the development of specific sport skills, its coordination, especially at submaximal heights, has yet to be studied in detail. It is unknown if or how the intersegmental coordination patterns of the lower extremity change with increasing jump heights. Additionally, with recent work suggesting that jump research consider the take-off portion of a jump in phases (unweighting, eccentric, concentric), it is vital to understand if submaximal lower extremity coordination changes across these phases as well. The purpose of this study was to use modified vector coding to better characterize the intersegmental coordination relationships in the thigh-pelvis, shank-thigh, and foot-shank segment couples across different jump heights and phases of the countermovement jump.

Kinetic and kinematic data were collected from sixteen healthy participants as they performed eight countermovement jumps in each of four conditions:​ 25%, 50%, 75%, and 100% of their respective maximum jump heights. Coupling angles were calculated for the foot-shank, shank-thigh, and thigh-pelvis segment couples and were used to identify intersegmental coordination patterns using modified vector coding. One-way repeated measures ANOVAs assessed the within-participant differences of coordination pattern distribution frequency across jumps of varying heights. Participants were then divided into quartiles based on maximum jump height and student t-tests were used to see if within-participant trends in coordination differences extended to between-participants as well.

The results indicated that coordination patterns of the thigh-pelvis segment couple in the eccentric phase of the countermovement jump were most responsive to changes in within-participant jump height but no trends were seen in the between-participant analyses. This study provides more detailed descriptions of the intersegmental movements that define the production of countermovement jumps and the results can be used to better cue participants to perform submaximal and maximal jumps.