The purpose of this study was to identify the effect of additional load on lower limb joint work and joint work ratio between the braking and propulsion countermovement jump (CMJ) phase. Thirteen male sport students performed CMJ with five different loads up to 80% of body mass. Total joint work was significantly affected by the additional load and CMJ phase. A significant interaction effect of additional load and CMJ phase was found for ankle and knee joint work. Joint work ratio was significantly affected by load in the knee and hip joint. The braking proportion of the total joint work increased as additional load increased. The alterations in joint work and joint work ratio should be considered when prescribing loaded CMJ as training exercises in terms of changed training stimuli or interpreting performance parameters of CMJ with different load conditions
