Fig 1.
The landing phase of a single-leg drop vertical jump.
A single-leg drop vertical jump on their dominant foot consisted of two stages: first, landing after dropping down from a 40 cm box; and second, landing after a maximal vertical jump rebounding from first drop.
Table 1.
Comparisons of the vGRF and lower extremity kinetics between the valgus and varus groups.
Fig 2.
The vGRF impulse of the knee valgus and varus groups.
This figure represents the means of the vGRF impulse and standard deviation of the knee valgus and varus groups during the deceleration phase of a single-leg drop vertical jump. These variables were normalized to the subject’s body weight (kg).
Fig 3.
Angular impulses in the lower extremity joints of the knee valgus and varus groups.
This figure represents the means of the hip, knee, and ankle angular impulses and standard deviations of the knee valgus and varus groups during the deceleration phase of a single-leg drop vertical jump. These variables were normalized to the product of the subject’s body weight (kg) and height (m). Asterisks indicate significant differences between the valgus and varus groups (*; p<0.01, **; p<0.05).
Fig 4.
Moments in the hip joint of the knee valgus and varus groups.
This figure represents the means of the hip extensor moment and standard deviations of the knee valgus (solid black lines) and knee varus groups (solid gray lines) during the landing phase. These variables were normalized to the product of the subject’s body weight (kg) and height (m). The vertical broken lines represent the end of the deceleration phase, which is defined as the period from the initial ground contact to the peak of vGRF in the valgus (black lines, 61.2 ± 9.32 ms) and varus groups (gray lines, 69.4 ± 19.4 ms). Variables were calculated by integrating the hip extensor moment—time curves during the deceleration phase, representing the hip extensor angular impulse.
Fig 5.
Moments in the knee joint of the knee valgus and varus groups.
This figure represents the means of the knee extensor moment and standard deviations of the knee valgus (solid black lines) and knee varus groups (solid gray lines) during the landing phase. These variables were normalized to the product of the subject’s body weight (kg) and height (m). The vertical broken lines represent the end of the deceleration phase, which is defined as the period from the initial ground contact to the peak of vGRF in the valgus (black lines, 61.2 ± 9.32 ms) and varus groups (gray lines, 69.4 ± 19.4 ms). Variables were calculated by integrating the knee extensor moment—time curves during the deceleration phase, representing the knee extensor impulse.
Fig 6.
Moments in the ankle joint of the knee valgus and varus groups.
This figure represents the means of the ankle plantar flexor moment and standard deviations of the knee valgus (solid black lines) and knee varus groups (solid gray lines) during the landing phase. These variables were normalized to the product of the subject’s body weight (kg) and height (m). The vertical broken lines represent the end of the deceleration phase, which is defined as the period from the initial ground contact to the peak of vGRF in the valgus (black lines, 61.2 ± 9.32 ms) and varus groups (gray lines, 69.4 ± 19.4 ms). Variables were calculated by integrating the ankle plantar flexor moment—time curves during the deceleration phase, representing the ankle plantar flexor angular impulses.
Table 2.
Comparisons of lower extremity kinematics between the valgus and varus groups.