The purpose of this study was to investigate the effects of surface slope and body posture (i.e., seated and standing) on lower extremity joint kinetics during cycling. Fourteen participants cycled at 250 watts power in three cycling conditions: level seated, uphill seated and uphill standing at a 14% slope. A motion analysis system and custom instrumented pedal were used to collect the data of fifteen consecutive cycles of kinematics and pedal reaction force. One crank cycle was equally divided into four phases (90° for each phase). A two-factor repeated measures MANOVA was used to examine the effects of the slope and posture on the selected variables. Results showed that both slope and posture influenced joint moments and mechanical work in the hip, knee and ankle joints (p < 0.05). Specifically, the relative contribution of the knee joint to the total mechanical work increased when the body posture changed from a seated position to a standing position. In conclusion, both surface slope and body posture significantly influenced the lower extremity joint kinetics during cycling. Besides the hip joint, the knee joint also played the role as the power source during uphill standing cycling in the early downstroke phase. Therefore, adopting a standing posture for more power output during uphill cycling is recommended, but not for long periods, in view of the risk of knee injury.

This study investigated ankle, knee, and hip joint movement coordination during brace use via a lower‐limb kinematic chain approach, which may influence biomechanical factors associated with injury risk. Twenty badminton players performed a left forecourt kick lunge under four brace conditions. Kinematic and kinetic data were collected using a motion capture system (Qualisys Arqus A12, 200 Hz) and force plates (Kistler 569×, 1000 Hz). A one‐way repeated‐measures ANOVA was applied for statistical analysis. At initial contact, elastic ankle brace use reduced ankle inversion angle ( p = 0.001) and knee varus angle ( p = 0.010) compared to the no‐brace condition. The use of a sleeve‐type knee brace increased knee varus angle ( p = 0.041) and knee varus moments ( p < 0.001), while decreasing hip eversion moments ( p = 0.006). Combined ankle and knee bracing increased knee varus angle ( p = 0.009). The use of elastic ankle and sleeve‐type knee braces was associated with condition‐dependent changes in stability and inter‐joint coordination due to the kinetic chain linking the hip, knee, and ankle. Protecting one joint may reflect compensatory adjustments in adjacent joints, which may have implications for brace selection. These findings should be interpreted cautiously in relation to injury prevention.