Introduction:
To assess the mode of sit-to-stand (STS) task performed in a habitual manner or with flexion or extension pattern transfer in asymptomatic young subjects. It was hypothesized that different initial movements of the lumbar-pelvic region would modify the performance of the STS task: coordination of STS in time and level of vertical ground reaction forces (VGRF).

Methods:
A convenience sample of 30 young asymptomatic volunteers, both genders, was recruited. The STS task was performed in a habitual manner or with a flexion or extension pattern. A Kistler platform was used to measure the VGRF and time of STS phases.

Results:
ANOVAs analysis revealed the main effect in the total time and in maximum VGRF during the STS manoeuvre in three STS tasks (F(2, 58) = 21.67–30.74; p < 0.00001). In the post-hoc analysis, there was no difference in the total time between flexion and extension pattern of STS (p > 0.05), there was no difference between the flexion and extension pattern in minimum VGRF (p > 0.05), but the latter task was the longest in preparation time (p < 0.001). The lowest maximum VGRF was bound with the extension pattern of STS (p < 0.01).

Conclusions:
The extension or flexion movement pattern modified STS performance and displayed different coordination in time and level of VGRF. Young asymptomatic participants performed the STS task longer with flexion or extension pattern than in the habitual pattern. The extension pattern of STS had the capacity to produce the lowest VGRF.