Standfase

Standfase, or the stance phase, is the portion of the gait cycle during which the foot is in contact with the ground. It begins with initial contact, when the foot first touches the ground, and ends with toe-off, when the foot leaves the ground. In normal walking at a comfortable speed, standfase accounts for about 60 percent of the gait cycle, while the remaining 40 percent is the swing phase, when the foot is off the ground.

The standfase can be subdivided into several sub-phases: initial contact, loading response, midstance, terminal stance, and preswing (toe-off). Each sub-phase serves characteristic mechanical roles. Initial contact and loading response absorb impact and help stabilize the leg and pelvis. Midstance aligns the body's center of mass over the supporting foot. Terminal stance prepares for propulsion, and preswing marks the transition to the next step as the body shifts weight forward and the opposite limb prepares to swing.

In running, the stance phase is typically shorter and is accompanied by a flight phase where both feet are off the ground at certain times. Overall stance duration decreases with increasing speed, and the pattern differs from walking due to changes in ground contact timing and propulsion strategies.

Standfase is a central focus in gait analysis, rehabilitation, and sports science. Variations in stance duration, double-support time, or symmetry can indicate clinical or functional issues, such as joint disease, muscle weakness, or neurological impairment. Assessments often use force measurements, motion capture, or wearable sensors to quantify stance characteristics and guide interventions.