Frequency-domain patterns in foot-force line-of-action: an emergent property of standing balance control.

A recent line of work suggests that the net behavior of the foot-ground interaction force provides insight into quiet-standing-balance dynamics and control. Through human-subject experiments, Boehm et al. found that the relative variations of the center of pressure and force orientation emerge as a distinct pattern in the frequency domain, termed the "intersection-point (IP) height.

Human foot force suggests different balance control between younger and older adults.

Aging can cause the decline of balance ability, which can lead to increased falls and decreased mobility. This work aimed to discern differences in balance control between healthy older and younger adults. Foot force data of 38 older and 65 younger participants (older and younger than 60 yr, respectively) were analyzed.

Reliability and validity of the force intersection point in the assessment of human quiet standing balance.

Background: This study evaluated psychometric properties of the Intersection Point Height, derived from ground-on-feet force characteristics, as a tool for assessing balance control. We compare this metric with traditional center of pressure (CP) measurements.

Methods: Data from a public dataset of 146 participants, divided into younger (<60 years old) and older (≥60 years old) adults, were analyzed.

Frequency-dependent behavior of paretic and non-paretic leg force during standing post stroke.

Maintaining upright posture in quiet standing is an important skill that is often disrupted by stroke. Despite extensive study of human standing, current understanding is incomplete regarding the muscle coordination strategies that produce the ground-on-foot force (F) that regulates translational and rotational accelerations of the body. Even less is understood about how stroke disrupts that coordination.

Modulation of sagittal-plane center of pressure and force vector direction in human standing on sloped surfaces.

The multi-joint coordination responsible for maintaining upright posture in the standing human manifests in the pattern of variation of the support-surface force (F). Assessment of both the translational and rotational kinematics in the sagittal-plane requires understanding the critical relationship between the direction and location of F. Prior work demonstrated that band-pass filtered F direction and center-of-pressure (CoP) covary in time such that the F vector lines-of-action pass near a fixed point called an intersection point (IP).