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The generation of centripetal force when walking in a circle: insight from the distribution of ground reaction forces recorded by plantar insoles.

Turcato AM, Godi M, Giordano A, Schieppati M, Nardone A - J Neuroeng Rehabil (2015)

Bottom Line: During curved walking, a greater loading of the lateral heel occurred for Foot-Out than Foot-In and LIN foot.On the contrary, a smaller lateral loading of the heel was found for Foot-In than LIN foot.At the metatarsal heads, an opposite behaviour was seen, since lateral loading decreased for Foot-Out and increased for Foot-In.

View Article: PubMed Central - PubMed

Affiliation: Posture and Movement Laboratory, Division of Physical Medicine and Rehabilitation, Scientific Institute of Veruno, Fondazione Salvatore Maugeri (IRCCS), Veruno, NO, Italy. turcato.anna@gmail.com.

ABSTRACT

Background: Turning involves complex reorientation of the body and is accompanied by asymmetric motion of the lower limbs. We investigated the distribution of the forces under the two feet, and its relation to the trajectory features and body medio-lateral displacement during curved walking.

Methods: Twenty-six healthy young participants walked under three different randomized conditions: in a straight line (LIN), in a circular clockwise path and in a circular counter-clockwise path. Both feet were instrumented with Pedar-X insoles. An accelerometer was fixed to the trunk to measure the medio-lateral inclination of the body. We analyzed walking speed, stance duration as a percent of gait cycle (%GC), the vertical component of the ground reaction force (vGRF) of both feet during the entire stance, and trunk inclination.

Results: Gait speed was faster during LIN than curved walking, but not affected by the direction of the curved trajectory. Trunk inclination was negligible during LIN, while the trunk was inclined toward the center of the path during curved trajectories. Stance duration of LIN foot and foot inside the curved trajectory (Foot-In) was longer than for foot outside the trajectory (Foot-Out). vGRF at heel strike was larger in LIN than in curved walking. At mid-stance, vGRF for both Foot-In and Foot-Out was higher than for LIN foot. At toe off, vGRF for both Foot-In and Foot-Out was lower than for LIN foot; in addition, Foot-In had lower vGRF than Foot-Out. During curved walking, a greater loading of the lateral heel occurred for Foot-Out than Foot-In and LIN foot. On the contrary, a smaller lateral loading of the heel was found for Foot-In than LIN foot. At the metatarsal heads, an opposite behaviour was seen, since lateral loading decreased for Foot-Out and increased for Foot-In.

Conclusions: The lower gait speed during curved walking is shaped by the control of trunk inclination and the production of asymmetric loading of heel and metatarsal heads, hence by the different contribution of the feet in producing the body inclination towards the centre of the trajectory.

No MeSH data available.


Related in: MedlinePlus

Dependence of the asymmetry index (AI) of the vGRF distribution at the metatarsal heads of the left and right foot (respectively, A and B) and at the heel of the left and right foot (respectively, C and D) on trunk inclination during linear (LIN), counter-clockwise (CCW) and clockwise (CW) trajectories. In the abscissa, larger negative values (average ± standard error, SE) of AI represent an increase in vGRF on the lateral part of the relevant foot region. In the ordinate, positive or negative values (average ± SE) represent respectively inclination towards right or left side. See text for explanation.
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Fig6: Dependence of the asymmetry index (AI) of the vGRF distribution at the metatarsal heads of the left and right foot (respectively, A and B) and at the heel of the left and right foot (respectively, C and D) on trunk inclination during linear (LIN), counter-clockwise (CCW) and clockwise (CW) trajectories. In the abscissa, larger negative values (average ± standard error, SE) of AI represent an increase in vGRF on the lateral part of the relevant foot region. In the ordinate, positive or negative values (average ± SE) represent respectively inclination towards right or left side. See text for explanation.

Mentions: As expected, the asymmetry index (AI) of the vGRF values of each foot exhibited a clear-cut dependence on trunk inclination during the CW and CCW trajectories. This dependence was opposite for the back (heel) and for the front part (metatarsal heads) of both feet. In Figure 6, the mean trunk inclination (right, positive values) is plotted against the mean AI (abscissa), for the LIN, CW and CCW trajectories. Briefly, during CW, the heel of the right foot (Foot-In, panel D) was loaded relatively more in its medial part, while during CCW, the heel of the same foot (now Foot-Out) was loaded more in its lateral part. A mirror pattern was observed for the front part of the right foot (panel B). In this case, during CW the metatarsal heads of the right foot (Foot-In) were loaded more in their lateral part, while during CCW the metatarsal heads of the right foot (now Foot-Out) were loaded more in their medial part (right bottom panel). Panels A and C show similar but opposite patterns for the left foot.Figure 6


The generation of centripetal force when walking in a circle: insight from the distribution of ground reaction forces recorded by plantar insoles.

Turcato AM, Godi M, Giordano A, Schieppati M, Nardone A - J Neuroeng Rehabil (2015)

Dependence of the asymmetry index (AI) of the vGRF distribution at the metatarsal heads of the left and right foot (respectively, A and B) and at the heel of the left and right foot (respectively, C and D) on trunk inclination during linear (LIN), counter-clockwise (CCW) and clockwise (CW) trajectories. In the abscissa, larger negative values (average ± standard error, SE) of AI represent an increase in vGRF on the lateral part of the relevant foot region. In the ordinate, positive or negative values (average ± SE) represent respectively inclination towards right or left side. See text for explanation.
© Copyright Policy - open-access
Related In: Results  -  Collection

License 1 - License 2
Show All Figures
getmorefigures.php?uid=PMC4325939&req=5

Fig6: Dependence of the asymmetry index (AI) of the vGRF distribution at the metatarsal heads of the left and right foot (respectively, A and B) and at the heel of the left and right foot (respectively, C and D) on trunk inclination during linear (LIN), counter-clockwise (CCW) and clockwise (CW) trajectories. In the abscissa, larger negative values (average ± standard error, SE) of AI represent an increase in vGRF on the lateral part of the relevant foot region. In the ordinate, positive or negative values (average ± SE) represent respectively inclination towards right or left side. See text for explanation.
Mentions: As expected, the asymmetry index (AI) of the vGRF values of each foot exhibited a clear-cut dependence on trunk inclination during the CW and CCW trajectories. This dependence was opposite for the back (heel) and for the front part (metatarsal heads) of both feet. In Figure 6, the mean trunk inclination (right, positive values) is plotted against the mean AI (abscissa), for the LIN, CW and CCW trajectories. Briefly, during CW, the heel of the right foot (Foot-In, panel D) was loaded relatively more in its medial part, while during CCW, the heel of the same foot (now Foot-Out) was loaded more in its lateral part. A mirror pattern was observed for the front part of the right foot (panel B). In this case, during CW the metatarsal heads of the right foot (Foot-In) were loaded more in their lateral part, while during CCW the metatarsal heads of the right foot (now Foot-Out) were loaded more in their medial part (right bottom panel). Panels A and C show similar but opposite patterns for the left foot.Figure 6

Bottom Line: During curved walking, a greater loading of the lateral heel occurred for Foot-Out than Foot-In and LIN foot.On the contrary, a smaller lateral loading of the heel was found for Foot-In than LIN foot.At the metatarsal heads, an opposite behaviour was seen, since lateral loading decreased for Foot-Out and increased for Foot-In.

View Article: PubMed Central - PubMed

Affiliation: Posture and Movement Laboratory, Division of Physical Medicine and Rehabilitation, Scientific Institute of Veruno, Fondazione Salvatore Maugeri (IRCCS), Veruno, NO, Italy. turcato.anna@gmail.com.

ABSTRACT

Background: Turning involves complex reorientation of the body and is accompanied by asymmetric motion of the lower limbs. We investigated the distribution of the forces under the two feet, and its relation to the trajectory features and body medio-lateral displacement during curved walking.

Methods: Twenty-six healthy young participants walked under three different randomized conditions: in a straight line (LIN), in a circular clockwise path and in a circular counter-clockwise path. Both feet were instrumented with Pedar-X insoles. An accelerometer was fixed to the trunk to measure the medio-lateral inclination of the body. We analyzed walking speed, stance duration as a percent of gait cycle (%GC), the vertical component of the ground reaction force (vGRF) of both feet during the entire stance, and trunk inclination.

Results: Gait speed was faster during LIN than curved walking, but not affected by the direction of the curved trajectory. Trunk inclination was negligible during LIN, while the trunk was inclined toward the center of the path during curved trajectories. Stance duration of LIN foot and foot inside the curved trajectory (Foot-In) was longer than for foot outside the trajectory (Foot-Out). vGRF at heel strike was larger in LIN than in curved walking. At mid-stance, vGRF for both Foot-In and Foot-Out was higher than for LIN foot. At toe off, vGRF for both Foot-In and Foot-Out was lower than for LIN foot; in addition, Foot-In had lower vGRF than Foot-Out. During curved walking, a greater loading of the lateral heel occurred for Foot-Out than Foot-In and LIN foot. On the contrary, a smaller lateral loading of the heel was found for Foot-In than LIN foot. At the metatarsal heads, an opposite behaviour was seen, since lateral loading decreased for Foot-Out and increased for Foot-In.

Conclusions: The lower gait speed during curved walking is shaped by the control of trunk inclination and the production of asymmetric loading of heel and metatarsal heads, hence by the different contribution of the feet in producing the body inclination towards the centre of the trajectory.

No MeSH data available.


Related in: MedlinePlus