COP and foot function

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The trajectory of the centre of pressure during barefoot running as a potential measure for foot function.
De Cock A, Vanrenterghem J, Willems T, Witvrouw E, De Clercq D.
Gait Posture. 2007 Nov 8; [Epub ahead of print]

 

Sample entropy characteristics of movement for four foot types based on plantar centre of pressure during stance phase.
Mei Z, Zhao G, Ivanov K, Guo Y, Zhu Q, Zhou Y, Wang L.
Biomed Eng Online. 2013 Oct 10;12(1):101.

 

Influence of in-shoe heel lifts on plantar pressure and center of pressure in the medial–lateral direction during walking
Xianyi Zhang, Bo Li
Gait & Posture; Article in Press

 

Center of pressure trajectory during gait: A comparison of four foot positions
Vipul Lugade, Kenton Kaufman
Gait & Posture; Article in Press

 

Center of Pressure Trajectory during Gait: A Comparison of Four Foot Positions
Vipul Lugade, Kenton Kaufmanemail
Gait & Posture; Articles in Press

 

The article in post #5 in January appears to be the same as in post #6 this month. I wonder if they are delaying publishing because they got more intersting articles. I wonder what their initial hypothesis was. Oh really, the cop is more lateral when the foot is inverted. I guess sometimes you do need to document the obvious.

Eric

 

Estimation of Foot Plantar Center of Pressure Trajectories with Low-Cost Instrumented Insoles Using an Individual-Specific Nonlinear Model.
Hu X et al
Sensors (Basel). 2018 Feb 1;18(2). pii: E421. doi: 10.3390/s18020421.

 

Centre of pressure characteristics in normal, planus and cavus feet
Andrew K. BuldtEmail author, Saeed Forghany, Karl B. Landorf, George S. Murley, Pazit Levinger and Hylton B. Menz
Journal of Foot and Ankle Research201811:3

Conclusion
These findings indicate that there are differences in COP characteristics between foot postures, which may represent different mechanisms for generating force to facilitate forward progression of the body during the propulsive phases of gait.

 

The effect of center of pressure alteration on the ground reaction force during gait: a statistical model
Hadar Shaulian et al
Gait and Posture; Article in Press

 

DYNAMIC PATTERNS OF CENTER OF PRESSURE DURING WALKING IN DIFFERENT FOOT TYPES
JAE-HOON HEO, YURI KWON, HYEONG-MIN JEON, EUI-BUM CHOI and GWANG-MOON EOM
Journal of Mechanics in Medicine and Biology

 

A comparison of two techniques for center of pressure measurements
Jessica DeBerardinis et al
J Rehabil Assist Technol Eng. 2020 Jul 6

 

The impact of shod vs unshod walking on center of pressure variability
Zachary B Barrons, Gary D Heise
Gait Posture. 2020 Jun 26;81:116-119

 

Influence of the center of pressure on baropodometric gait pattern variations in the adult population with flatfoot: A case-control study
Luis Padrón et al
Front Bioeng Biotechnol. 2023 Mar 9

 

Effect of Sensor Size, Number and Position under the Foot to Measure the Center of Pressure (CoP) Displacement and Total Center of Pressure (CoPT) Using an Anatomical Foot Model
Hussein Abou Ghaida et al
Sensors (Basel). 2023 May 17;23(10):4848

 

Relationship Between Foot Kinematics and Center of Pressure Trajectory During Gait in Individuals with Flatfoot
Wataru Kawakami et al
J Am Podiatr Med Assoc. 2025 Jul-Aug;115(4):23-050.

 

These authors are still embracing the Biomechanical Postural Model, which my research has demonstrated to be incomplete.

Approximately 15 years ago, I introduced/refined the Foot Neurophysiological Postural Model, which is a more complete and accurate postural model.

However, I do agree with their conclusion that foot eversion needs to be controlled.

 

So you have a " Foot Neurological Postural Model" that doesn't involve the muscles of the foot. Is that correct?

 

Not exactly.

According to the Foot Neurophysiological Postural Model, the foot’s Intrinsic muscles do not encode the Foot’s Sensory Feedback to the cerebellum. This is done via the Meissner and Merkel mechanosensory receptors.

Whether the cerebellum recruits the foot's intrinsic muscles to adjust posture requires clarification.

 

Then the best available research says your model is pretty much wrong, or at best incomplete.

We know the vestibular apparatus evokes intrinsic foot muscle activity which contributes to balance and posture. Does the vestibular apparatus have any role to play in your postural model or do you regard it as irrelevant to balance ?

 

I am not sure where you came up with that conclusion. The FnPPM is the most complete model, to date, to explain how the foot programs the brain.

How the cerebellum uses muscles to adjust posture is another issue. To date, there has been no definitive research published to explain, in detail, how this occurs.

The brainstem receives postural sensory information from the foot, the teeth, and the inner ear. IMO, based on the research done at the International Academy RPT, the foot is the major player in postural control. Other researchers may not agree, but posterity will determine who is correct

 

What programming Brian ? According to you your insoles bring about immediate postural correction . Removal, immediate relapse . That's not changing programming.

How do afferents from a small area of the foot affect muscles to bring about changes in global posture? You apparently have no idea. So how do you know the intrinsic muscles aren't amongst those primarily involved .

IARPT ( your house?) . Major player in what sense ? Sensory ? Just cutaneous nerve endings .

 

Proprioceptive insoles do not adjust posture. The cerebellum adjusts posture. Capire?

Proprioceptive insoles are used to reprogram the cerebellum.
I explain how this occurs in detail in my EU DC courses, which go online in January 2026.

Have you read my research papers on the Foot Neurophysiological Postural Model?
I encourage you to read the papers below (if you haven't already done so) and then ask questions.

• Biomechanical Postural Model vs Neurophysiological Postural Model
• PreClinical Clubfoot Deformity: Neurophysiological Postural Model

 

Please read what's written.

I you don't want to answer questions, don't post.

 

The intrinsic foot muscles are known to help control balance and posture. It's part of what they do.

Luke kelly et al 2012 "Recruitment of the intrinsic foot muscles with increasing postural demand"

"Interpretations

Activation of the plantar intrinsic foot muscles increases with increasing postural demand. These muscles are clearly important in postural control and are recruited in a highly co-ordinated manner to stabilise the foot and maintain balance in the medio-lateral direction, particularly during single leg stance."

IMO, not everything you have to say is wrong and too little emphasis is placed on neuromuscular aspects of the foot. I believe you may prefer the term neurophysiological to neuromuscular because you want to avoid talking about muscles. The brain does not produce force, the muscles do.

The brain controls posture and balance . Sensory information comes from sources such as the foot, vestibular apparatus and the eyes. Efferents from the brain control the muscles. A postural model that simply says cutaneous afferents( signals) to brain stem , hey presto ,balance, is clearly utterly inadequate.

 

The intrinsic muscles do not program the Foot Sensory Feedback to the cerebellum. Kelly 2012 does not state otherwise. He simply states muscles are recruited to maintain postural stability. And I totally agree.

Again, and I have said this many times, posterity will prove or disprove my postural model.

 

What do you mean ? If you are trying to say that the muscle spindles in the intrinsic foot muscles do not send information to the brain about centre of pressure movements, that is clearly wrong. Look at the figure immediately below from Knellwolf et al 2025. It shows that signals from the intrinsic spindles " can faithfully encode changes in CoP during spontaneous or evoked postural sway, a function shared by slowly adapting type II afferents in the sole" .




Note that only one type of cutaneous receptor provides information as accurately as the muscle spindles. Knellwolf and his colleagues, who do not have a prejudice with regard to the whether or not the intrinsic foot muscles have a greater role to play in control of posture do have this to say .

"Moreover, selective anaesthesia of cutaneous afferents of the sole of the foot increases postural sway by only ∼11% (Meyer et al., 2004), whereas increases of ∼40%–60% occur in diabetic neuropathy, in which both muscle and cutaneous afferents are affected (Boucher et al., 1995; Simoneau et al., 1994). Accordingly, it is likely that muscle afferents from the foot contribute more to the control of postural sway than do cutaneous afferents, but in the absence of direct data this is speculation."

As far as I can see you don't have a postural model beyond - signals from cutaneous nerve endings ( no particular type specified) to brain results in efferents giving balance.
Hopeless.

 

In older adults, most falls occur during simple weight shifting ,for example going from sitting to standing, be that from a chair, toilet seat, or whatever.

The paper linked to below demonstrates that strengthening the foot via the short foot exercises is effective in improving dynamic balance during this manoeuvre even in healthy young adults ( they generally stronger feet than older people).


Differences in Calf-Raise Exercise and Short-Foot Exercise on Feedforward and Feedback Activation in Healthy Young

Author links open overlay panelJinyuan Guo 1,
https://doi.org/10.1016/j.ptsp.2025.11.004Get rights and content
Highlights

• •
  Both short-foot and calf-raise exercise improve dynamic balance and enhance neuromuscular response efficiency by strengthening both feedforward and feedback control mechanisms in healthy young adults.
• •
  Compared to the calf-raise exercise group, the short-foot exercise group exhibited more pronounced and sustained improvements in center-of-gravity transfer during sit-to-stand transitions and in Adaptation Test results.
• •
  These findings suggest that targeted muscle training confers specific benefits for postural control, reinforcing the importance of muscle-specific interventions in optimizing balance rehabilitation and improving athletic performance.