Journal of Bionic Engineering

, Volume 5, Issue 3, pp 175–180 | Cite as

A Phase-Dependent Hypothesis for Locomotor Functions of Human Foot Complex

  • Lei RenEmail author
  • David Howard
  • Lu-quan Ren
  • Chris Nester
  • Li-mei Tian


The human foot is a very complex structure comprising numerous bones, muscles, ligaments and synovial joints. As the only component in contact with the ground, the foot complex delivers a variety of biomechanical functions during human locomotion, e.g. body support and propulsion, stability maintenance and impact absorption. These need the human foot to be rigid and damped to transmit ground reaction forces to the upper body and maintain body stability, and also to be compliant and resilient to moderate risky impacts and save energy. How does the human foot achieve these apparent conflicting functions? In this study, we propose a phase-dependent hypothesis for the overall locomotor functions of the human foot complex based on in-vivo measurements of human natural gait and simulation results of a mathematical foot model. We propse that foot functions are highly dependent on gait phase, which is a major characteristics of human locomotion. In early stance just after heel strike, the foot mainly works as a shock absorber by moderating high impacts using the viscouselastic heel pad in both vertical and horizontal directions. In mid-stance phase (~80% of stance phase), the foot complex can be considered as a springy rocker, reserving external mechanical work using the foot arch whilst moving ground contact point forward along a curved path to maintain body stability. In late stance after heel off, the foot complex mainly serves as a force modulator like a gear box, modulating effective mechanical advantages of ankle plantiflexor muscles using metatarsal-phalangeal joints. A sound understanding of how diverse functions are implemented in a simple foot segment during human locomotion might be useful to gain insight into the overall foot locomotor functions and hence to facilitate clinical diagnosis, rehabilitation product design and humanoid robot development.


biomechanics human foot locomotion rollover model shock absorber spring phase-dependent 


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.


  1. [1]
    Hicks J H. The mechanics of the foot. I. The joints. Journal of Anatomy, 1953, 87, 345–357.Google Scholar
  2. [2]
    Hicks J H. The mechanics of the foot. II. The plantar aponeurosis and the arch. Journal of Anatomy, 1954, 88, 25–30.Google Scholar
  3. [3]
    Whittle M W. Generation and attenuation of transient impulsive forces beneath the foot: A review. Gait and Posture, 1999, 10, 264–275.CrossRefGoogle Scholar
  4. [4]
    Carrier D R, Heglund N C, Earls K D. Variable gearing during locomotion in the human musculoskeletal system. Science, 1994, 265, 651–653.CrossRefGoogle Scholar
  5. [5]
    Erdemir A, Piazza S J. Rotational foot placement specifies the lever arm of the ground reaction force during the push-off phase of walking initiation. Gait and Posture, 2002, 15, 212–219.CrossRefGoogle Scholar
  6. [6]
    Carson M C, Harrington M E, Thompson N, O’Connor J J, Theologis T N. Kinematic analysis of a multi-segment foot model for research and clinical applications: A repeatability analysis. Journal of Biomechanics, 2001, 34, 1299–1307.CrossRefGoogle Scholar
  7. [7]
    De Clercq D, Aerts P, Kunnen M. The mechanical characteristics of the human heel pad during foot strike in running: An in vivo cineradiographic study. Journal of Biomechanics, 1994, 27, 1213–1222.CrossRefGoogle Scholar
  8. [8]
    Gefen A, Megido-Ravid M, Itzchak Y, Arcan M. Biomechanical analysis of the three-dimensional foot structure during gait: A basic tool for clinical applications. Journal of Biomechanical Engineering, 2000, 122, 630–639.CrossRefGoogle Scholar
  9. [9]
    Nagatsu M, Kubota S, Aoki M, Tsukishima T, Arimoto H, Sato K, Gilchrist L A, Winter D A. A two-part, viscoelastic foot model for use in gait simulations. Journal of Biomechanics, 1996, 29, 795–798.CrossRefGoogle Scholar
  10. [10]
    Jenkyn T R, Nicol A C. A multi-segment kinematic model of the foot with a novel definition of forefoot motion for use in clinical gait analysis during walking. Journal of Biomechanics, 2007, 40, 3271–3278.CrossRefGoogle Scholar
  11. [11]
    Ker R F, Bennett M B, Bibby S R, Kester R C, Alexander R M. The spring in the arch of the human foot. Nature, 1987, 325, 147–149.CrossRefGoogle Scholar
  12. [12]
    Nester C J, Liu A M, Ward E, Howard D, Cocheba J, Derrick T, Paterson P. In vitro study of foot kinematics using a dynamic walking cadaver model. Journal of Biomechanics, 2007, 40, 1927–1937.CrossRefGoogle Scholar
  13. [13]
    Scott S H, Winter D A. Biomechanical model of the human foot: Kinematics and kinetics during the stance phase of walking. Journal of Biomechanics, 1993, 26, 1091–1104.CrossRefGoogle Scholar
  14. [14]
    Ren L, Howard D, Ren L Q, Tian L M, Nester C J. A generic analytical foot rollover model for predicting translational ankle kinematics in gait simulation studies. Journal of Biomechanics, in review.Google Scholar
  15. [15]
    Winter D A, Sidwall H G, Hobson D A. Measurement and reduction of noise in kinematics of locomotion. Journal of Biomechanics, 1974, 7, 157–159.CrossRefGoogle Scholar
  16. [16]
    Pezzack J C, Norman R W, Winter D A. An assessment of derivative determining techniques used for motion analysis. Journal of Biomechanics, 1977, 10, 377–382.CrossRefGoogle Scholar
  17. [17]
    Hansen A H, Childress D S, Knox E H. Roll-over shapes of human locomotor systems: Effects of walking speed. Clinical Biomechanics, 2004, 19, 407–414.CrossRefGoogle Scholar
  18. [18]
    Gefen A, Megido-Ravid M, Itzchak Y. In vivo biomechanical behavior of the human heel pad during the stance phase of gait. Journal of Biomechanics, 2001, 34, 1661–1665.CrossRefGoogle Scholar
  19. [19]
    Ker R F. The time-dependent mechanical properties of the human heel pad in the context of locomotion. Journal of Experimental Biology, 1996, 199, 1501–1508.Google Scholar
  20. [20]
    Cavagna G A, Heglund N C, Taylor C R. Mechanical work in terrestrial locomotion: Two basic mechanisms for minimizing energy expenditure. American Journal of Physiology, 1977, 233, R243–R261.Google Scholar
  21. [21]
    Donelan J M, Kram R, Kuo A D. Simultaneous positive and negative external mechanical work in human walking. Journal of Biomechanics, 2002, 35, 117–124.CrossRefGoogle Scholar
  22. [22]
    Adamczyk P G, Collins S H, Kuo A D. The advantages of a rolling foot in human walking. Journal of Experimental Biology, 2006, 209, 3953–3963.CrossRefGoogle Scholar
  23. [23]
    McGeer T. Passive dynamic walking. International Journal of Robotics Research, 1990, 9, 62–82.CrossRefGoogle Scholar
  24. [24]
    Ren L, Jones R K, Howard D. Predictive modelling of human walking over a complete gait cycle. Journal of Biomechanics, 2007, 40, 1567–1574.CrossRefGoogle Scholar

Copyright information

© Jilin University 2008

Authors and Affiliations

  • Lei Ren
    • 1
    Email author
  • David Howard
    • 2
  • Lu-quan Ren
    • 3
  • Chris Nester
    • 2
  • Li-mei Tian
    • 3
  1. 1.School of Physical Science and Engineering, King’s College of LondonUniversity of LondonLondonUK
  2. 2.Centre for Rehabilitation and Human Performance ResearchUniversity of SalfordSalfordUK
  3. 3.Key Laboratory for Terrain-Machine Bionics EngineeringJilin UniversityChangchunP. R. China

Personalised recommendations