Intrinsic foot muscles contribute to elastic energy storage and return in the human foot
| Autor: | Andrew G. Cresswell, Dominic James Farris, Glen A. Lichtwark, Luke A. Kelly |
|---|---|
| Rok vydání: | 2019 |
| Předmět: |
Adult
Male Muscle fascicle medicine.medical_specialty Physiology STRIDE 030204 cardiovascular system & hematology Biology Young Adult 03 medical and health sciences 0302 clinical medicine Physical medicine and rehabilitation Foot Joints Physiology (medical) medicine Foot muscles Humans Muscle Skeletal Mechanical energy Foot Elastic energy 030229 sport sciences Healthy Volunteers Biomechanical Phenomena medicine.anatomical_structure Female Ankle Joint Foot (unit) |
| Zdroj: | Journal of Applied Physiology. 126:231-238 |
| ISSN: | 1522-1601 8750-7587 |
| DOI: | 10.1152/japplphysiol.00736.2018 |
| Popis: | The human foot is uniquely stiff to enable forward propulsion, yet also possesses sufficient elasticity to act as an energy store, recycling mechanical energy during locomotion. Historically, this dichotomous function has been attributed to the passive contribution of the plantar aponeurosis. However, recent evidence highlights the potential for muscles to modulate the energetic function of the foot actively. Here, we test the hypothesis that the central nervous system can actively control the foot’s energetic function, via activation of the muscles within the foot’s longitudinal arch. We used a custom-built loading apparatus to deliver cyclical loads to human feet in vivo, to deform the arch in a manner similar to that observed in locomotion. We recorded foot motion and forces, alongside muscle activation and ultrasound images from flexor digitorum brevis (FDB), an intrinsic foot muscle that spans the arch. When active, the FDB muscle fascicles contracted in an isometric manner, facilitating elastic energy storage in the tendon, in addition to the energy stored within the plantar aponeurosis. We propose that the human foot is akin to an active suspension system for the human body, with mechanical and energetic properties that can be actively controlled by the central nervous system. NEW & NOTEWORTHY The human foot is renowned for its ability to recycle mechanical energy during locomotion, contributing up to 17% of the energy required to power a stride. This mechanism has long been considered passive in nature, facilitated by the elastic ligaments within the arch of the foot. In this paper, we present the first direct evidence that the intrinsic foot muscles also contribute to elastic energy storage and return within the human foot. Isometric contraction of the flexor digitorum brevis muscle tissue facilitates tendon stretch and recoil during controlled loading of the foot. The significance of these muscles has been greatly debated by evolutionary biologists seeking to understand the origins of upright posture and gait, as well as applied and clinical scientists. The data we present here show a potential function for these muscles in contributing to the energetic function of the human foot. |
| Databáze: | OpenAIRE |
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