Skip to main content
Journal cover image

Hurry Up and Get Out of the Way! Exploring the Limits of Muscle-Based Latch Systems for Power Amplification.

Publication ,  Journal Article
Abbott, EM; Nezwek, T; Schmitt, D; Sawicki, GS
Published in: Integrative and comparative biology
December 2019

Animals can amplify the mechanical power output of their muscles as they jump to escape predators or strike to capture prey. One mechanism for amplification involves muscle-tendon unit (MT) systems in which a spring element (series elastic element [SEE]) is pre-stretched while held in place by a "latch" that prevents immediate transmission of muscle (or contractile element, CE) power to the load. In principle, this storage phase is followed by a triggered release of the latch, and elastic energy released from the SEE enables power amplification (PRATIO=PLOAD/PCE,max >1.0), whereby the peak power delivered from MT to the load exceeds the maximum power limit of the CE in isolation. Latches enable power amplification by increasing the muscle work generated during storage and reducing the duration over which that stored energy is released to power a movement. Previously described biological "latches" include: skeletal levers, anatomical triggers, accessory appendages, and even antagonist muscles. In fact, many species that rely on high-powered movements also have a large number of muscles arranged in antagonist pairs. Here, we examine whether a decaying antagonist force (e.g., from a muscle) could be useful as an active latch to achieve controlled energy transmission and modulate peak output power. We developed a computer model of a frog hindlimb driven by a compliant MT. We simulated MT power generated against an inertial load in the presence of an antagonist force "latch" (AFL) with relaxation time varying from very fast (10 ms) to very slow (1000 ms) to mirror physiological ranges of antagonist muscle. The fastest AFL produced power amplification (PRATIO=5.0) while the slowest AFL produced power attenuation (PRATIO=0.43). Notably, AFLs with relaxation times shorter than ∼300 ms also yielded greater power amplification (PRATIO>1.20) than the system driving the same inertial load using only an agonist MT without any AFL. Thus, animals that utilize a sufficiently fast relaxing AFL ought to be capable of achieving greater power output than systems confined to a single agonist MT tuned for maximum PRATIO against the same load.

Duke Scholars

Altmetric Attention Stats
Dimensions Citation Stats

Published In

Integrative and comparative biology

DOI

EISSN

1557-7023

ISSN

1540-7063

Publication Date

December 2019

Volume

59

Issue

6

Start / End Page

1546 / 1558

Related Subject Headings

  • Tendons
  • Muscle, Skeletal
  • Muscle Contraction
  • Movement
  • Models, Biological
  • Hindlimb
  • Evolutionary Biology
  • Biomechanical Phenomena
  • Anura
  • Animals
 

Citation

APA
Chicago
ICMJE
MLA
NLM
Abbott, E. M., Nezwek, T., Schmitt, D., & Sawicki, G. S. (2019). Hurry Up and Get Out of the Way! Exploring the Limits of Muscle-Based Latch Systems for Power Amplification. Integrative and Comparative Biology, 59(6), 1546–1558. https://doi.org/10.1093/icb/icz141
Abbott, Emily M., Teron Nezwek, Daniel Schmitt, and Gregory S. Sawicki. “Hurry Up and Get Out of the Way! Exploring the Limits of Muscle-Based Latch Systems for Power Amplification.Integrative and Comparative Biology 59, no. 6 (December 2019): 1546–58. https://doi.org/10.1093/icb/icz141.
Abbott EM, Nezwek T, Schmitt D, Sawicki GS. Hurry Up and Get Out of the Way! Exploring the Limits of Muscle-Based Latch Systems for Power Amplification. Integrative and comparative biology. 2019 Dec;59(6):1546–58.
Abbott, Emily M., et al. “Hurry Up and Get Out of the Way! Exploring the Limits of Muscle-Based Latch Systems for Power Amplification.Integrative and Comparative Biology, vol. 59, no. 6, Dec. 2019, pp. 1546–58. Epmc, doi:10.1093/icb/icz141.
Abbott EM, Nezwek T, Schmitt D, Sawicki GS. Hurry Up and Get Out of the Way! Exploring the Limits of Muscle-Based Latch Systems for Power Amplification. Integrative and comparative biology. 2019 Dec;59(6):1546–1558.
Journal cover image

Published In

Integrative and comparative biology

DOI

EISSN

1557-7023

ISSN

1540-7063

Publication Date

December 2019

Volume

59

Issue

6

Start / End Page

1546 / 1558

Related Subject Headings

  • Tendons
  • Muscle, Skeletal
  • Muscle Contraction
  • Movement
  • Models, Biological
  • Hindlimb
  • Evolutionary Biology
  • Biomechanical Phenomena
  • Anura
  • Animals