Review
Physiology
Andre Tomalka
Summary: Eccentric muscle loading has unique features including increased force, work, and performance while consuming less oxygen, reduced metabolic cost, and decreased muscle activity. This review summarizes approaches to explain muscular contraction dynamics and molecular and cellular mechanisms underlying eccentric muscle loading. It emphasizes the functional link between sarcomeric components, particularly the essential role of titin in skeletal muscle. The interaction between titin and actin can explain linear force increases in active lengthening experiments. This review aims to contribute to a detailed understanding of muscle behavior, force generation, and disease.
PFLUGERS ARCHIV-EUROPEAN JOURNAL OF PHYSIOLOGY
(2023)
Article
Biophysics
Atsuki Fukutani, Walter Herzog
Summary: The study aimed to examine the magnitude of the stretch-shortening cycle (SSC) effect in inhibited skeletal muscle force states. Results indicated that the SSC effect was preserved in the reduced force state and was significantly greater compared to the normal force state.
JOURNAL OF BIOMECHANICS
(2021)
Article
Biology
Shuyue Liu, Venus Joumaa, Walter Herzog
Summary: The steady-state isometric force of a muscle after active stretching is greater than that of a purely isometric contraction at the same length and activation level, a phenomenon known as residual force enhancement (rFE). The role of cross-bridge cycling in rFE was investigated, and it was found that fast stretching, which causes cross-bridge slipping, is associated with a loss of rFE.
JOURNAL OF EXPERIMENTAL BIOLOGY
(2022)
Article
Biology
Cameron Hill, Elisabetta Brunello, Luca Fusi, Jesus G. Ovejero, Malcolm Irving
Summary: The study revealed a sequence of structural changes during muscle activation, including thin filament activation, disruption of the helical array of myosin motors, release of myosin motor domains from the folded conformation, and actin attachment. Physiological force generation in skeletal muscle twitch response is limited by incomplete activation of the thick filament and rapid inactivation of both filaments.
Article
Multidisciplinary Sciences
Siwoo Jeong, Kiisa Nishikawa
Summary: In this study, the mechanisms of residual force depression were investigated by examining the stiffness to force ratio during force redevelopment after shortening at different velocities. The results showed that the relationship between muscle stiffness and force changed with decreasing shortening velocity. Weakly-bound cross bridges and a tunable elastic element like titin were proposed as potential explanations for these findings.
SCIENTIFIC REPORTS
(2023)
Article
Biophysics
Shuyue Liu, Heron Baptista de Oliveira Medeiros, Heiliane de Brito Fontana, Walter Herzog
Summary: Passive force enhancement refers to the increase in force generated during passive stretching of a muscle after it has been actively stretched. The mechanism behind this enhancement is still unclear, but it is believed to be related to the stability of sarcomeres and protection against over-stretching. A hypothesis that passive force enhancement is abolished when the actively stretched muscle is deactivated and passively shortened was rejected in experiments with rabbit psoas fibers. Instead, it was found that passive force enhancement increased when the fibers were shortened and then stretched again, and this increase was time-dependent. These findings suggest that titin, a protein involved in muscle contraction, may play a role in passive force enhancement. Molecular level experiments are needed to test this hypothesis.
JOURNAL OF BIOMECHANICS
(2022)
Article
Multidisciplinary Sciences
Thomas Kampourakis, Malcolm Irving
Summary: The authors propose that sequential folding of myosin motors onto the filament backbone may be responsible for shortening-induced de-activation in the heart, which is essential for the efficient function of the heart. The Frank-Starling relation, where increased venous filling triggers a stronger contraction in the next beat, also plays a crucial role in the normal function of heart muscle.
NATURE COMMUNICATIONS
(2021)
Review
Physiology
Atsuki Fukutani, Tadao Isaka, Walter Herzog
Summary: The stretch-shortening cycle (SSC) effect in skeletal muscle is characterized by transient enhancement of force during concentric contraction following eccentric contraction. Proposed mechanisms for this effect include stretch-reflex activation, energy storage in tendons, pre-activation, cross-bridge kinetics, and residual force enhancement. Studies suggest that factors other than stretch-reflex activation and tendon energy storage contribute to the SSC effect, with varying degrees of contribution depending on contractile conditions. Further research is needed to explore alternative mechanisms and unresolved issues in this field.
FRONTIERS IN PHYSIOLOGY
(2021)
Article
Sport Sciences
Cassio V. Ruas, Christopher Latella, Janet L. Taylor, G. Gregory Haff, Kazunori Nosaka
Summary: This study investigated the effects of concentric and eccentric contractions on neuromuscular fatigue and muscle damage, and found that coupled concentric and eccentric contractions did not exacerbate these issues, despite performing twice the number of contractions compared to eccentric-only contractions.
MEDICINE & SCIENCE IN SPORTS & EXERCISE
(2022)
Article
Physiology
Jiayu Shi, Masanobu Wada
Summary: The study aimed to investigate the effects of eccentric contraction on force enhancement in rat fast-twitch skeletal muscle. It was found that eccentric contraction did not affect the amount of degraded titin, but significantly decreased isometric torques in the muscle. However, it increased passive torque and passive force in skinned fibers. The results suggest that eccentric contraction can attenuate force reductions and enhance passive force in skeletal muscle.
PHYSIOLOGICAL REPORTS
(2023)
Article
Biology
Atsuki Fukutani, Shiho Kunimatsu, Tadao Isaka
Summary: The study investigated the impact of 2,3-butanedione monoxime-induced force loss on isometric and eccentric forces, revealing a significant increase in force loss during the pre-stretch phase and a more pronounced mitigated force loss during the eccentric contraction in the long condition.
JOURNAL OF EXPERIMENTAL BIOLOGY
(2022)
Article
Physiology
Ole Emil Andersen, Anders M. Kristensen, Ole B. Nielsen, Kristian Overgaard
Summary: This study aimed to investigate the acute effects of muscle activity on eccentric force of slow and fast-twitch muscles and its relation to postactivation potentiation. The results showed that muscle force consistently increased during consecutive contractions while isometric peak force slightly declined. This increase in eccentric force may be important for sports performance.
JOURNAL OF APPLIED PHYSIOLOGY
(2023)
Article
Multidisciplinary Sciences
Martin Groeber, Savvas Stafilidis, Arnold Baca
Summary: Stretch-induced residual force enhancement (rFE) is associated with increased performance in a stretch-shortening cycle (SSC), particularly important for movements at greater muscle-tendon unit lengths.
SCIENTIFIC REPORTS
(2021)
Article
Physiology
Yuki Ashida, Koichi Himori, Katsuyuki Tamai, Iori Kimura, Takashi Yamada
Summary: Preconditioning contractions (PCs) improve recovery from eccentric contractions (ECCs) by inhibiting the loss of STAC3 and preventing Ca2+-dependent proteolysis, highlighting the role of STAC3 in the protective effects of PCs against damaging ECCs.
JOURNAL OF APPLIED PHYSIOLOGY
(2021)
Article
Physiology
Venus Joumaa, Atsuki Fukutani, Walter Herzog
Summary: The study aimed to investigate the impact of the stretch-shortening cycle (SSC) on muscle energy cost, and the results showed that the increase in total force following SSCs was achieved by increasing the proportion of attached cross-bridges and titin stiffness, while ATP consumption per unit of force remained the same.
FRONTIERS IN PHYSIOLOGY
(2021)
Article
Orthopedics
Jaqueline Lourdes Rios, David A. Hart, Raylene A. Reimer, Walter Herzog
Summary: The study found that aerobic exercise or prebiotic fiber supplementation, either alone or in combination, improved certain markers of metabolic disturbance but did not have a significant impact on knee joint damage. It is important to note that chow-fed rats showed similar knee osteoarthritis-like damage as the high-fat/high-sucrose-fed rats.
Review
Clinical Neurology
Jason J. Howard, Walter Herzog
Summary: Recent research has shed light on the pathophysiological mechanisms of muscle contractures in cerebral palsy, involving upregulation of collagen content and excessive length of sarcomeres. The use of botulinum toxin for spasticity management may lead to increased muscle atrophy and fibrofatty content. Emerging theories in areas such as muscle homeostasis and epigenetic mechanisms are contributing to a deeper understanding of this complex issue.
FRONTIERS IN NEUROLOGY
(2021)
Article
Anatomy & Morphology
Santeri J. O. Rytky, Lingwei Huang, Petri Tanska, Aleksei Tiulpin, Egor Panfilov, Walter Herzog, Rami K. Korhonen, Simo Saarakkala, Mikko A. J. Finnila
Summary: The study utilized deep learning segmentation for mu CT images to assess 3D CC morphology. Analysis of samples from different anatomical regions revealed variation in CC thickness, with the thickest in the patella and thinnest in the tibial plateau. The proposed mu CT analysis provides a reliable method for ex vivo 3D assessment of CC morphology, with potential applications in understanding cartilage mineralization dynamics and joint diseases.
JOURNAL OF ANATOMY
(2021)
Article
Engineering, Biomedical
Scott C. Sibole, Eng Kuan Moo, Salvatore Federico, Walter Herzog
Summary: PCM asymmetry may play an important role in cartilage development, pathology, and engineering. The changes in PCM geometry can affect the cellular mechanical environment and the surface strains on cells.
ANNALS OF BIOMEDICAL ENGINEERING
(2022)
Article
Biophysics
Atsuki Fukutani, Walter Herzog
Summary: This study found that very quick stretches can affect the magnitude of residual force enhancement, although there was no significant difference between muscles. This can help explain the key mechanism for inducing residual force enhancement.
JOURNAL OF BIOMECHANICS
(2022)
Article
Biology
Shuyue Liu, Venus Joumaa, Walter Herzog
Summary: The steady-state isometric force of a muscle after active stretching is greater than that of a purely isometric contraction at the same length and activation level, a phenomenon known as residual force enhancement (rFE). The role of cross-bridge cycling in rFE was investigated, and it was found that fast stretching, which causes cross-bridge slipping, is associated with a loss of rFE.
JOURNAL OF EXPERIMENTAL BIOLOGY
(2022)
Review
Physiology
Walter Herzog
Summary: This article introduces the methods, applications, advantages, and disadvantages of single sarcomere/myofibril research, emphasizing its importance in uncovering the mechanisms of muscle contraction.
FRONTIERS IN PHYSIOLOGY
(2022)
Article
Health Care Sciences & Services
Walter Herzog, Peter Kevorkian, Brent Russell, Joel Alcantara
Summary: The objective of this study was to quantify the forces exerted by a single chiropractor on children and adults during high-velocity, low-amplitude spinal manipulations and evaluate the correlation of forces to age. The results showed that most outcome variables increased with the age of the patient. This study demonstrated the feasibility of measuring the forces used by a chiropractor in clinical practice on patients of different ages.
JOURNAL OF MANIPULATIVE AND PHYSIOLOGICAL THERAPEUTICS
(2022)
Article
Engineering, Biomedical
Faruk Ortes, Azim Jinha, Walter Herzog, Yunus Ziya Arslan
Summary: Muscle models based on the cross-bridge theory can represent the dynamic and nonlinear characteristics of muscle forces. Sensitivity analysis of a Huxley model showed that changes in detachment rate had the greatest effect on muscle forces during lengthening contractions, while changes in attachment rate and binding distance had the greatest effect on forces during shortening contractions. These results highlight the asymmetry between shortening and lengthening contractions and the challenges of accurately predicting forces using a single cross-bridge model.
PROCEEDINGS OF THE INSTITUTION OF MECHANICAL ENGINEERS PART H-JOURNAL OF ENGINEERING IN MEDICINE
(2022)
Article
Rehabilitation
Lindsay M. Gorrell, Andrew Sawatsky, W. Brent Edwards, Walter Herzog
Summary: This study measured the length changes of the vertebral artery during cervical spine manipulation and found that the artery elongated but was not stretched. However, further research is needed to assess the safety of cervical spine manipulation from a mechanical perspective.
JOURNAL OF MANUAL & MANIPULATIVE THERAPY
(2023)
Article
Sport Sciences
Matthew Zukowski, Walter Herzog, Matthew J. Jordan
Summary: This study examined the intraday reliability of two novel unilateral loaded jump protocols designed for long track speed skaters and correlated them with performance in speed skating. The results showed that unilateral loaded jump tests are reliable in speed skating athletes and can be used to diagnose and monitor lower-limb maximal muscle power capacity.
JOURNAL OF STRENGTH AND CONDITIONING RESEARCH
(2023)
Editorial Material
Biophysics
Heiliane de Brito Fontana, Taylor J. M. Dick, Seong-won Han, Walter Herzog
JOURNAL OF BIOMECHANICS
(2023)
Article
Engineering, Biomedical
Philippe Pouletaut, Yoann Tatarenko, Mashhour K. Chakouch, Meng Li, Venus Joumaa, John R. Hawse, Walter Herzog, Simon Chatelin, Sabine F. Bensamoun
Summary: The study aimed to compare the passive mechanical properties of soleus and extensor digitorum longus muscles at different scales in a mouse model. Results showed significant differences in passive mechanical properties at the macroscopic scale, highlighting the importance of scale in tissue characterization. This research contributes referent data for future studies on multiscale passive mechanical properties of muscles.
Article
Health Care Sciences & Services
Lindsay M. Gorrell, Philip J. Conway, Franziska Onasch, Walter Herzog
Summary: This study systematically investigated the electromyographic responses associated with manual high-velocity, low-amplitude spinal manipulation in individuals with mild neck disability. The results showed that cervical spinal manipulation resulted in the highest rate of electromyographic responses in muscles of the cervical spine, while responses in back muscles were highest after upper thoracic manipulations.
JOURNAL OF MANIPULATIVE AND PHYSIOLOGICAL THERAPEUTICS
(2022)
Article
Sport Sciences
Matthew J. Jordan, Nathaniel Morris, Sophia Nimphius, Per Aagaard, Walter Herzog
Summary: A retrospective analysis on routine countermovement jump testing in female elite alpine skiers revealed that ACL-reconstructed skiers may experience impaired SSC function for up to 5 years post-surgery, although limb-specific asymmetry decreases over time.
FRONTIERS IN SPORTS AND ACTIVE LIVING
(2022)
Article
Biophysics
Nathan D. Camarillo, Rafael Jimenez-Silva, Frances T. Sheehan
Summary: This article discusses the statistical dependence between multiple measurements from the same participant and provides recommendations for using these measurements when they are not independent.
JOURNAL OF BIOMECHANICS
(2024)
Article
Biophysics
J. Huet, A. -S. Boureau, A. Sarcher, C. Cornu, A. Nordez
Summary: Standard compression in freehand 3D ultrasound induces a bias in volume calculations, but minimal compression and gel pad methods have similar results. With a trained examiner and precautions, the bias can be minimized and become acceptable in clinical applications.
JOURNAL OF BIOMECHANICS
(2024)
Article
Biophysics
C. Lariviere, A. H. Eskandari, H. Mecheri, F. Ghezelbash, D. Gagnon, A. Shirazi-Adl
Summary: Recent developments in musculoskeletal modeling have focused on model customization. Personalization of the spine profile may affect estimates of spinal loading and stability. This study investigates the biomechanical consequences of changes in the spinal profile and finds that personalizing the spine profile has medium to large effects on trunk muscle forces and negligible to small effects on spinal loading and stability.
JOURNAL OF BIOMECHANICS
(2024)
Article
Biophysics
Luke T. Mattar, Arash B. Mahboobin, Adam J. Popchak, William J. Anderst, Volker Musahl, James J. Irrgang, Richard E. Debski
Summary: Exercise therapy fails in about 25.0% of cases for individuals with rotator cuff tears, and one reason for this failure may be the inability to strengthen and balance the muscle forces that keep the humeral head in the correct position. This study developed computational musculoskeletal models to compare the net muscle force before and after exercise therapy between successfully and unsuccessfully treated patients. The study found that unsuccessfully treated patients had less inferiorly oriented net muscle forces, which may increase the risk of impingement.
JOURNAL OF BIOMECHANICS
(2024)
Article
Biophysics
Natsuki Sado, Takeshi Edagawa, Toshihide Fujimori, Shogo Hashimoto, Yoshikazu Okamoto, Takahito Nakajima
Summary: The existing methods for predicting hip and lumbosacral joint centres in Japanese adults are biased and differ between sexes. We propose new regression equations that consider soft-tissue thickness, sex differences, and a height-directional measure, and validate them using leave-one-out cross-validation.
JOURNAL OF BIOMECHANICS
(2024)
Article
Biophysics
Peimin Yu, Xuanzhen Cen, Qichang Mei, Alan Wang, Yaodong Gu, Justin Fernandez
Summary: This study aimed to explore the intra-foot biomechanical differences among individuals with chronic ankle instability (CAI), copers, and healthy individuals during dynamic tasks. The study found that copers and CAI individuals had smaller dorsiflexion angles and copers presented a more eversion position compared to healthy participants. Copers also had greater dorsiflexion angles in the metatarsophalangeal joint and more inversion moments in the subtalar joint during certain tasks. These findings can help in designing interventions to restore ankle joint functions in CAI individuals.
JOURNAL OF BIOMECHANICS
(2024)
Article
Biophysics
Jon Skovgaard Jensen, Anders Holsgaard-Larsen, Anders Stengaard Sorensen, Per Aagaard, Jens Bojsen-Moller
Summary: This study investigates the biomechanical effects of robot-assisted body weight unloading (BWU) on gait patterns in healthy young adults. The results show that dynamic robot-assisted BWU enables reduced kinetic requirements without distorting biomechanically normal gait patterns during overground walking.
JOURNAL OF BIOMECHANICS
(2024)