scholarly journals In vivo muscle force and elastic energy storage during steady-speed hopping of tammar wallabies (Macropus eugenii)

1995 ◽  
Vol 198 (9) ◽  
pp. 1829-1841 ◽  
Author(s):  
A Biewener ◽  
R Baudinette
Keyword(s):  
Energy Storage ◽  
Elastic Energy ◽  
Energy Recovery ◽  
High Speed ◽  
Muscle Activation ◽  
Metabolic Energy ◽  
Flexor Digitorum Longus ◽  
Foot Placement ◽  
Flexor Digitorum

In order to evaluate the role of elastic energy recovery in the hopping of macropodids, in vivo measurements of muscle­tendon forces using buckle force transducers attached to the tendons of the gastrocnemius (G), plantaris (PL) and flexor digitorum longus (FDL) of tammar wallabies were made as the animals hopped on a treadmill at speeds ranging from 2.1 to 6.3 m s-1. These muscles and tendons constitute the main structures that are most important in energy storage and recovery. Electromyographic recordings from the lateral gastrocnemius and plantaris muscles, together with high-speed films (200 frames s-1) and video (60 fields s-1), were also used to correlate muscle activation and kinematic patterns of limb movement with force development. On the basis of in situ calibrations of the buckle transducers, we found that muscle forces and elastic energy storage increased with increased hopping speed in all three muscle­tendon units. Elastic energy recovery reached a maximum of 25 % of metabolic energy expenditure at 6.3 m s-1 and is probably greater than this at higher speeds. Force sharing among the three muscles was consistently maintained over this range of speeds in terms of recruitment. Although forces and stresses were generally comparable within the gastrocnemius and plantaris muscles, maximal tendon stresses were considerably greater in the gastrocnemius, because of its smaller cross-sectional area (peak muscle stress: 227 versus 262 kPa; peak tendon stress: 36 versus 32 MPa, G versus PL). As a result, energy storage was greatest in the gastrocnemius tendon despite its much shorter length, which limits its volume and, hence, energy storage capacity, compared with PL and FDL tendons. Forces and stresses (17 MPa maximum) developed within the FDL tendon were consistently much lower than those for the other two tendons. Peak stresses in these three tendons indicated safety factors of 3.0 for G, 3.3 for PL and 6.0 for FDL. The lower stresses developed within the tendons of the plantaris and, especially, the flexor digitorum longus may indicate the need to maintain sufficient stiffness for phalangeal control of foot placement, at the expense of reduced strain energy recovery.

Deactivation rate and shortening velocity as determinants of contractile frequency

1990 ◽  
Vol 259 (2) ◽  
pp. R223-R230 ◽  
Author(s):  
R. L. Marsh
Keyword(s):  
Energy Storage ◽  
Elastic Energy ◽  
High Speed ◽  
Adductor Muscle ◽  
Stride Frequency ◽  
Kinetic Properties ◽  
Shortening Velocity ◽  
Thermal Dependence ◽  
Jet Propulsion

The kinetic properties of muscle that could influence locomotor frequency include rate of activation, rate of cross-bridge "attachment", intrinsic shortening velocity, and rate of deactivation. The latter two mechanisms are examined using examples from high-speed running in lizards and escape swimming in scallops. During running, inertial loading and elastic energy storage probably mitigate the effects of thermal alterations in intrinsic muscle shortening velocity. The result is a rather low thermal dependence of stride frequency over a 15-20 degree C temperature range. However, at lower temperatures, the longer times required for deactivation cause the thermal dependence of frequency to increase greatly. Scallops use a single muscle to swim by jet propulsion. In vivo shortening velocity in these animals also shows a low thermal dependence. As with high-speed running, the mechanics of jet propulsion may limit the effects of thermally induced changes in intrinsic shortening velocity. The largest thermal effect during swimming is on the initial phase of valve opening. The effects of temperature on the rate of deactivation of the adductor muscle could play an important role in limiting reextension of the muscle, which is dependent on elastic energy storage in the hinge ligament. These examples illustrate that the relative importance of various intrinsic contractile properties in controlling locomotor performance depends on the mechanics of the movements.

scholarly journals Evidence for a vertebrate catapult: elastic energy storage in the plantaris tendon during frog jumping

2011 ◽  
Vol 8 (3) ◽  
pp. 386-389 ◽  
Author(s):  
Henry C. Astley ◽  
Thomas J. Roberts
Keyword(s):  
Energy Storage ◽  
Elastic Energy ◽  
High Speed ◽  
Angular Acceleration ◽  
Whole Body ◽  
Joint Motion ◽  
Joint Movement ◽  
Fascicle Length ◽  
Muscle Fascicle ◽  
Muscle Shortening

Anuran jumping is one of the most powerful accelerations in vertebrate locomotion. Several species are hypothesized to use a catapult-like mechanism to store and rapidly release elastic energy, producing power outputs far beyond the capability of muscle. Most evidence for this mechanism comes from measurements of whole-body power output; the decoupling of joint motion and muscle shortening expected in a catapult-like mechanism has not been demonstrated. We used high-speed marker-based biplanar X-ray cinefluoroscopy to quantify plantaris muscle fascicle strain and ankle joint motion in frogs in order to test for two hallmarks of a catapult mechanism: (i) shortening of fascicles prior to joint movement (during tendon stretch), and (ii) rapid joint movement during the jump without rapid muscle-shortening (during tendon recoil). During all jumps, muscle fascicles shortened by an average of 7.8 per cent (54% of total strain) prior to joint movement, stretching the tendon. The subsequent period of initial joint movement and high joint angular acceleration occurred with minimal muscle fascicle length change, consistent with the recoil of the elastic tendon. These data support the plantaris longus tendon as a site of elastic energy storage during frog jumping, and demonstrate that catapult mechanisms may be employed even in sub-maximal jumps.

scholarly journals The Cross-Bridge Spring: Can Cool Muscles Store Elastic Energy?

Science ◽  
2013 ◽  
Vol 340 (6137) ◽  
pp. 1217-1220 ◽  
Author(s):  
N. T. George ◽  
T. C. Irving ◽  
C. D. Williams ◽  
T. L. Daniel
Keyword(s):  
Energy Storage ◽  
Elastic Energy ◽  
Molecular Motors ◽  
High Speed ◽  
Mechanical Energy ◽  
Elastic Strain Energy ◽  
Time Resolved ◽  
X Ray ◽  
Cross Bridge ◽  
Cross Bridges

Muscles not only generate force. They may act as springs, providing energy storage to drive locomotion. Although extensible myofilaments are implicated as sites of energy storage, we show that intramuscular temperature gradients may enable molecular motors (cross-bridges) to store elastic strain energy. By using time-resolved small-angle x-ray diffraction paired with in situ measurements of mechanical energy exchange in flight muscles of Manduca sexta, we produced high-speed movies of x-ray equatorial reflections, indicating cross-bridge association with myofilaments. A temperature gradient within the flight muscle leads to lower cross-bridge cycling in the cooler regions. Those cross-bridges could elastically return energy at the extrema of muscle lengthening and shortening, helping drive cyclic wing motions. These results suggest that cross-bridges can perform functions other than contraction, acting as molecular links for elastic energy storage.

scholarly journals Elastic energy storage in the shoulder and the evolution of high-speed throwing in Homo

Nature ◽  
2013 ◽  
Vol 498 (7455) ◽  
pp. 483-486 ◽  
Author(s):  
Neil T. Roach ◽  
Madhusudhan Venkadesan ◽  
Michael J. Rainbow ◽  
Daniel E. Lieberman
Keyword(s):  
Energy Storage ◽  
Elastic Energy ◽  
High Speed

A Novelty Energy Storage Algorithm for High Speed Trains: Economical and Energy Saving Evaluation

2021 ◽  
Author(s):  
Mi̇ne Sertsöz
Keyword(s):  
Energy Storage ◽  
Energy Recovery ◽  
High Speed ◽  
Regenerative Braking ◽  
Utilization Rate ◽  
High Speed Train ◽  
Rail Systems ◽  
High Speed Trains ◽  
Braking Energy Recovery

Abstract Increasing the utilization rate of regenerative braking energy in rail systems is one of the ongoing applications increasing in significance in recent years. This study develops a novelty algorithm within the scope of this objective and provides the calculation of the regenerative braking energy recovery rate and then making a decision for storage or back to grid of this energy. Afterwards, the regenerative braking energy was calculated with the help of this algorithm for Eskisehir-Ankara and Ankara-Eskisehir trips in two different passengers (load) scenarios, using the YHT 65000 high-speed train, which was chosen as a case study. Then, with a decision maker added to this classical regenerative braking energy algorithm, it will be decided whether this energy will be stored or forward back into the grid for the purpose of providing non-harmonic energy to the grid.

scholarly journals Presence of adipose tissue along the posteromedial tibial border

2021 ◽  
Vol 8 (1) ◽  
Author(s):  
Okunuki Takumi ◽  
Tanaka Hirofumi ◽  
Akuzawa Hiroshi ◽  
Yabiku Hiroki ◽  
Maemichi Toshihiro ◽  
...  
Keyword(s):  
Adipose Tissue ◽  
Gross Anatomy ◽  
Medial Malleolus ◽  
Posterior Tibial Tendon ◽  
Flexor Digitorum Longus ◽  
Significant Difference ◽  
Fat Fraction ◽  
Flexor Digitorum ◽  
Fat Pads

Abstract Purpose The flexor digitorum longus and posterior tibial tendon as well as the perforating veins are located along the distal posteromedial tibial border. Adipose tissue may surround these structures and possibly play a role in reducing mechanical stress. This study aimed to examine the adipose tissue along the posteromedial tibial border via magnetic resonance imaging (MRI), ultrasound, and gross anatomical examination. Methods The lower legs of 11 healthy individuals were examined every 3 cm from the medial malleolus using MRI and ultrasound. The fat fraction was calculated using fat fraction images. In addition, the gross anatomy of the flexor digitorum longus origin and adipose tissue along the posteromedial tibial border was examined in seven fresh cadavers. The fat fraction was compared at different heights along the posteromedial tibial border and in Kager’s fat pads; we also compared the height of the flexor digitorum longus origin and adipose tissue. Results In vivo, the adipose tissue was identified along the entire posteromedial tibial border using MRI and ultrasound. There was no significant difference in fat fraction between Kager’s fat pads and the adipose tissue along the posteromedial tibial border, except at the 6 cm mark. All seven cadavers presented adipose tissue along the posteromedial tibial border, significantly more distal than the flexor digitorum longus origin. Conclusion The adipose tissue was identified along the posteromedial tibial border via MRI, ultrasound, and gross anatomical examination; thus, this tissue may play a role in reducing friction and compressive stress in tendons.

Elastic energy storage in tendons: mechanical differences related to function and age

1990 ◽  
Vol 68 (3) ◽  
pp. 1033-1040 ◽  
Author(s):  
R. E. Shadwick
Keyword(s):  
Mechanical Properties ◽  
Tensile Strength ◽  
Elastic Modulus ◽  
Energy Storage ◽  
Elastic Energy ◽  
Storage Element ◽  
Extensor Tendons ◽  
Growth And Aging ◽  
And Function

We investigated the possibility that tendons that normally experience relatively high stresses and function as springs during locomotion, such as digital flexors, might develop different mechanical properties from those that experience only relatively low stresses, such as digital extensors. At birth the digital flexor and extensor tendons of pigs have identical mechanical properties, exhibiting higher extensibility and mechanical hysteresis and lower elastic modulus, tensile strength, and elastic energy storage capability than adult tendons. With growth and aging these tendons become much stronger, stiffer, less extensible, and more resilient than at birth. Furthermore, these alterations in elastic properties occur to a significantly greater degree in the high-load-bearing flexors than in the low-stress extensors. At maturity the pig digital flexor tendons have twice the tensile strength and elastic modulus but only half the strain energy dissipation of the corresponding extensor tendons. A morphometric analysis of the digital muscles provides an estimate of maximal in vivo tendon stresses and suggests that the muscle-tendon unit of the digital flexor is designed to function as an elastic energy storage element whereas that of the digital extensor is not. Thus the differences in material properties between mature flexor and extensor tendons are correlated with their physiological functions, i.e., the flexor is much better suited to act as an effective biological spring than is the extensor.

Absorbable Sutures in Tendon Repair

1995 ◽  
Vol 20 (4) ◽  
pp. 505-508 ◽  
Author(s):  
E. S. O’BROIN ◽  
M. J. EARLEY ◽  
H. SMYTH ◽  
A. C. B. HOOPER
Keyword(s):  
Tensile Strength ◽  
Rabbit Model ◽  
Tendon Repair ◽  
Tendon Healing ◽  
Flexor Digitorum Longus ◽  
Absorbable Sutures ◽  
Significant Difference ◽  
Intact Rabbit ◽  
Flexor Digitorum

The risks of foreign implantation may be avoided in tendon repair by the use of absorbable sutures, for example polydioxanone. In this study, the in vivo tensile strength half-life of 4/0 polydioxanone was found to be approximately 4 weeks. Using a rabbit model, we compared polydioxanone tendon repairs with polypropylene tendon repairs. Unilateral flexor digitorum longus repairs were performed on 46 rabbits using either polydioxanone or polypropylene. Tendons were harvested at 3 days, 2 weeks and 4 weeks and the tensile breaking strengths were obtained. 30 intact rabbit flexor digitorum longus tendons and 20 freshly repaired tendons were also tested. By 4 weeks, the repair strength had increased eight-fold from approximately 20 N to 166 N. The sutures made little contribution to the overall strength of a 4-week-old repair. There was no significant difference between polydioxanone and polypropylene repairs at any stage. These results show that polydioxanone repairs were as strong as polypropylene during the first critical weeks of tendon healing.

scholarly journals Intrinsic foot muscles contribute to elastic energy storage and return in the human foot

2019 ◽  
Vol 126 (1) ◽  
pp. 231-238 ◽  
Author(s):  
Luke A. Kelly ◽  
Dominic J. Farris ◽  
Andrew G. Cresswell ◽  
Glen A. Lichtwark
Keyword(s):  
Central Nervous System ◽  
Energy Storage ◽  
Elastic Energy ◽  
Mechanical Energy ◽  
Plantar Aponeurosis ◽  
Human Foot ◽  
Intrinsic Foot Muscles ◽  
Flexor Digitorum Brevis ◽  
The Central Nervous System ◽  
Flexor Digitorum

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.

scholarly journals Evidence of a tunable biological spring: elastic energy storage in aponeuroses varies with transverse strain in vivo

2019 ◽  
Vol 286 (1900) ◽  
pp. 20182764 ◽  
Author(s):  
Christopher J. Arellano ◽  
Nicolai Konow ◽  
Nicholas J. Gidmark ◽  
Thomas J. Roberts
Keyword(s):  
Energy Storage ◽  
Mechanical Behaviour ◽  
Elastic Energy ◽  
Biaxial Loading ◽  
Longitudinal Direction ◽  
General Assumption ◽  
Transverse Strain ◽  
Longitudinal Stiffness

Tendinous structures are generally thought of as biological springs that operate with a fixed stiffness, yet recent observations on the mechanical behaviour of aponeuroses (broad, sheet-like tendons) have challenged this general assumption. During in situ contractions, aponeuroses undergo changes in both length and width and changes in aponeuroses width can drive changes in longitudinal stiffness. Here, we explore if changes in aponeuroses width can modulate elastic energy (EE) storage in the longitudinal direction. We tested this idea in vivo by quantifying muscle and aponeuroses mechanical behaviour in the turkey lateral gastrocnemius during landing and jumping, activities that require rapid rates of energy dissipation and generation, respectively. We discovered that when aponeurosis width increased (as opposed to decreased), apparent longitudinal stiffness was 34% higher and the capacity of aponeuroses to store EE when stretched in the longitudinal direction was 15% lower. These data reveal that biaxial loading of aponeuroses allows for variation in tendon stiffness and energy storage for different locomotor behaviours.

Sign in / Sign up

Export Citation Format

Share Document