Muscle dynamics in skipjack tuna: timing of red muscle shortening in relation to activation and body curvature during steady swimming

1999 ◽  
Vol 202 (16) ◽  
pp. 2139-2150 ◽  
Author(s):  
R.E. Shadwick ◽  
S.L. Katz ◽  
K.E. Korsmeyer ◽  
T. Knower ◽  
J.W. Covell
Keyword(s):  
Fork Length ◽  
Muscle Length ◽  
The Body ◽  
Emg Activity ◽  
Skipjack Tuna ◽  
Force Transmission ◽  
Muscle Strain ◽  
Muscle Shortening ◽  
Red Muscle ◽  
Length Changes

Cyclic length changes in the internal red muscle of skipjack tuna (Katsuwonus pelamis) were measured using sonomicrometry while the fish swam in a water tunnel at steady speeds of 1.1-2.3 L s(−)(1), where L is fork length. These data were coupled with simultaneous electromyographic (EMG) recordings. The onset of EMG activity occurred at virtually the same phase of the strain cycle for muscle at axial locations between approximately 0.4L and 0.74L, where the majority of the internal red muscle is located. Furthermore, EMG activity always began during muscle lengthening, 40–50 prior to peak length, suggesting that force enhancement by stretching and net positive work probably occur in red muscle all along the body. Our results support the idea that positive contractile power is derived from all the aerobic swimming muscle in tunas, while force transmission is provided primarily by connective tissue structures, such as skin and tendons, rather than by muscles performing negative work. We also compared measured muscle length changes with midline curvature (as a potential index of muscle strain) calculated from synchronised video image analysis. Unlike contraction of the superficial red muscle in other fish, the shortening of internal red muscle in skipjack tuna substantially lags behind changes in the local midline curvature. The temporal separation of red muscle shortening and local curvature is so pronounced that, in the mid-body region, muscle shortening at each location is synchronous with midline curvature at locations that are 7–8 cm (i.e. 8–10 vertebral segments) more posterior. These results suggest that contraction of the internal red muscle causes deformation of the body at more posterior locations, rather than locally. This situation represents a unique departure from the model of a homogeneous bending beam, which describes red muscle strain in other fish during steady swimming, but is consistent with the idea that tunas produce thrust by motion of the caudal fin rather than by undulation of segments along the body.

Muscle length changes during swimming in scup: sonomicrometry verifies the anatomical high-speed cine technique.

1996 ◽  
Vol 199 (2) ◽  
pp. 459-463 ◽  
Author(s):  
D J Coughlin ◽  
L Valdes ◽  
L C Rome
Keyword(s):  
High Speed ◽  
Muscle Length ◽  
Fish Muscles ◽  
Muscle Shortening ◽  
Red Muscle ◽  
Independent Technique ◽  
Loop Technique ◽  
Length Changes ◽  
Work Loop

Recent attempts to determine how fish muscles are used to power swimming have employed the work loop technique (driving isolated muscles using their in vivo strain and stimulation pattern). These muscle strains have in turn been determined from the anatomical high-speed cine technique. In this study, we used an independent technique, sonomicrometry, to attempt to verify these strain measurements and the conclusions based on them. We found that the strain records measured from sonomicrometry and the anatomical-cine techniques were very similar. The ratio of the strain measured from sonomicrometry to that from the anatomical-cine technique was remarkably close to unity (1.046 +/- 0.013, mean +/- S.E.M., N = 15, for transducers placed on the muscle surface and corrected for muscle depth, and 0.921 +/- 0.028, N = 8, in cases where the transducers were inserted to the average depth of the red muscle). These measurements also showed that red muscle shortening occurs simultaneously with local backbone curvature, unlike previous results which suggested that white muscle shortening during the escape response occurs prior to the change in local backbone curvature.

Red muscle activation patterns in yellowfin (Thunnus albacares) and skipjack (Katsuwonus pelamis) tunas during steady swimming

1999 ◽  
Vol 202 (16) ◽  
pp. 2127-2138 ◽  
Author(s):  
T. Knower ◽  
R.E. Shadwick ◽  
S.L. Katz ◽  
J.B. Graham ◽  
C.S. Wardle
Keyword(s):  
Muscle Activation ◽  
Fork Length ◽  
Force Transducer ◽  
The Body ◽  
Thunnus Albacares ◽  
Katsuwonus Pelamis ◽  
Activation Patterns ◽  
Muscle Activation Patterns ◽  
Red Muscle ◽  
Swimming Mode

To learn about muscle function in two species of tuna (yellowfin Thunnus albacares and skipjack Katsuwonus pelamis), a series of electromyogram (EMG) electrodes was implanted down the length of the body in the internal red (aerobic) muscle. Additionally, a buckle force transducer was fitted around the deep caudal tendons on the same side of the peduncle as the electrodes. Recordings of muscle activity and caudal tendon forces were made while the fish swam over a range of steady, sustainable cruising speeds in a large water tunnel treadmill. In both species, the onset of red muscle activation proceeds sequentially in a rostro-caudal direction, while the offset (or deactivation) is nearly simultaneous at all sites, so that EMG burst duration decreases towards the tail. Muscle duty cycle at each location remains a constant proportion of the tailbeat period (T), independent of swimming speed, and peak force is registered in the tail tendons just as all ipsilateral muscle deactivates. Mean duty cycles in skipjack are longer than those in yellowfin. In yellowfin red muscle, there is complete segregation of contralateral activity, while in skipjack there is slight overlap. In both species, all internal red muscle on one side is active simultaneously for part of each cycle, lasting 0.18T in yellowfin and 0.11T in skipjack. (Across the distance encompassing the majority of the red muscle mass, 0.35-0.65L, where L is fork length, the duration is 0.25T in both species.) When red muscle activation patterns were compared across a variety of fish species, it became apparent that the EMG patterns grade in a progression that parallels the kinematic spectrum of swimming modes from anguilliform to thunniform. The tuna EMG pattern, underlying the thunniform swimming mode, culminates this progression, exhibiting an activation pattern at the extreme opposite end of the spectrum from the anguilliform mode.

INTRA-, EXTRA- AND INTERMUSCULAR MYOFASCIAL FORCE TRANSMISION OF SYNERGISTS AND ANTAGONISTS: EFFECTS OF MUSCLE LENGTH AS WELL AS RELATIVE POSITION

2002 ◽  
Vol 02 (03n04) ◽  
pp. 405-419 ◽  
Author(s):  
PETER A. HUIJING
Keyword(s):  
Connective Tissue ◽  
Relative Position ◽  
Muscle Length ◽  
Force Transmission ◽  
Muscle Belly ◽  
Myofascial Force Transmission ◽  
Antagonist Muscles ◽  
Length Changes ◽  
Edl Muscle

The concepts of intramuscular myofascial force transmission is reintroduced and reviewed on the basis of experiments involving tenotomy and aponeurotomy of dissected rat EDL muscle studied in situ. Results from experiments with measurements of force of EDL muscle, of which the muscle belly was not dissected (i.e. the muscle is surrounded by its natural connective tissue milieu) are discussed. In such experiments, force was measured at proximal as well as distal EDL tendons. Examples of experimental evidence for both extramuscular and intermuscular myofascial force transmission within the rat anterior crural compartment are presented. Evidence is presented also for differential effects of proximal and distal lengthening on myofascial force transmission from EDL, even for the case in which symmetric length changes were imposed on the muscle. It is shown that myofascial force transmission effects are not limited to synergists located within one compartment, but do also play a very substantial role in the interaction between antagonist muscles in neighbouring anterior crural and peroneal compartments.

scholarly journals Neuromuscular control of anguilliform locomotion: patterns of red and white muscle activity during swimming in the american eel anguilla rostrata

1998 ◽  
Vol 201 (23) ◽  
pp. 3245-3256 ◽  
Author(s):  
G. B. Gillis
Keyword(s):  
Swimming Speed ◽  
Muscle Activity ◽  
White Muscle ◽  
Neuromuscular Control ◽  
Emg Activity ◽  
Anguilla Rostrata ◽  
Significant Shift ◽  
Muscle Strain ◽  
Body Form ◽  
Red Muscle

Two areas that have received substantial attention in investigations of muscle activity during fish swimming are (1) patterns of fiber type recruitment with swimming speed and (2) the timing of muscle activation in relation to muscle strain. Currently, very little is known about either of these areas in eels, which represent an extreme body form among fishes and utilize a mode of locomotion found at one end of the undulatory spectrum(anguilliform locomotion). To assess how this swimming mode and body form influence the neuromuscular control of swimming, I recorded electromyographic data from red and white muscle at four positions, 0.3L,0.45L, 0.6L and 0.75L, where L is body length, in eels (Anguilla rostrata)simultaneously video-taped (250 fields s-1) swimming at three speeds, 0.5,0.75 and 1.0 L s-1. As in other fish, exclusively red muscle is used at slow swimming speeds and white muscle is additionally recruited at higher swimming speeds. However, this study also revealed a novel posterior-to-anterior pattern of muscle recruitment with increasing swimming speed. At slow speeds, anteriorly located muscles are never active, muscle strain is negligible and forward thrust must be generated by posterior muscles. As speed increases, more anterior muscles are additionally recruited. Electromyogram (EMG) burst durations typically occupy between 0.2 and 0.3 undulatory cycles, irrespective of speed or position. EMG burst intensity increases significantly with swimming speed. The onset of EMG activity typically occurred near the end of muscle lengthening, whereas the offset of EMG activity occurred during shortening(typically before the muscle's return to resting length). There was a significant shift in red muscle onset times such that anterior muscles were typically active later in their strain cycle than posterior muscles. When red muscle activity patterns across various fish taxa are compared,differences in propulsive wavelength among species are related to differences in muscle activity, providing insight into the underlying neuromuscular bases of differences among undulatory swimming modes.

Mechanical action of the internal intercostal muscles in dogs

1993 ◽  
Vol 75 (6) ◽  
pp. 2360-2367 ◽  
Author(s):  
A. F. DiMarco ◽  
G. S. Supinski ◽  
B. Simhai ◽  
J. R. Romaniuk
Keyword(s):  
Muscle Length ◽  
Mechanical Action ◽  
Abdominal Muscle ◽  
Electrical Activation ◽  
Positive End Expiratory Pressure ◽  
Rib Cage ◽  
Muscle Shortening ◽  
Anesthetized Dogs ◽  
Length Changes ◽  
Muscle Section

The pattern of electrical activation and muscle length changes of the internal intercostal (II) muscles (9th or 10th interspace) of the lower rib cage were evaluated in supine anesthetized dogs. Studies were performed during resting breathing and expiratory threshold loading. Results were compared with simultaneous measurements of the better-studied triangularis sterni muscle (4th interspace). In general, both muscles lengthened with passive inflation and shortened with passive deflation. During resting breathing, both the II and TS muscles were electrically active and shortened below resting length, 7.7 +/- 1.6% (SE) and 5.3 +/- 1.7%, respectively. With the addition of positive end-expiratory pressure, the degree of electrical activation and muscle shortening increased progressively for both muscles, although to a somewhat greater extent for II muscles. Isolated denervation of the II muscles eliminated their shortening during resting breathing and often resulted in muscle lengthening, indicating that II muscle shortening was secondary to its own activation. Expiration was associated with lateral inward movement of the lower rib cage below its relaxation position. This motion was not significantly affected by abdominal muscle section but was markedly reduced by bilateral II denervation (7th-11th spaces). Our results indicate that the II muscles of the lower rib cage 1) are electrically active and shorten below resting length during resting breathing, 2) respond to positive end-expiratory pressure by increasing their level of activation and degree of shortening, and 3) are primarily responsible for inward lateral motion of the lower rib cage below its relaxation position during expiration.

Effects of tracheal airway occlusion on hyoid muscle length and upper airway volume

1989 ◽  
Vol 67 (6) ◽  
pp. 2296-2302 ◽  
Author(s):  
E. van Lunteren ◽  
M. A. Haxhiu ◽  
N. S. Cherniack
Keyword(s):  
Tidal Volume ◽  
Muscle Length ◽  
Upper Airway ◽  
Lung Inflation ◽  
Airway Occlusion ◽  
Muscle Shortening ◽  
Tidal Changes ◽  
Length Changes ◽  
Complex Relationships ◽  
Upper Airway Muscles

Complex relationships exist among electromyograms (EMGs) of the upper airway muscles, respective changes in muscle length, and upper airway volume. To test the effects of preventing lung inflation on these relationships, recordings were made of EMGs and length changes of the geniohyoid (GH) and sternohyoid (SH) muscles as well as of tidal changes in upper airway volume in eight anesthetized cats. During resting breathing, tracheal airway occlusion tended to increase the inspiratory lengthening of GH and SH. In response to progressive hypercapnia, the GH eventually shortened during inspiration in all animals; the extent of muscle shortening was minimally augmented by airway occlusion despite substantial increases in EMGs. SH lengthened during inspiration in six of eight animals under hypercapnic conditions, and in these cats lengthening was greater during airway occlusion even though EMGs increased. Despite the above effects on SH and GH length, upper airway tidal volume was increased significantly by tracheal occlusion under hypercapnic conditions. These data suggest that the thoracic and upper airway muscle reflex effects of preventing lung inflation during inspiration act antagonistically on hyoid muscle length, but, because of the mechanical arrangement of the hyoid muscles relative to the airway and thorax, they act agonistically to augment tidal changes in upper airway volume. The augmentation of upper airway tidal volume may occur in part as a result of the effects of thoracic movements being passively transmitted through the hyoid muscles.

Ontogenetic changes in characteristics required for endothermy in juvenile black skipjack tuna (Euthynnus lineatus)

2000 ◽  
Vol 203 (20) ◽  
pp. 3077-3087 ◽  
Author(s):  
K.A. Dickson ◽  
N.M. Johnson ◽  
J.M. Donley ◽  
J.A. Hoskinson ◽  
M.W. Hansen ◽  
...  
Keyword(s):  
Muscle Mass ◽  
Heat Production ◽  
Citrate Synthase ◽  
Specific Activity ◽  
Production Capacity ◽  
Fork Length ◽  
Minimum Size ◽  
Skipjack Tuna ◽  
Ontogenetic Changes ◽  
Red Muscle

To characterize better the development of endothermy in tunas, we assessed how the abilities to generate heat and to conserve heat within the aerobic, slow-twitch (red) myotomal muscle using counter-current heat exchangers (retia) change with size in juvenile black skipjack tuna (Euthynnus lineatus) above and below the hypothesized minimum size for endothermy of 207 mm fork length (FL). Early juvenile scombrids (10–77 mm FL) collected off the Pacific coast of Panama were raised to larger sizes at the Inter-American Tropical Tuna Commission Laboratory at Achotines Bay, Panama. Evidence of central and lateral rete blood vessels was found in E. lineatus as small as 95.9 mm FL and 125 mm FL, respectively. In larger E. lineatus juveniles (up to 244 mm FL), the capacity for heat exchange increased with fork length as a result of increases in rete length, rete width and the number of vessel rows. The amount (g) of red muscle increased exponentially with fork length in both E. lineatus (105–255 mm FL) and a closely related ectothermic species, the sierra Spanish mackerel Scomberomorus sierra (151–212 mm FL), but was greater in E. lineatus at a given fork length. The specific activity (international units g(−)(1)) of the enzyme citrate synthase in red muscle, an index of tissue heat production potential, increased slightly with fork length in juvenile E. lineatus (84. 1–180 mm FL) and S. sierra (122–215 mm FL). Thus, total red muscle heat production capacity (red muscle citrate synthase activity per gram times red muscle mass in grams) increased with fork length, primarily because of the increase in red muscle mass. Below 95.9 mm FL, E. lineatus cannot maintain red muscle temperature (T(m)) above the ambient water temperature (T(a)) because juveniles of this size lack retia. Above 95.9 mm FL, the relationship between T(x) (T(m)-T(a)) and FL for E. lineatus diverges from that for the ectothermic S. sierra because of increases in the capacities for both heat production and heat retention that result in the development of endothermy.

Scaling of muscle performance during escape responses in the fish myoxocephalus scorpius L

1998 ◽  
Vol 201 (7) ◽  
pp. 913-923 ◽  
Author(s):  
R James ◽  
I A Johnston
Keyword(s):  
Power Output ◽  
Muscle Power ◽  
The Body ◽  
Shortening Velocity ◽  
Scaling Relationships ◽  
Muscle Shortening ◽  
Length Changes ◽  
Escape Responses ◽  
Myoxocephalus Scorpius ◽  
Muscle Power Output

Fast-starts associated with escape responses were studied in short-horn sculpin (Myoxocephalus scorpius L.), ranging from 5.5 to 32 cm in total length (L). Electromyography and sonomicrometry were used simultaneously to measure muscle activation and length changes, respectively, in the superficial layers of fast muscle in rostral myotomes. Escape responses consisted of a half tailbeat to bend the body into a C-shape (C-bend), another half tailbeat (contralateral contraction), followed by one or two more tailbeats and/or a gliding phase. The scaling relationships for both muscle strain and shortening duration differed between the C-bend and the contralateral contraction. As a result, relative muscle shortening velocity (V/V0) scaled as -1.18L1.06 for the C-bend and as 1.23L-0. 66 for the contralateral contraction. Therefore, the scaling relationships for muscle shortening velocity varied throughout the time course of the escape response. Muscle power output was determined by using the work-loop technique to subject isolated muscle fibres to in vivo strain and stimulation patterns. Plots of the instantaneous muscle forces and velocities achieved during the contralateral contraction were found to deviate from the steady-state force-velocity relationship. Maximum instantaneous muscle power output was independent of body size, with mean maximum values of 307 and 222 W kg-1 wet muscle mass for the C-bend and the contralateral contraction, respectively. <P>

scholarly journals Spatial variation in fast muscle function of the rainbow troutOncorhynchus mykissduring fast-starts and sprinting

2001 ◽  
Vol 204 (13) ◽  
pp. 2239-2250 ◽  
Author(s):  
D. J. Ellerby ◽  
J. D. Altringham
Keyword(s):  
Muscle Power ◽  
Fork Length ◽  
The Body ◽  
Fast Muscle ◽  
Emg Activity ◽  
Muscle Fibres ◽  
Muscle Recruitment ◽  
Axial Shift ◽  
Stage 1 ◽  
Sprint Swimming

SUMMARYFish fast-starts and sprints are rapid kinematic events powered by the lateral myotomal musculature. A distinction can be made between fast-starts and sprint-swimming activity. Fast-starts are kinematic events involving rapid, asymmetrical movements. Sprints involve a series of symmetrical, high-frequency tailbeats that are kinematically similar to lower-frequency, sustained swimming. The patterns of muscle recruitment and strain associated with these swimming behaviours were determined using electromyography and sonomicrometry. Axial patterns of fast muscle recruitment during sprints were similar to those in slow muscle in that the duration of electromyograhic (EMG) activity decreased in a rostro-caudal direction. There was also an axial shift in activity relative to the strain cycle so that activity occurred relatively earlier in the caudal region. This may result in caudal muscle performing a greater proportion of negative work and acting as a power transmitter as well as a power producer. The threshold tailbeat frequency for recruitment of fast muscle differed with location in the myotome. Superficial muscle fibres were recruited at lower tailbeat frequencies and shortening velocities than those deeper in the musculature. During sprints, fast muscle strain ranged from ±3.4%l0 (where l0 is muscle resting length) at 0.35FL (where FL is fork length) to ±6.3%l0 at 0.65FL. Fast-starts involved a prestretch of up to 2.5%l0 followed by shortening of up to 11.3%l0. Stage 1 EMG activity began simultaneously, during muscle lengthening, at all axial locations. Stage 2 EMG activity associated with the major contralateral contraction also commenced during lengthening and proceeded along the body as a wave. Onset of muscle activity during lengthening may enhance muscle power output.

Influence of submaximal isometric contractions of the hamstrings on electromyography activity and force while functioning as hip extensors

2020 ◽  
pp. 1-8
Author(s):  
Dasom Oh ◽  
Wootaek Lim
Keyword(s):  
Prone Position ◽  
Supine Position ◽  
Isometric Contraction ◽  
Muscle Length ◽  
Biceps Femoris ◽  
Emg Activity ◽  
Isometric Contractions ◽  
Significant Difference ◽  
Extension Force ◽  
Long Head

BACKGROUND: Although the medial and lateral hamstrings are clearly distinct anatomically and have different functions in the transverse plane, they are often considered as one muscle during rehabilitation. OBJECTIVE: The purpose of the study was to compare the electromyographic (EMG) activity between the prone position and the supine position during maximal isometric contraction and to additionally confirm the effect of submaximal isometric contractions on EMG activity of medial and lateral hamstrings, and force. METHODS: In the prone position, EMG activities of the long head of biceps femoris (BFLH) and semitendinosus (ST) were measured during the maximal isometric contraction. In the supine position, hip extension force with EMG activity were measured during the maximal and the submaximal isometric contractions. RESULTS: EMG activity in the prone position was significantly decreased in the supine position. In the supine position, there was a significant difference between the BFLH and ST during the maximal isometric contraction, but not during the submaximal isometric contractions. CONCLUSIONS: The dependence on the hamstrings could be relatively lower during hip extensions. When the medial and lateral hamstrings are considered separately, the lateral hamstrings may show a more active response, with increased muscle length, in clinical practice.

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