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In the comparative aspect the regeneration processes of striated muscles of hind left leg were researched in rats with posttraumatic reflex contractures against the background of physiotherapeutic treatment. Macroscopic and microscopic evaluation of pathomorphological changes has been conducted in this work. A relative area of myogenic elements (striated muscle elements), connective-tissue elements and neovasculature in the muscular-connective tissue in the scar in percentage has been determined using the method of point counting (field method). Depending on the signs of pain behavior (behavioral changes, additional signs), the intensity of myogenic pain syndrome (low, moderate, high, very high) has been studied. It has been established that the use of magnetic-laser therapy led to the formation of muscular-connective tissue scar up to the 28th day with a predominance of a portion of striated muscle tissue of 90.74±0.17%. Behavioral and motor responses became normalized; no pain was observed in 56% of rats, pain intensity was low in 44%. In animals with the same trauma that were not treated, the portion of striated muscle tissue was 37.08±0.34%, and signs of pain of high and moderate intensity were observed. By the 28th day, the animals could brace against their hind limbs while moving, but due to a sharp restriction of the function of the left hind limb, they could not move freely. The obtained results are the basis for developing new approaches to improving the methods of remedial treatment of contractures using magnetic-laser therapy. [ABSTRACT FROM AUTHOR]

The dichotomy between smooth and striated myocytes is fundamental for bilaterian musculature, but its evolutionary origin is unsolved. In particular, interrelationships of visceral smooth muscles remain unclear. Absent in fly and nematode, they have not yet been characterized molecularly outside vertebrates. Here, we characterize expression profile, ultrastructure, contractility and innervation of the musculature in the marine annelid Platynereis dumerilii and identify smooth muscles around the midgut, hindgut and heart that resemble their vertebrate counterparts in molecular fingerprint, contraction speed and nervous control. Our data suggest that both visceral smooth and somatic striated myocytes were present in the protostome-deuterostome ancestor and that smooth myocytes later co-opted the striated contractile module repeatedly - for example, in vertebrate heart evolution. During these smooth-to-striated myocyte conversions, the core regulatory complex of transcription factors conveying myocyte identity remained unchanged, reflecting a general principle in cell type evolution. [ABSTRACT FROM AUTHOR]

To explain disparate decay rates of cytosolic Ca2+ and structural changes in the thin filaments during a twitch, we model the time course of Ca2+ bound troponin (Tn) resulting from the free Ca2+ transient of fast skeletal muscle. In fibers stretched beyond overlap, the decay of Ca2+ as measured by a change in fluo 3 fluorescence is significantly slower than the intensity decay of the meridional 1/38.5 nm-1 reflection of Tn; this is not simply explained by considering only the Ca2+ binding properties of Tn alone (Matsuo, T., Iwamoto, H., and Yagi, N. (2010). Biophys. J. 99, 193-200). We apply a comprehensive model that includes the known Ca2+ binding properties of Tn in the context of the thin filament with and without cycling crossbridges. Calculations based on the model predict that the transient of Ca2+ bound Tn correlates with either the fluo 3 time course in muscle with overlapping thin and thick filaments or the intensity of the meridional 1/38.5 nm-1 reflection in overstretched muscle. Hence, cycling crossbridges delay the dissociation of Ca2+ from Tn. Correlation with the fluo 3 fluorescence change is not causal given that the transient of Ca2+ bound Tn depends on sarcomere length, whereas the fluo-3 fluorescence change does not. Transient positions of tropomyosin calculated from the time course of Ca2+ bound Tn are in reasonable agreement with the transient of measured perturbations of the Tn repeat in overlap and non-overlap muscle preparations.

Bcl-2 and Bax proteins are expressed in cells of the tails of Pelophylax ridibundus larvae. We investigated the levels of these proteins in tails undergoing apoptosis. Apoptotic cells were observed in the epidermis, muscle and notochord of tails of different lengths. The apoptotic cells in epidermis exhibited the typical features of apoptosis. Amorphous masses and irregularities in striated muscle tissue undergoing apoptosis and apoptotic remnants in the notochord also were observed. In general, Bax staining in the epidermis, subepidermal fibroblast layer, muscle and notochord cells increased, while Bcl-2 staining decreased as the tail regressed. Our results suggest that during tail regression due to metamorphosis, Bcl-2 and Bax proteins play key roles in the apoptosis of tail epidermis, subepidermal fibroblast layer, muscle and notochord cells. [ABSTRACT FROM AUTHOR]

Following the onset of maturation, female athletes have a significantly higher risk for anterior cruciate ligament (ACL) injury compared with male athletes. While multiple sex differences in lower-extremity neuromuscular control and biomechanics have been identified as potential risk factors for ACL injury in females, the majority of these studies have focused specifically on the knee joint. However, increasing evidence in the literature indicates that lumbo-pelvic (core) control may have a large effect on knee-joint control and injury risk. This review examines the published evidence on the contributions of the trunk and hip to knee-joint control. Specifically, the sex differences in potential proximal controllers of the knee as risk factors for ACL injury are identified and discussed. Sex differences in trunk and hip biomechanics have been identified in all planes of motion (sagittal, coronal and transverse). Essentially, female athletes show greater lateral trunk displacement, altered trunk and hip ulexion angles, greater ranges of trunk motion, and increased hip adduction and internal rotation during sport manoeuvres, compared with their male counterparts. These differences may increase the risk of ACL injury among female athletes. Prevention programmes targeted towards trunk and hip neuromuscular control may decrease the risk for ACL injuries. [ABSTRACT FROM AUTHOR]

The aim of this study was to evaluate the benefits and limitations of using three dimensional (3D) musculoskeletal modelling (LifeModeler™) in assessing the safety and efficacy of exercising on a seated biceps curl resistance training machine. Three anthropometric cases were studied, representing a 5th percentile female, 50th percentile and 95th percentile male. Results indicated that the LifeModeler™ default model was not adequate to solve the forward dynamics simulations. Therefore adjustments had to be made to the default model to successfully complete the forward dynamics simulations. The software was able to sufficiently highlight the shortcomings of the biceps curl machine's engineered adjustability in relation to the anthropometric dimensions of the studied cases, as the 5th percentile female could not be accommodated suitably on the machine. High lumbar spine anterior/posterior shear forces for all anthropometric cases and maximum muscle tensions for the female and 50th percentile male indicate that the seated biceps curl exercise may pose risks for injuries. To conclude, it appears that 3D musculoskeletal modelling can be used to evaluate resistance training equipment such as the seated biceps curl machine. However the limitations as indicated by this study must be taken into consideration, especially when using the default LifeModeler™ model. [ABSTRACT FROM AUTHOR]

Leptin administration increases fatty acid (FA) oxidation rates and decreases lipid storage in oxidative skeletal muscle, thereby improving insulin response. We have previously shown high-fat (HF) diets to rapidly induce skeletal muscle leptin resistance, prior to the disruption of normal muscle FA metabolism (increase in FA transport; accumulation of triacylglycerol, diacylglycerol, ceramide) that occurs in advance of impaired insulin signaling and glucose transport. All of this occurs within a 4-wk period. Conversely, exercise can rapidly improve insulin response, in as little as one exercise bout. Thus, if the early development of leptin resistance is a contributor to HF diet-induced insulin resistance (IR) in skeletal muscle, then it is logical to predict that the rapid restoration of insulin response by exercise training would be preceded by the recovery of leptin response. In the current study, we sought to determine 1) whether 1, 2, or 4 wk of exercise training was sufficient to restore leptin response in isolated soleus muscle of rats already consuming a HF diet (60% kcal), and 2) whether this preceded the training-induced corrections in FA metabolism and improved insulin-stimulated glucose transport. In the low-fat (LF)-fed control group, insulin increased glucose transport by 153% and leptin increased AMPK and ACC phosphorylation and the rate of palmitate oxidation (+73%). These responses to insulin and leptin were either severely blunted or absent following 4 wk of HF feeding. Exercise intervention decreased muscle ceramide content (-28%) and restored insulin-stimulated glucose transport to control levels within 1 wk; muscle leptin response (AMPK and ACC phosphorylation, FA oxidation) was also restored, but not until the 2-wk time point. In conclusion, endurance exercise training is able to restore leptin response, but this does not appear to be a necessary precursor for the restoration of insulin response. [ABSTRACT FROM AUTHOR]

The aim of this review is to highlight two emerging concepts for the elite athlete using the resistance-training model: (i) the short-term effects of testosterone (T) and cortisol (C) on the neuromuscular system; and (ii) the dose-response training role of these endogenous hormones. Exogenous evidence confirms that T and C can regulate long-term changes in muscle growth and performance, especially with resistance training. This evidence also confirms that changes in T or C concentrations can moderate or support neuromuscular performance through various short-term mechanisms (e.g. second messengers, lipid/protein pathways, neuronal activity, behaviour, cognition, motor-system function, muscle properties and energy metabolism). The possibility of dual T and C effects on the neuromuscular system offers a new paradigm for understanding resistance-training performance and adaptations. Endogenous evidence supports the short-term T and C effects on human performance. Several factors (e.g. workout design, nutrition, genetics, training status and type) can acutely modify T and/or C concentrations and thereby potentially influence resistance-training performance and the adaptive outcomes. This novel short-term pathway appears to be more prominent in athletes (vs non-athletes), possibly due to the training of the neuromuscular and endocrine systems. However, the exact contribution of these endogenous hormones to the training process is still unclear. Research also confirms a dose-response training role for basal changes in endogenous T and C, again, especially for elite athletes. Although full proof within the physiological range is lacking, this athlete model reconciles a proposed permissive role for endogenous hormones in untrained individuals. It is also clear that the steroid receptors (cell bound) mediate target tissue effects by adapting to exercise and training, but the response patterns of the membrane-bound receptors remain highly speculative. This information provides a new perspective for examining, interpreting and utilizing T and C within the elite sporting environment. For example, individual hormonal data may be used to better prescribe resistance exercise and training programmes or to assess the trainability of elite athletes. Possible strategies for acutely modifying the hormonal milieu and, thereafter, the performance/training outcomes were also identified (see above). The limitations and challenges associated with the analysis and interpretation of hormonal research in sport (e.g. procedural issues, analytical methods, research design) were another discussion point. Finally, this review highlights the need for more experimental research on humans, in particular athletes, to specifically address the concept of dual steroid effects on the neuromuscular system. [ABSTRACT FROM AUTHOR]

This series of reviews focuses on the most important neuromuscular function in many sport performances, the ability to generate maximal muscular power. Part 1 focuses on the factors that affect maximal power production, while part 2, which will follow in a forthcoming edition of Sports Medicine, explores the practical application of these findings by reviewing the scientific literature relevant to the development of training programmes that-most effectively enhance maximal power production. The ability of the neuromuscular system to generate maximal power is affected by a range of interrelated factors. Maximal muscular power is defined and limited by the force-velocity relationship and affected by the length-tension relationship. The ability to generate maximal power is influenced by the type of muscle action involved and, in particular, the time available to develop force, storage and utilization of elastic energy, interactions of contractile and elastic elements, potentiation of contractile and elastic filaments as well as stretch reflexes. Furthermore, maximal power production is influenced by morphological factors including fibre type contribution to whole muscle area, muscle architectural features and tendon properties as well as neural factors including motor unit recruitment, firing frequency, synchronization and intermuscular coordination. In addition, acute changes in the muscle environment (i.e. alterations resulting from fatigue, changes in hormone milieu and muscle temperature) impact the ability to generate maximal power. Resistance training has been shown to impact each of these neuromuscular factors in quite specific ways. Therefore, an understanding of the biological basis of maximal power production is essential for developing training programmes that effectively enhance maximal power production in the human. [ABSTRACT FROM AUTHOR]

Bone density and bone mass are commonly regarded as the essential parameters to describe fracture risk in osteology. Because fractures primarily depend on bone strength and secondarily on bone mass and density, bone strength should be the main parameter to describe fracture risk. The quantitative description of bone strength has the prerequisite that bone geometry is assessed despite bone density. Thus, volumetric osteodensitometric methods should be preferred, which enable the physician to evaluate parameters primarily associated with bone modeling or remodeling. Modeling describes the adaptation of bone geometry to applied muscular forces in contrast to remodeling representing bone turnover. The adaptation of bone geometry to muscle forces led to the term functional muscle-bone unit, which enables the physician to differentiate between primary and secondary bone diseases. Primary bone diseases are characterized by a defective adaptation of bone to muscle forces in contrast to secondary bone diseases, which are primary diseases of the neuromuscular system. Because muscle forces are essential in the feedback loop of bone adaptation to forces (mechanostat), the assessment of muscle function has become an essential part of osteologic diagnostics in pediatrics. Dynamometric and mechanographic methods have been introduced to properly characterize kinetic aspects of muscle function in children and adolescents. Therefore, emphasis should be put on the assessment of muscle function despite the evaluation of osteodensitometric parameters in pediatric osteology. [ABSTRACT FROM AUTHOR]

The present article reviews the physiological and performance effects of speed endurance training consisting of exercise bouts at near maximal intensities in already trained subjects. Despite a reduction in training volume, speed endurance training of endurance-trained athletes can maintain the oxidative capacity and improve intense short-duration/repeated high-intensity exercise performance lasting 30 s to 4 min, as it occurs in a number of sports. When combined with a basic volume of training including some aerobic high-intensity sessions, speed endurance training is also useful in enhancing performance during longer events, e.g. 40 K cycling and 10 K running. Athletes in team sports involving intense exercise actions and endurance aspects can also benefit from performing speed endurance training. These improvements don't appear to depend on changes in maximum oxygen uptake ( ), muscle substrate levels, glycolytic and oxidative enzymes activity, and membrane transport proteins involved in pH regulation. Instead they appear to be related to a reduced energy expenditure during submaximal exercise and a higher expression of muscle Na+,K+ pump α-subunits, which via a higher Na+,K+ pump activity during exercise may delay fatigue development during intense exercise. In conclusion, athletes from disciplines involving periods of intense exercise can benefit from the inclusion of speed endurance sessions in their training programs. [ABSTRACT FROM AUTHOR]

Since long, motor imagery has been recognized as a method for studying motor representations. In the last few years, important advances regarding the use of motor imagery have been made. In particular, issues concerning the functional equivalence between imagery and action have been addressed, and how equivalence affects the use of imagery to study motor representations. In this paper, we review recent findings in order to highlight the current state of knowledge about motor imagery and its relation to motor action. Three topics are discussed: (i) the imagery perspective, (ii) task complexity, and (iii) the importance of physical experience. It is shown how theses factors are closely related and how previous studies may have underestimated to what extent these factors affect the interpretation of results. Practical implications for imagery interventions are considered. It is concluded that if you cannot perform an action physically, you cannot imagine it in a way that is necessary for a high degree of functional equivalence. [ABSTRACT FROM AUTHOR]

We compared the lower limb muscle activation during uphill running (UR), level running (LR), and downhill running (DR). Eight male physically active subjects ran three slopes for 30 min at the given speed (55% vVO_{2}peak at LR), including DR (-6°), LR (0°), and UR (6°) in a random crossover, repeated measures design. Electromyographic (EMG) signals were collected from the dominated lower limb muscles: rectus femoris (RF), biceps femoris (BF), gastrocnemius (GAS), soleus, and tibialis anterior. Our results showed that greater EMG of RF was found with inclining slope (UR>LR>DR, p< 0.05); EMG of BF was greater during UR than during DR (p< 0.05); EMG of GAS differed significantly in the order: UR>DR>LR (p< 0.05). We concluded that significant differences regarding muscle activations among DR, LR, and UR were observed for the RF, BF, and GAS, especially when running opposing slopes (DR vs. UR). Additionally, when running toward uphill, the propulsive muscles, such as the RF and GAS seemed to exert more effort. In contrast, while running toward downhill, RF might work as an extensor muscle that was activated to a lesser extent, possibly due to its undergoing eccentric movement. [ABSTRACT FROM AUTHOR]

Intramuscular triacylglycerol (IMTG) is both a dynamic fat-storage depot that can expand during periods of elevated lipid availability and a fatty acid source that can be utilized during periods of increased energy expenditure in active individuals. Although many studies have investigated the lifestyle determinants of IMTG content, the results are far from consistent, and studies attempting to unravel the mechanisms behind IMTG metabolism are in their infancy. The limited evidence available suggests that the enzymes responsible for skeletal muscle lipolysis and IMTG synthesis play an important role in determining the fate of fatty acids and therefore the concentration of lipid metabolites and insulin sensitivity of skeletal muscle. This review provides a summary of current knowledge on the effects of acute and chronic exercise as well as energy intake and macronutrient composition of the diet upon the metabolism of IMTG and the implications for metabolic health. [ABSTRACT FROM AUTHOR]

Microarray technology permits the interrogation of nearly all expressed genes under a wide range of conditions. Patterns of gene expression in response to obesity and diabetes have yielded important insights into the pathogenesis of diabetes and its relationship to obesity. In muscle, microarray studies have motivated research into mitochondrial function. In adipose tissue, clues have pointed to the importance of inflammation in obesity. New adipocyte-derived hormones involved in insulin resistance have been found; a notable example is retinol binding protein 4. In liver, genes responsive to master regulators of lipid metabolism have been identified. In β-cells, genes involved in cell survival, cell proliferation, and insulin secretion have been identified. These studies have greatly expanded our understanding of mechanisms underlying the pathogenesis of obesity-induced diabetes. When combined with genetic information, microarray data can be used to construct causal network models linking gene expression with disease. [ABSTRACT FROM AUTHOR]

Aging skeletal muscle shows an increased time to peak force and relaxation and a decreased specific force, all of which could relate to changes in muscle Ca2+ handling. The purpose of this study was to determine if Ca2+-handling protein content and function are decreased in senescent gastrocnemius muscle and if initiating a training program in late middle age (LMA, 29 mo old) could improve function in senescent (34to 36-mo-old) muscle. LMA male Fischer 344 × Brown-Norway rats underwent 5-7 mo of treadmill training. Aging resulted in a decrease in maximal sarco(endo)plasmic reticulum Ca2+-ATPase (SERCA) activity and a decrease in Ca2+ release rate but no change in Ca2+ uptake rate. Efficiency of the Ca2+ pump was increased with age, as was the content of SERCA2a. Training caused a further increase in SERCA2a content. Aging also caused an increase in protein carbonyl and reactive nitrogen species damage accumulation, and both further increased with training. Consistent with the increase in oxidative damage, heat shock protein 70 content was increased with age and further increased with training. Together, these results suggest that while initiating exercise training in LMA augments the age-related increase in expression of heat shock protein 70 and the more efficient SERCA2a isoform, it did not prevent the decrease in SERCA activity and exacerbated oxidative damage in senescent gastrocnemius muscle. [ABSTRACT FROM AUTHOR]

Skeletal muscle has the ability to adapt and remodel after functional, mechanical, and metabolic stresses by activation of different adaptation mechanisms that induce gene expression, biochemical changes, and structural remodeling. Skeletal muscle cells continuously generate reactive oxygen and nitrogen species (RONS), which can act as mediators in cellular signaling pathways that regulate the adaptation mechanisms. There is strong evidence that indicates that RONS are generated in skeletal muscle cells during contractile activity and this induces the activation of transcription factors which modulate gene expression of antioxidant and protective proteins. Thus, it has been proposed that RONS act as signals that modulate the adaptation mechanisms in skeletal nmscle and other cells. Structural and functional changes occur in skeletal muscle during aging and are characterized by a reduction of muscle mass and force (sarcopenia). The causes are known, however, there is considerable support for an involvement of RONS in the process of aging and sarcopenia. Several studies indicate that adaptive responses of skeletal muscle that are activated and regulated by RONS are disrupted during aging. This reduction of skeletal muscle adaptation to contractile activity during aging might be responsible for the loss of muscle mass and function and the progressive deterioration of this organ. In summary, there is sufficient evidence that indicates that cellular redox regulation in skeletal muscle is crucial in the physiology and pathology of skeletal muscle. However, new methodologies and experimental models are required for understanding the complex biology of RONS in the cell. This will provide future interventions that mitigate pathologies and aging of skeletal muscle. [ABSTRACT FROM AUTHOR]

Mobilization of fatty acids from stored triacylglycerol (TO) in adipose tissue and skeletal muscle [intramyocellular triacylglycerol (IMTG)] requires activity of lipases. Although exercise training increases the lipolytic capacity of skeletal muscle, the expression of hormone-sensitive lipase (HSL) is not changed. Recently, adipose triglyceride lipase (ATGL) was identified as a TG-specific lipase in various rodent tissues. To investigate whether human skeletal muscle ATOL protein is regulated by endurance exercise training, 10 healthy young men completed 8 wk of supervised endurance exercise training. Western blotting analysis on lysates of skeletal muscle biopsy samples revealed that exercise training induced a twofold increase in skeletal muscle ATOL protein content. In contrast to ATOL, expression of comparative gene identification 58 (CGI-58), the activating protein of ATGL, and HSL protein was not significantly changed after the training period. The IMTG concentration was significantly decreased by 28% at termination of the training program compared with before. HSL-phoshorylation at Ser660 was increased, HSL-Ser659 phosporylation was unchanged, and HSL-phoshorylation at Ser565 was decreased altogether, indicating an enhanced basal activity of this lipase. No change was found in the expression of diacyiglycerol acyl transferase 1 (DGATI) after training. Inhibition of HSL with a monospecific, small molecule inhibitor (76-0079) and stimulation of ATGL with CGI-58 revealed that significant ATGL activity is present in human skeletal muscle. These results suggest that ATGL in addition to HSL may be important for human skeletal muscle lipolysis. [ABSTRACT FROM AUTHOR]

ADP is generally accepted as a key regulator of oxygen consumption both in isolated mitochondria and in permeabilized fibers from skeletal muscle. The present study explored inorganic phosphate in a similar regulatory role. Saponin permeabilized fibers and isolated mitochondria from type-I and type-II muscle from male Wistar rats were prepared. Respiration was measured while the medium P(i) concentration was gradually increased. The apparent K(m) values for P(i) were 607 +/- 17 microM and 405 +/- 15 microM (P < 0.0001) for type-I and type-II fibers, respectively. For isolated mitochondria the values were significantly lower than type-1 permeabilized fibers, 338 +/- 130 microM and 235 +/- 30 microM (P < 0.05), but not different with respect to fiber type. The reason for this difference in K(m) values in the permeabilized muscle is unknown, but a similar pattern has been observed for K(m) of ADP. Our data indicate that phosphate may play a role in regulation of oxygen consumption in vitro and in vivo. [ABSTRACT FROM AUTHOR]

The striated muscle forms an outer sleeve around the urethra and occupies about 80% of the wall. In humans more than 60% of the muscle consists of slow, fatigue resistant type I fibres whereas in male greyhounds only about 6% are type I. Most of the remainder (70% of fibres) are type IIa which are classified as fast but can contract for several hours with little decline in amplitude. Stimulation of pudendal but not pelvic nerves produces contraction of the striated muscle and a rapid increase in urethral pressure. Pelvic nerve branches enter the striated muscle sleeve but pass through it to supply the inner layer of smooth muscle. The striated muscles are well suited to maintain contraction necessary for continence. [ABSTRACT FROM AUTHOR]

Focuses on a study which determined whether endogenous angiotensin II (ANG II) augments arteriolar myogenic behavior in striated muscle. Reinforcement of myogenic responsiveness by ANG II; Effect of ANG II on arteriolar function and structure in salt-fed rats; Effect of bradykinin on arteriolar myogenic responsiveness.

Examines the effect of AMP-activated protein kinase activation on skeletal muscle glucose metabolism in awake rats. Infusion with 5-aminoimidazole-4-carboxamide 1-beta-D-ribofuranoside (AICAR) along with variable amounts of glucose; Assessment of glucose uptake in vitro using epitrochlearis muscle; Additive effect of combined AICAR and insulin on muscle glucose transport activity.

Investigates the effect of lactate on glucose transport and utilization in skeletal muscle. Infusion of sodium lactate and bicarbonate; Decrease of glucose uptake due to hyperlactatemia; Increase of pyruvate dehydrogenase protein; Effect of chronic hyperlactatemia on the expression of genes involved in glucose metabolism in muscle.

Determines whether tumor necrosis factor (TNF)-alpha, a cytokine produced by immune cells during skeletal muscle damage, decreases insulin responsiveness at the cellular level. Molecular mechanisms associated with TNF-alpha and insulin action; Linking of increase in TNF-alpha to insulin resistance in skeletal muscle.

Provides evidence linking the regulated expression of distinct acidic and basic troponin T isoform classes to the contractility of striated muscle. Comparison of the contractile properties of fibers from adult chicken breast muscle with those of the levator coccygeus muscle; Measurement of force and stiffness responses to Ca2+.

Examines the effects of the beta2-adrenoceptor agonist salbutamol on regulation of intracellular Ca2+ concentration in myotubes derived from neonatal mouse limb muscles. Confirmation of presence of sarcomeres through immunocytochemical staining; Inhibition of acetyl choline-induced intracellular calcium transients.

Suggests that the experience of flight activity may be of critical importance in achieving maximal expression of fatty acid binding protein in the pectoralis muscles of postfledgling and mature geese immediately before migration. Use of oxidated fatty acids as fuel for migratory flights; Transportation of fatty acid to mitochondria of active muscles.

Determines the importance of the muscle metaboreflex in control of blood flow to ischemic active skeletal muscle in dogs. Closed-loop gain of the muscle metaboreflex; Analysis of blood flow restoration by muscle metaboreflex; Reduction of blood flow to inactive tissues by tissue compression.

Describes the enhancement of the rate of force development by myosin phosphorylation in fast-twitch skeletal muscle. Calcium regulation of contraction force development; Influence of rate of tetanic force development; Phosphate incorporation by the regulatory light chain subunits of skeletal myosin.