Thermal acclimation in rainbow smelt, Osmerus mordax, leads to faster myotomal muscle contractile properties and improved swimming performance

Selenium (Se) is an important component of cellular seleno Ã¢â‚¬Âcompounds andan integral component of glutathione Peroxidase (GPx), which catalyzes thereduction of harmful radicals produced during muscular exercise. The currentstudy was carried out to evaluate the muscle contractile properties andfatigue resistance of gastrocnemius muscle under selenium supplementationschemes in sedentary and exercise protocols as well as measure the antioxidantenzymes activity and lipid peroxidation. Rats were divided into fourgroups; sedentary Selenium supplementation (S), exercise Selenium (SE)groups, sedentary control (SC) and exercise control (EC) groups. The ratswere fed with 80 μg/kg body weights selenium for six weeks. The exerciseprotocol consisted the 40 jumps up to the height of 40 cm for 6 Ã¢â‚¬Âweek. Themuscle fatigue protocol consisted the trains of pulses of 40 Hz at every secondfor at least 2 min. Significant (P<0.05) increase was observed in treatedgroups than control in the muscle contractile properties like twitch tension(Pt), contraction time (CT) and twitch/tetanic tension Ratio (Pt/Po Ratio),tetanic tension (Po) and EMG amplitude. Decreased EMG failure and increasedfatigue index were observed in ES group. Moreover, a significant(P<0.05) increase and decrease in the GPx activity and lipid peroxidation respectivelywas also reported than SC and EC group. While there were nochanges reported in the activity of CAT and SOD enzymes. This study revealedthat the Se with jumping exercise induces muscle contractile propertiesand decreases the muscular fatigue.

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Thermal acclimation and muscle contractile properties in cyprinid fish

AJP Regulatory Integrative and Comparative Physiology ◽

10.1152/ajpregu.1990.259.2.r231 ◽

1990 ◽

Vol 259 (2) ◽

pp. R231-R236 ◽

Cited By ~ 10

Author(s):

I. A. Johnston ◽

J. D. Fleming ◽

T. Crockford

Keyword(s):

Molecular Mechanisms ◽

Swimming Performance ◽

Force Production ◽

Rutilus Rutilus ◽

Temperature Acclimation ◽

Thermal Acclimation ◽

Contractile Properties ◽

Locomotory Activity ◽

Roach Rutilus Rutilus ◽

Goldfish Carassius Auratus

After several weeks of cold acclimation, the swimming performance of some fish is increased at low temperatures and decreased at high temperatures. The temperature compensation of locomotory activity involves changes in central patterns of muscle fiber recruitment and in the properties of the peripheral nervous system and muscle tissues. In some freshwater fish belonging to the family Cyprinidae, including the goldfish (Carassius auratus), the common carp (Cyprinus carpio), and the roach (Rutilus rutilus), the intrinsic contractile properties of muscles are modified by thermal acclimation. Parameters that can be altered by temperature acclimation in both fast and slow muscle fibers include isometric twitch contraction time, maximum force production, and unloaded shortening speed. The molecular mechanisms responsible for these changes in contractility are discussed.

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Muscle Contractile Properties Measured at Submaximal Electrical Amplitudes and Not at Supramaximal Amplitudes Are Associated with Repeated Sprint Performance and Fatigue Markers

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph182111689 ◽

2021 ◽

Vol 18 (21) ◽

pp. 11689

Author(s):

Alejandro Muñoz-López ◽

Moisés de Hoyo ◽

Borja Sañudo

Keyword(s):

Rectus Femoris ◽

Peak Torque ◽

Sprint Performance ◽

Contractile Properties ◽

Practical Significance ◽

Contraction Time ◽

Repeated Sprints ◽

Muscle Contractile Properties ◽

Repeated Sprint ◽

Muscle Contractile

Background: The present study analyzes the associations between the muscle contractile properties (MCP) measured at different neuromuscular electrical stimulation amplitudes (NMESa) and the performance or transient fatigue after a bout of repeated sprints. Methods: Seventeen physically active male subjects performed six repeated sprints of 30 m with 30 s of passive recovery. Capillary blood creatine kinase (CK) concentration, knee extension or flexion isometric peak torque, tensiomyography, and repeated sprint performance were assessed. Results: Muscle displacement and contraction time were different in relation to the NMESa used in the rectus femoris and biceps femoris muscles. At rest, significant (p < 0.05) associations were found between muscle displacement and the loss of time in the repeated sprints (sprint performance) at 20 or 40 mA in the rectus femoris. At post +24 h or +48 h, the highest significant associations were found between the muscle displacement or the contraction time and CK or peak torques also at submaximal amplitudes (20 mA). The NMESa which elicits the peak muscle displacement showed lack of practical significance. Conclusion: Although MCP are typically assessed in tensiomyography using the NMESa that elicit peak muscle displacement, a submaximal NMESa may have a higher potential practical application to assess neuromuscular fatigue in response to repeated sprints.

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