Cross-adaptive responses to different forms of leg training: skeletal muscle biochemistry and histochemistry

The influence of a program of high intensity training and of a combined program of high intensity training and prolonged submaximal training on adaptations to the vastus lateralis muscle was investigated in two groups of elite athletes. The high intensity training (HI) consisted of ice hockey practices and games over a 14-week period while the combined program (HI–LO) included the addition of supplementary sessions of cycling, three times per week, progressively increasing from 30 to 45 min per session and at an intensity of 70% [Formula: see text]. Determinations of enzyme activities representative of energy supplying pathways revealed no change in 3-hydroxyacl CoA dehydrogenase (HADH), total phosphorylase (PHOSP), phosphofructokinase (PFK), lactate dehydrogenase (LDH), and a 7% increase (p < 0.05) in succinate dehydrogenase (SDH). The addition of the supplementary program caused no further adaptation in the metabolic profile. Similarly, neither the HI nor the HI–LO program induced any alteration in the percentage fibre type (slow twitch (ST) vs. fast twitch (FT)) or the subtypes (FTa, FTb, FTc). Reductions in the size (p < 0.05) of ST fibres were noted for both the HI and the HI–LO training programs. In contrast, increases in capillarization (p < 0.05) were found for both the ST (23%) and FTa (32%) fibres for the HI–LO program whereas a reduction in capillarization (21%) occurred in the FTa fibres as a result of HI training only. It is concluded that metabolic differentiation does not appear to occur in a manner consistent with the conditions of energy expenditure at least for high intensity work.

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Enhanced sarcoplasmic reticulum Ca2+ release following intermittent sprint training

AJP Regulatory Integrative and Comparative Physiology ◽

10.1152/ajpregu.2000.279.1.r152 ◽

2000 ◽

Vol 279 (1) ◽

pp. R152-R160 ◽

Cited By ~ 49

Author(s):

Niels Ørtenblad ◽

Per K. Lunde ◽

Klaus Levin ◽

Jesper L. Andersen ◽

Preben K. Pedersen

Keyword(s):

Sarcoplasmic Reticulum ◽

High Intensity ◽

Vastus Lateralis ◽

Ryanodine Receptors ◽

Vastus Lateralis Muscle ◽

Sprint Training ◽

High Intensity Training ◽

Before And After ◽

Muscle Biopsies ◽

Intensity Training

To evaluate the effect of intermittent sprint training on sarcoplasmic reticulum (SR) function, nine young men performed a 5 wk high-intensity intermittent bicycle training, and six served as controls. SR function was evaluated from resting vastus lateralis muscle biopsies, before and after the training period. Intermittent sprint performance (ten 8-s all-out periods alternating with 32-s recovery) was enhanced 12% ( P < 0.01) after training. The 5-wk sprint training induced a significantly higher ( P < 0.05) peak rate of AgNO3-stimulated Ca2+ release from 709 (range 560–877; before) to 774 (596–977) arbitrary units Ca2+ ⋅ g protein− 1 ⋅ min− 1(after). The relative SR density of functional ryanodine receptors (RyR) remained unchanged after training; there was, however, a 48% ( P < 0.05) increase in total number of RyR. No significant differences in Ca2+ uptake rate and Ca2+-ATPase capacity were observed following the training, despite that the relative density of Ca2+-ATPase isoforms SERCA1 and SERCA2 had increased 41% and 55%, respectively ( P < 0.05). These data suggest that high-intensity training induces an enhanced peak SR Ca2+ release, due to an enhanced total volume of SR, whereas SR Ca2+ sequestration function is not altered.

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Moderate-intensity Versus High-intensity Training On Glutathione System In Slow-twitch And Fast-twitch Muscles Of Diabetic Rats

Medicine & Science in Sports & Exercise ◽

10.1249/01.mss.0000764692.97839.34 ◽

2021 ◽

Vol 53 (8S) ◽

pp. 467-467

Author(s):

Jesús D. Álvarez-Almeyda ◽

Margarita Muñoz-Guevara ◽

Sarai Sánchez-Duarte ◽

Sergio Márquez-Gamiño ◽

Karla S. Vera-Delgado ◽

...

Keyword(s):

High Intensity ◽

Diabetic Rats ◽

Moderate Intensity ◽

Glutathione System ◽

High Intensity Training ◽

Slow Twitch ◽

Fast Twitch ◽

Intensity Training

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Histochemical characteristics of human expiratory and inspiratory intercostal muscles

Journal of Applied Physiology ◽

10.1152/jappl.1989.67.2.592 ◽

1989 ◽

Vol 67 (2) ◽

pp. 592-598 ◽

Cited By ~ 35

Author(s):

M. Mizuno ◽

N. H. Secher

Keyword(s):

Vastus Lateralis ◽

Vastus Lateralis Muscle ◽

Post Mortem ◽

Intercostal Muscles ◽

Relative Occurrence ◽

Lateralis Muscle ◽

Fiber Size ◽

Slow Twitch ◽

Fast Twitch ◽

Healthy Males

The relative occurrence of slow-twitch (ST) and fast-twitch (FTa and FTb) fibers, fiber size, and capillary supply in internal (INT) and external intercostal muscles (EXT), the costal diaphragm (DIA), and vastus lateralis muscle (VAS) was examined post-mortem in eight healthy males. The relative occurrence of ST fibers in INT [64 +/- 3% (SE)] and EXT (62 +/- 3%) was similar but higher than in DIA (49 +/- 3%) and VAS (40 +/- 6%; P less than 0.05). The occurrence of FTa fibers in expiratory INT (35 +/- 3%) was higher than in inspiratory INT and EXT (17 +/- 1%; P less than 0.05) but similar to DIA (28 +/- 6%) and VAS (32 +/- 2%). Accordingly, expiratory INT had fewer FTb fibers (1 +/- 1%) than the others (P less than 0.05). Expiratory INT had a 60% larger fiber area than inspiratory INT and EXT and DIA (P less than 0.05), but the area was similar to that of VAS. The number of capillaries per fiber was higher in expiratory INT (2.3 +/- 0.1) than in inspiratory INT and EXT (1.6 +/- 0.1), DIA (1.9 +/- 0.1), and VAS (1.8 +/- 0.2; P less than 0.05). The results suggest that the occurrence of many large capillary-rich FTa fibers in expiratory INT is bound to function (expiratory vs. inspiratory) rather than to anatomy (INT vs. EXT).

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Effects of Moderate- and High-Intensity Chronic Exercise on the Adiponectin Levels in Slow-Twitch and Fast-Twitch Muscles in Rats

Medicina ◽

10.3390/medicina55060291 ◽

2019 ◽

Vol 55 (6) ◽

pp. 291 ◽

Cited By ~ 1

Author(s):

Jiménez-Maldonado ◽

Virgen-Ortiz ◽

Lemus ◽

Castro-Rodríguez ◽

Cerna-Cortés ◽

...

Keyword(s):

Physical Exercise ◽

High Intensity ◽

Skeletal Muscles ◽

Adiponectin Receptor ◽

Chronic Exercise ◽

Adiponectin Receptor 1 ◽

Obesity And Diabetes ◽

Slow Twitch ◽

Fast Twitch ◽

Intensity Training

Background and objectives: Adipose tissue and skeletal muscle secrete adiponectin, a hormone abundantly secreted by adipocytes, that through the adiponectin receptor, regulate glucose and lipid metabolism. Adiponectin appears to protect skeletal muscles from inflammatory damage induced by oxidative stress. It has been suggested that decreased adiponectin levels could be associated with pathologic conditions, including obesity and diabetes. Furthermore, some studies suggest that exercise could have a beneficial effect by increasing adiponectin levels, but this observation remains controversial. It is also unknown if physical exercise modifies adiponectin expression in skeletal muscles. The aim of this study was to investigate the effect of chronic exercise on serum adiponectin and adiponectin expression in slow-twitch (soleus) and fast-twitch (plantaris) muscles in healthy rats. Materials and methods: Two-month-old male Wistar rats were randomly divided into three groups with n = 6 in each group: control (C), moderate-intensity training (MIT), and high-intensity training (HIT). The rats were conditioned to run on a treadmill for the 8-week period. Forty-eight hours after the last session, blood samples were collected for adiponectin measurements and total RNA was isolated from plantaris and soleus muscles to measure by RT-qPCR adiponectin receptor 1 and adiponectin mRNA expression level. Results: MIT and HIT groups had reduced adiponectin protein levels in serum and the plantaris muscle, but not changes in adiponectin protein were observed in the soleus muscle. No significant differences in Adiponectin receptor 1 (AdipoR1) gene expression were observed following intense or moderate exercise in either muscle group studied. Conclusions: Our study shows that decreasing levels of circulating adiponectin is a result of physical exercise and should not be generalized as a predictive marker of disease.

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Buffering capacity of deproteinized human vastus lateralis muscle

Journal of Applied Physiology ◽

10.1152/jappl.1985.58.1.14 ◽

1985 ◽

Vol 58 (1) ◽

pp. 14-17 ◽

Cited By ~ 114

Author(s):

W. S. Parkhouse ◽

D. C. McKenzie ◽

P. W. Hochachka ◽

W. K. Ovalle

Keyword(s):

High Intensity ◽

Buffer Capacity ◽

Vastus Lateralis ◽

Staining Intensity ◽

Vastus Lateralis Muscle ◽

Lateralis Muscle ◽

Ph Range ◽

Buffer Capacities ◽

Fast Twitch

The in vitro deproteinized vastus lateralis muscle buffer capacity, carnosine, and histidine levels were examined in 20 men from 4 distinct populations (5 sprinters, 800-m runners; 5 rowers; 5 marathoners; 5 untrained). Needle biopsies were obtained at rest from the vastus lateralis muscle. The buffer capacity was determined in deproteinized homogenates by repeatedly titrating supernatant extracts over the pH range of 7.0–6.0 with 0.01 N HCl. Carnosine and histidine levels were determined on an amino acid AutoAnalyzer. Fast-twitch fiber percentage was determined by staining intensity of myosin adenosinetriphosphatase. High-intensity running performance was assessed on an inclined treadmill run to fatigue (20% incline; 3.5 m X s-1). Significantly (P less than 0.01) elevated buffer capacities, carnosine levels, and high-intensity running performances were demonstrated by the sprinters and rowers, but no significant differences existed between these variables for the marathoners vs. untrained subjects. Low but significant (P less than 0.05) interrelationships were demonstrated between buffer capacity, carnosine levels, and fast-twitch fiber composition. These findings indicate that the sprinters and rowers possess elevated buffering capabilities and carnosine levels compared with marathon runners and untrained subjects.

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