Regional changes in capillary supply in skeletal muscle of high-intensity endurance-trained rats

1996 ◽  
Vol 81 (2) ◽  
pp. 619-626 ◽  
Author(s):  
D. Gute ◽  
C. Fraga ◽  
M. H. Laughlin ◽  
J. F. Amann
Keyword(s):  
Training Program ◽  
Endurance Training ◽  
High Intensity ◽  
Gastrocnemius Muscle ◽  
Citrate Synthase ◽  
Muscle Fiber Types ◽  
Numerical Density ◽  
Image Analyzer ◽  
Fiber Types ◽  
Capillary Supply

The objective of this study was to test the hypothesis that an endurance training program designed to produce recruitment of all extensor muscle fiber types during each exercise bout would stimulate capillary angiogenesis throughout rat gastrocnemius and soleus muscles. Male Sprague-Dawley rats were exercise trained 5 days/wk for 12–14 wk with exercise bouts consisting of a combination of high intensity (32 m/min on a 15% incline) and long duration (90 min/day). On completion of high-intensity endurance training (HIET) or cage activity [sedentary (Sed)], rat hindquarters were vascularly isolated and perfusion fixed with a modified Karnovsky's fixative. Capillary supply was measured in soleus and gastrocnemius muscles by using Olympus Cue 2 image-analyzer software. Capillary supply was reflected in measurements of capillary-to-fiber ratio, capillary numerical density, capillary surface area density, and capillary volume density on transversely cut tissue sections. HIET increased citrate synthase activity by 20 and 42% in the medial and long heads of the triceps brachii, respectively. Sarcomere lengths were similar in gastrocnemius and soleus muscles of Sed and HIET rats after fixation. All four indexes of capillary supply were significantly greater throughout the gastrocnemius muscle of HIET rats compared with Sed values. The relative increase in capillarity was greater in white than in red gastrocnemius muscle of HIET rats. HIET also increased capillary supply of soleus muscle. However, only capillary numerical density was statistically greater (19%) in HIET soleus compared with Sed. These results support the hypothesis that this training program would produce an increase in capillary supply in all extensor muscles.

Influence of training on skeletal muscle enzymatic adaptations in normal and diabetic rats

1985 ◽  
Vol 249 (4) ◽  
pp. E360-E365 ◽  
Author(s):  
E. G. Noble ◽  
C. D. Ianuzzo
Keyword(s):  
Skeletal Muscle ◽  
Exercise Training ◽  
Citrate Synthase ◽  
Diabetic Rats ◽  
Muscle Fiber Types ◽  
Fiber Types ◽  
Marker Enzymes ◽  
Oxidative Potential ◽  
Hydroxyacyl Coa Dehydrogenase ◽  
Fast Twitch

Muscle homogenates representing slow-twitch oxidative, fast-twitch oxidative-glycolytic, fast-twitch glycolytic, and mixed fiber types were prepared from normal, diabetic, and insulin-treated diabetic rats. Diabetes was induced by injection of 80 mg . kg-1 of streptozotocin. The activities of citrate synthase, succinate dehydrogenase, and 3-hydroxyacyl-CoA dehydrogenase were employed as markers of oxidative potential, whereas phosphorylase, hexokinase, and phosphofructokinase activities were used as an indication of glycolytic capacity. Diabetes was associated with a general decrement in the activity of oxidative marker enzymes for all fiber types except the fast-twitch glycolytic fiber. In contrast, the fast-twitch glycolytic fibers demonstrated the greatest decline in glycolytic enzymatic activity. Insulin-treated animals, either trained or untrained, exhibited enzyme activities similar to their normal counterparts. Exercise training of diabetic rats mimicked the effect of insulin treatment and caused a near normalization of the activity of the marker enzymes. These findings suggest that the enzymatic potential of all skeletal muscle fiber types of diabetic rats may be normalized by exercise training even in the absence of significant amounts of insulin.

Endurance training, not acute exercise, differentially alters beta-receptors and cyclase in skeletal fiber types

1990 ◽  
Vol 258 (1) ◽  
pp. E71-E77 ◽  
Author(s):  
P. J. Buckenmeyer ◽  
A. H. Goldfarb ◽  
J. S. Partilla ◽  
M. A. Pineyro ◽  
E. M. Dax
Keyword(s):  
Adenylate Cyclase ◽  
Endurance Training ◽  
Acute Exercise ◽  
Cyclase Activity ◽  
Adenylate Cyclase Activity ◽  
Muscle Fiber Types ◽  
Fiber Types ◽  
Receptor Density ◽  
Binding Characteristics ◽  
Beta Receptor

beta-Adrenergic receptor binding characteristics and adenylate cyclase activity were examined in rat skeletal muscle membranes to determine if acute exercise or endurance training altered beta-receptors or adenylate cyclase activity in different muscle fiber types. Binding characteristics and adenylate cyclase activity were examined in type IIA [red fast-twitch, red vastus (RV)], type IIB [white fast-twitch, white vastus (WV)], and type I [red slow-twitch, soleus (S)] muscles. Acute exercise involved a 20-min run on a treadmill at 20 m/min and did not alter beta-receptor density or adenylate cyclase activity in any of the fiber types examined. Endurance training consisted of a progressive treadmill protocol that involved increasing intensity and duration of exercise for 18 wk. beta-Adrenergic receptor density increased in skeletal muscle fiber types primarily recruited during submaximal training (types I and IIA), whereas nonreceptor-mediated adenylate cyclase activity was altered in the three fiber types. Endurance training significantly increased beta-receptor density in RV by 25% and in S by 19% (P less than 0.05), whereas in WV beta-receptor density was not altered. Basal adenylate cyclase activity in RV was increased approximately 2.5 fold by endurance training. Nonreceptor-mediated adenylate cyclase activity, stimulated by NaF and forskolin, increased by approximately twofold in both RV and WV as a result of endurance training. The data support and extend previous observations to show greater effects of endurance training in types I and IIA fibers with respect to alterations in beta-receptor density and alterations in adenylate cyclase activity in each fiber type. Acute exercise did not alter these parameters either in trained or untrained rats.

Influences of endurance training on the ultrastructural composition of the different muscle fiber types in humans

1985 ◽  
Vol 403 (4) ◽  
pp. 369-376 ◽  
Author(s):  
Hans Howald ◽  
Hans Hoppeler ◽  
Helgard Claassen ◽  
Odile Mathieu ◽  
Reto Straub
Keyword(s):  
Endurance Training ◽  
Muscle Fiber ◽  
Muscle Fiber Types ◽  
Fiber Types

scholarly journals THE EFFECTS OF THE RESISTANCE TRAINING ON SERUM CORTISOL, IL-6, IL-8, AND TNF- α

2018 ◽  
Vol 7 (2) ◽  
pp. 15-25 ◽  
Author(s):  
Yılmaz Öztürk ◽  
Nurten DİNÇ ◽  
Selda Bereket Yücel ◽  
Fatma Taneli ◽  
Cevval Ulman ◽  
...  
Keyword(s):  
Resistance Training ◽  
Training Program ◽  
Serum Cortisol ◽  
Study Groups ◽  
Muscle Fiber Types ◽  
Fiber Types ◽  
Post Exercise ◽  
Blood Samples ◽  
Sedentary Group ◽  
Tnf Α

Objective: The purpose of this study is to investigate effects of resistance training on IL-6, IL-8, TNF-α, blood hematocrit and cortisol levels. Materials and Methods: Thirteen players from Manisa Celal Bayar University soccer team and 14 sedentary male students were used as the study subjects. The subjects, whose average age was 18-24 years old, were healthy and free of any cardiovascular diseases. Anthropometrics measurements and blood samples were obtained from all the subjects. Blood samples were obtained basal sample (before the exercise), immediately after the training program (post-exercise), and 2 hours after the training program (2h post-exercise). All subjects participated in the training program in which intensity prescribed individually in 10 different exercises; seated leg press, knee extension, knee flexion, chest press, chest flys, lat pull down, shoulder press, triceps extension, biceps curl and sit-ups. Three sets of intensity of the each exercise were arranged according to pyramidal system at 70-80 % of the each participant. The volume of resistance training was 50-60 minutes. Results: Post exercise IL-6 (p= 0,05) and IL-8 (p= 0,04) concentration of athletes were statistically lower compared to that of sedentary group. Furthermore, serum cortisol concentrations were found to be decreased in both study groups in post exercise and 2h post exercise samples compared to basal values (p<0,05). Post exercise IL-8 (p=0,04) and TNF-α (p=0,04) values of sedentary group increased significantly compared to values at 2h post exercise. Conclusion: IL-6, IL-8, and TNF-α responses to resistance training vary depending on the recruitment of different muscle fiber types by the trained individuals during the resistance training and the recovery of glycogen storage, which is found to be different from that of sedentary individuals.

Does Polarized Training Improve Performance in Recreational Runners?

2014 ◽  
Vol 9 (2) ◽  
pp. 265-272 ◽  
Author(s):  
Iker Muñoz ◽  
Stephen Seiler ◽  
Javier Bautista ◽  
Javier España ◽  
Eneko Larumbe ◽  
...  
Keyword(s):  
Training Program ◽  
Endurance Training ◽  
High Intensity ◽  
Ventilatory Threshold ◽  
Training Session ◽  
Moderate Intensity ◽  
Intervention Period ◽  
Low Intensity ◽  
Recreational Runners ◽  
The Impact

Purpose:To quantify the impact of training-intensity distribution on 10K performance in recreational athletes.Methods:30 endurance runners were randomly assigned to a training program emphasizing low-intensity, sub-ventilatory-threshold (VT), polarized endurance-training distribution (PET) or a moderately high-intensity (between-thresholds) endurance-training program (BThET). Before the study, the subjects performed a maximal exercise test to determine VT and respiratory-compensation threshold (RCT), which allowed training to be controlled based on heart rate during each training session over the 10-wk intervention period. Subjects performed a 10-km race on the same course before and after the intervention period. Training was quantified based on the cumulative time spent in 3 intensity zones: zone 1 (low intensity, <VT), zone 2 (moderate intensity, between VT and RCT), and zone 3 (high intensity, >RCT). The contribution of total training time in each zone was controlled to have more low-intensity training in PET (±77/3/20), whereas for BThET the distribution was higher in zone 2 and lower in zone 1 (±46/35/19).Results:Both groups significantly improved their 10K time (39min18s ± 4min54s vs 37min19s ± 4min42s, P < .0001 for PET; 39min24s ± 3min54s vs 38min0s ± 4min24s, P < .001 for BThET). Improvements were 5.0% vs 3.6%, ~41 s difference at post-training-intervention. This difference was not significant. However, a subset analysis comparing the 12 runners who actually performed the most PET (n = 6) and BThET (n = 16) distributions showed greater improvement in PET by 1.29 standardized Cohen effect-size units (90% CI 0.31–2.27, P = .038).Conclusions:Polarized training can stimulate greater training effects than between-thresholds training in recreational runners.

Muscle-specific regulation of the heme biosynthetic enzyme 5'-aminolevulinate synthase

1991 ◽  
Vol 261 (4) ◽  
pp. C691-C698 ◽  
Author(s):  
D. A. Essig ◽  
L. A. McNabney
Keyword(s):  
Citrate Synthase ◽  
Liver Mitochondria ◽  
Muscle Fiber Types ◽  
Fiber Types ◽  
Mrna Levels ◽  
Adult Chicken ◽  
Aminolevulinate Synthase ◽  
Chicken Muscle ◽  
Mrna Content ◽  
Specific Regulation

The induction of 5'-aminolevulinate synthase (ALV synthase) activity in adult muscle by overload occurs in the absence of proportional changes in its mRNA content. Complete interpretation of these findings is difficult because little is known of the basal regulation of ALV synthase expression in muscle. In three adult chicken muscle fiber types (n = 5 each), differences in ALV synthase activity were correlated (r greater than or equal to 0.89; P less than 0.05) to the activities of cytochrome oxidase (COX) and citrate synthase (CS) and to levels of the “liver” isoform of ALV synthase mRNA. During posthatch development, ALV synthase activity and mRNA levels (n = 3-6 per time point) also covaried with changes in COX and CS activity. The highest levels of ALV synthase mRNA in muscle are observed early in myogenesis prior to induction of COX activity. The regulation of ALV synthase is also tissue-specific because the higher basal levels of ALV synthase activity in liver mitochondria are associated with disproportionately less oxidative enzyme activity and less of the liver ALV synthase isoform mRNA than in muscle.

The effect of rowing ergometry and resistive exercise on skeletal muscle structure and function during bed rest

2014 ◽  
Vol 116 (12) ◽  
pp. 1569-1581 ◽  
Author(s):  
Felix Krainski ◽  
Jeffrey L. Hastings ◽  
Katja Heinicke ◽  
Nadine Romain ◽  
Eric L. Pacini ◽  
...  
Keyword(s):  
Skeletal Muscle ◽  
Strength Training ◽  
Short Duration ◽  
High Intensity ◽  
Bed Rest ◽  
Muscle Volume ◽  
Muscle Fiber Types ◽  
Resonance Spectroscopy ◽  
Fiber Types ◽  
Rowing Ergometry

Exposure to microgravity causes functional and structural impairment of skeletal muscle. Current exercise regimens are time-consuming and insufficiently effective; an integrated countermeasure is needed that addresses musculoskeletal along with cardiovascular health. High-intensity, short-duration rowing ergometry and supplemental resistive strength exercise may achieve these goals. Twenty-seven healthy volunteers completed 5 wk of head-down-tilt bed rest (HDBR): 18 were randomized to exercise, 9 remained sedentary. Exercise consisted of rowing ergometry 6 days/wk, including interval training, and supplemental strength training 2 days/wk. Measurements before and after HDBR and following reambulation included assessment of strength, skeletal muscle volume (MRI), and muscle metabolism (magnetic resonance spectroscopy); quadriceps muscle biopsies were obtained to assess muscle fiber types, capillarization, and oxidative capacity. Sedentary bed rest (BR) led to decreased muscle volume (quadriceps: −9 ± 4%, P < 0.001; plantar flexors: −19 ± 6%, P < 0.001). Exercise (ExBR) reduced atrophy in the quadriceps (−5 ± 4%, interaction P = 0.018) and calf muscle, although to a lesser degree (−14 ± 6%, interaction P = 0.076). Knee extensor and plantar flexor strength was impaired by BR (−14 ± 15%, P = 0.014 and −22 ± 7%, P = 0.001) but preserved by ExBR (−4 ± 13%, P = 0.238 and +13 ± 28%, P = 0.011). Metabolic capacity, as assessed by maximal O2 consumption, 31P-MRS, and oxidative chain enzyme activity, was impaired in BR but stable or improved in ExBR. Reambulation reversed the negative impact of BR. High-intensity, short-duration rowing and supplemental strength training effectively preserved skeletal muscle function and structure while partially preventing atrophy in key antigravity muscles. Due to its integrated cardiovascular benefits, rowing ergometry could be a primary component of exercise prescriptions for astronauts or patients suffering from severe deconditioning.

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