scholarly journals Responses of Skeletal Muscle Hypertrophy in Wistar Rats to Different Resistance Exercise Models

2017 ◽  
pp. 317-323 ◽  
Author(s):  
T. F. LUCIANO ◽  
S. O. MARQUES ◽  
B. L. PIERI ◽  
D. R. DE SOUZA ◽  
L. V. ARAÚJO ◽  
...  
Keyword(s):  
Resistance Training ◽  
Resistance Exercise ◽  
Wistar Rats ◽  
Quadriceps Muscle ◽  
Cross Sectional ◽  
Skeletal Muscle Hypertrophy ◽  
Mtor Phosphorylation ◽  
Male Wistar Rats ◽  
Muscle Cross Sectional Area ◽  
Upstream Control

This study aimed to compare the effects of three different resistance exercise models on the quadriceps muscle cross-sectional area, as well as on mTOR phosphorylation and other pivotal molecules involved in the upstream regulation of mTOR. Twenty-four male Wistar rats were divided into untrained (control), endurance resistance training, strength resistance training, and hypertrophy resistance training (HRT) groups (n=6). After 12 weeks of training, the red portion of the quadriceps was removed for histological and Western blot analyses. The results showed that the quadriceps weight and cross-sectional areas in the exercised groups were higher than those of the untrained rats. However, the HRT group presented better results than the other two experimental groups. This same pattern was observed for mTOR phosphorylation and for the most pivotal molecules involved in the upstream control of mTOR (increase of PKB, 14-3-3, ERK, p38 MAPK, and 4E-BP1 phosphorylation, and reduction of tuberin, sestrin 2, REDD1, and phospho AMPK). In summary, our study showed that HRT leads to high levels of mTOR phosphorylation as well as of other proteins involved in the upstream regulation of mTOR.

Early resistance training-induced increases in muscle cross-sectional area are concomitant with edema-induced muscle swelling

2015 ◽  
Vol 116 (1) ◽  
pp. 49-56 ◽  
Author(s):  
Felipe Damas ◽  
Stuart M. Phillips ◽  
Manoel E. Lixandrão ◽  
Felipe C. Vechin ◽  
Cleiton A. Libardi ◽  
...  
Keyword(s):  
Resistance Training ◽  
Cross Sectional Area ◽  
Sectional Area ◽  
Cross Sectional ◽  
Muscle Cross Sectional Area

scholarly journals Evaluation of Rat Muscle Structure in Pre-Menopausal Period after Regular Resistance Exercise and Taking Vitamin D and Calcium Supplements

2020 ◽  
Author(s):  
Seyedeh Zahra Hosseini Sisi ◽  
Mohammad Ali Azarbayjani ◽  
Mohammad Reza Vafaeenasab ◽  
Maghsoud Peeri ◽  
Mohammad Reza Dehghani
Keyword(s):  
Vitamin D ◽  
Resistance Training ◽  
Resistance Exercise ◽  
Muscle Fiber ◽  
Wistar Rats ◽  
Fiber Diameter ◽  
Inflammatory Cells ◽  
Control Group ◽  
Standard Diet ◽  
Calcium Supplements

Introduction: Menopause can change the musculoskeletal system by reducing estrogen hormone levels. The aim of this study was to evaluate the effect of regular resistance training accompanied by vitamins D and calcium supplements during pre-menopausal period on muscle tissues of Wistar rats’ postmenopausal period. Methods: In this experimental study, female Wistar rats were randomly divided into control, placebo, vitamins D, Calcium, excercise, vitamins D- Calcium, vitamins.D- excercise, Calcium - excercise, and vitamins.D‐ Calcium - excercise groups. Control and placebo groups were fed with a standard diet and sesame oil, respectively. The amount of calcium consumed was 35 mg / kg and the amount of vitamin D was 10000 IU during the two-month period, and in the resistance training groups, two months of training was performed with a ladder. Then ovariectomy was done and sample of the gastrocnemius muscle was taken and the diameter of muscle fiber, the number of muscle and adipocyte cell as well as the number of inflammatory cells were studied. The statistical analysis by means of one-way ANOVA and SPSS version 20 was performed. Results: Compared to the control group, the increase in the number of adipocyte cells were observed in the vitamin D, calcium-vitamin D, vitamin D-resistance exercise and placebo groups but it was not significantly different. Muscle fiber diameter significantly increased in all groups compared to the control group (P <0.001). The number of muscle cells increased significantly in the calcium-resistance exercise group (103± 9), vitamin D-resistance exercise (105 ±6.9) and calcium-vitamin D-resistance exercise (114 ± 3.16) compared to the control group, while, there was a significant increase in inflammatory cells only in the control and placebo groups (p≤0.05). Conclusion: Regular resistance exercise accompanied with vitamin D and Calcium supplements in premenopausal period can improve muscle fiber diameter and muscle cell numbers; in addition, the process of decrease in the muscle strength and muscle inflammation during menopause will be delayed.

Effect of Subcutaneous Tissue on Changes in Thigh Circumference Following Anterior Cruciate Ligament Reconstruction

2019 ◽  
Vol 40 (08) ◽  
pp. 544-550
Author(s):  
Ryo Yoshii ◽  
Yu Konishi ◽  
Daisuke Ando ◽  
Satoshi Ochiai ◽  
Tetsuo Hagino ◽  
...  
Keyword(s):  
Subcutaneous Tissue ◽  
Cruciate Ligament ◽  
Subcutaneous Fat ◽  
Quadriceps Muscle ◽  
Thigh Circumference ◽  
Cross Sectional ◽  
Short Period ◽  
Anterior Cruciate ◽  
Muscle Cross Sectional Area ◽  
The Relationship

AbstractCircumference measurements have been used to estimate muscle cross-sectional area (CSA) in clinical settings. Measurements of thigh circumference are affected by muscle and subcutaneous fat (SF). In fact, SF could increase over a short period. Therefore, clarifying the relationship between thigh circumference and muscle and SF following ACL reconstruction is important. This study’s primary purpose was to examine pre- and post-operative changes in thigh circumference, thigh muscles and SF CSAs in both legs. Secondary, the relationship between thigh circumference and muscle and SF CSAs was examined to demonstrate that circumference measurements could be used to detect atrophy. Quadriceps, hamstrings, and SF CSAs at 15, 10, and 5 cm proximal to the patella were measured by MRI pre- and 4 weeks postoperatively to examine how reconstruction affected those tissues in the thighs. The results showed increases in SF CSA (r=0.72 at 10 cm, r=0.67 at 15 cm) greatly affected thigh circumference in females on the surgical side. In males, increases in SF CSA (r=0.83) at 15- and 5-cm and decreases in quadriceps muscle CSA (r=0.73) at 5 cm affected thigh circumference on the surgical side. Thigh circumference measurements might not reflect actual muscle CSA in ACL patients.

Changes in the human muscle force-velocity relationship in response to resistance training and subsequent detraining

2005 ◽  
Vol 99 (1) ◽  
pp. 87-94 ◽  
Author(s):  
Lars L. Andersen ◽  
Jesper L. Andersen ◽  
S. Peter Magnusson ◽  
Charlotte Suetta ◽  
Jørgen L. Madsen ◽  
...  
Keyword(s):  
Resistance Training ◽  
Knee Extension ◽  
Limb Movement ◽  
Cross Sectional Area ◽  
Contractile Properties ◽  
Type I ◽  
Maximal Velocity ◽  
Sectional Area ◽  
Cross Sectional ◽  
Muscle Cross Sectional Area

Previous studies show that cessation of resistance training, commonly known as “detraining,” is associated with strength loss, decreased neural drive, and muscular atrophy. Detraining may also increase the expression of fast muscle myosin heavy chain (MHC) isoforms. The present study examined the effect of detraining subsequent to resistance training on contractile performance during slow-to-medium velocity isokinetic muscle contraction vs. performance of maximal velocity “unloaded” limb movement (i.e., no external loading of the limb). Maximal knee extensor strength was measured in an isokinetic dynamometer at 30 and 240°/s, and performance of maximal velocity limb movement was measured with a goniometer during maximal unloaded knee extension. Muscle cross-sectional area was determined with MRI. Electromyographic signals were measured in the quadriceps and hamstring muscles. Twitch contractions were evoked in the passive vastus lateralis muscle. MHC isoform composition was determined with SDS-PAGE. Isokinetic muscle strength increased 18% ( P < 0.01) and 10% ( P < 0.05) at slow and medium velocities, respectively, along with gains in muscle cross-sectional area and increased electromyogram in response to 3 mo of resistance training. After 3 mo of detraining these gains were lost, whereas in contrast maximal unloaded knee extension velocity and power increased 14% ( P < 0.05) and 44% ( P < 0.05), respectively. Additionally, faster muscle twitch contractile properties along with an increased and decreased amount of MHC type II and MHC type I isoforms, respectively, were observed. In conclusion, detraining subsequent to resistance training increases maximal unloaded movement speed and power in previously untrained subjects. A phenotypic shift toward faster muscle MHC isoforms (I → IIA → IIX) and faster electrically evoked muscle contractile properties in response to detraining may explain the present results.

UPPER BODY RESISTANCE TRAINING IN WOMEN INCREASES ARM MUSCLE CROSS-SECTIONAL AREA BY A 20% AVERAGE

1999 ◽  
Vol 31 (Supplement) ◽  
pp. S325
Author(s):  
L. A. Gotshalk ◽  
B. C. Nindl ◽  
R. U. Newton ◽  
S. J. Fleck ◽  
K. H??kkinen ◽  
...  
Keyword(s):  
Resistance Training ◽  
Cross Sectional Area ◽  
Upper Body ◽  
Sectional Area ◽  
Cross Sectional ◽  
Body Resistance ◽  
Muscle Cross Sectional Area

Skeletal muscle adaptations to testosterone and resistance training in men with COPD

2007 ◽  
Vol 103 (4) ◽  
pp. 1299-1310 ◽  
Author(s):  
Michael I. Lewis ◽  
Mario Fournier ◽  
Thomas W. Storer ◽  
Shalender Bhasin ◽  
Janos Porszasz ◽  
...  
Keyword(s):  
Resistance Training ◽  
Respir Crit ◽  
Quadriceps Muscle ◽  
Chronic Obstructive ◽  
Fiber Density ◽  
Mrna Isoforms ◽  
Related Factors ◽  
Cross Sectional ◽  
Obstructive Pulmonary Disease ◽  
Protein Levels

We recently reported increased leg lean mass and strength in men with chronic obstructive pulmonary disease (COPD) receiving 10 wk of testosterone (T) and leg resistance training (R) (Casaburi R, Bhasin S, Cosentino L, Porszasz J, Somfay A, Lewis M, Fournier M, Storer T. Am J Respir Crit Care Med 170: 870–878, 2004). The present study evaluates the role of muscle IGF and related factors as potential mechanisms for our findings, using quadriceps muscle biopsies from the same cohort. Patient groups were 1) weekly placebo (P) injections + no R; 2) P and R; 3) weekly injections of T + no R; and 4) T + R (TR). Muscle fibers were classified histochemically, and their cross-sectional areas (CSAs) and fiber density (number of fibers per unit area) were determined. Gene transcripts were determined by real-time PCR and protein expression by RIA. While no significant changes in fiber CSAs were noted across groups, increased trends were observed after 10 wk, and significant decrements in muscle fiber density were noted in all treated groups. A global increase in all myosin heavy chain (MyHC) mRNA isoforms was observed in TR patients. Muscle IGF-IEa and IGF-IEc mRNAs were significantly increased with TR group. Muscle IGF-I protein was increased in all intervention groups (greatest in TR). While TR IGF-II mRNA was increased, protein levels were unaltered. IGF binding protein-4 mRNA was increased with TR. Myogenin mRNA was increased in both T groups, while MyoD and myostatin were unchanged. Muscle atrophy F-box mRNA tended to increase with TR. Our data suggest that the combined interventions produced an enhanced local anabolic milieu driven in large part by the muscle IGF system, despite potentially negative biochemical influences present in COPD patients.

scholarly journals Effect of Resistance Exercise and Vitamin C Intake on Expression of Telomerase Reverse Transcriptase and Telomere Repeat Binding Factor-2 Genes and the Diameter and Number of Myofibrils in Old Rats

2021 ◽  
Vol 10 (4) ◽  
pp. 396-409
Author(s):  
Yousef Shirkhani ◽  
◽  
Maghsoud Peeri ◽  
Mohammad Ali Azarbayjani ◽  
Hassan Matinhomaee ◽  
...  
Keyword(s):  
Skeletal Muscle ◽  
Vitamin C ◽  
Resistance Exercise ◽  
Wistar Rats ◽  
Telomere Repeat ◽  
Vitamin Intake ◽  
Binding Factor ◽  
Male Wistar Rats ◽  
Old Rats ◽  
The Difference

Objective: Cell aging is one of the most important and fundamental step in cellular behavior and reduces muscle mass and myofibrils. This study aims to investigate the effect of resistance exercise along with vitamin C consumption on the expression of Telomerase Reverse Transcriptase (TERT) and Telomere Repeat Binding Factor-2 (TRF2) genes and the diameter and number of skeletal muscle myofibrils in old male Wistar rats. Methods: This is an experimental study using control groups. Twenty-five male Wistar rats (280-320 g and aged 24 weeks) were randomly divided into five groups of young control, old+resistance exercise, old+vitamin intake, old+resistance exercise+vitamin intake, and old control. In the supplementation groups, rats received liposomal vitamin C daily by gavage per body weight. Weight attached to the tail gradually increased during 8 weeks of exercise (weeks 1 and 2 by 50%; weeks 3 and 4 by 50%; weeks 5 and 6 by 75%; weeks 7 and 8 by 100% of total body weight). Exercises were performed at 3-5 sets of 8-12 repetitions, 3 or 4 days a week. The Quantitative polymerase chain reaction method was used to evaluate the expression of TERT and TRF2 genes in muscle tissue. One-way ANOVA was used to examine the difference between the groups and Tukey’s post hoc test was used to determine between which groups the difference was significant. Results: Aging significantly reduced the expression of TERT, TRF2 genes and the diameter and number of myofibrils in skeletal muscle of rats (P=0.001). Resistance exercise along with vitamin C intake had no significant effect on TERT and TRF2 expression (P≥0.05), but caused a significant increase in the diameter and number of myofibrils (P= 0.001). Conclusion: Eight weeks of resistance exercise along with vitamin C supplementation can significantly increase the number and diameter of skeletal muscle myofibrils in old rats.

Sign in / Sign up

Export Citation Format

Share Document