Muscle fiber size increases following resistance training in multiple sclerosis

2010 ◽  
Vol 16 (11) ◽  
pp. 1367-1376 ◽  
Author(s):  
U Dalgas ◽  
E Stenager ◽  
J Jakobsen ◽  
T Petersen ◽  
K Overgaard ◽  
...  

Objective: To test the hypothesis that lower body progressive resistance training (PRT) leads to an increase of the muscle fiber cross-sectional area (CSA) and a shift in the proportion of fiber types in patients with multiple sclerosis (MS). Methods: The present study was a two-arm, randomized controlled trial (RCT). Thirty-eight MS patients (Expanded Disability Status Scale (EDSS) 3—5.5) were randomized to a PRT group (Exercise, n = 19) or a control group (Control, n = 19). The Exercise group performed a biweekly 12-week lower body PRT program [five exercises progressing from 15RM (Repetition Maximum) towards 8RM], whereas the Control group maintained their usual daily activity level during the trial period. Muscle biopsies from vastus lateralis were taken before (pre) and after the trial (post). Thigh volume (TV) was estimated from anthropometric measurements. Isokinetic muscle strength of the knee extensors (KE) and flexors (KF) were evaluated at slow (90°/s) and fast (180°/s) angular velocities. Results: In the Exercise group the mean CSA of all muscle fibers (7.9 ± 15.4% vs. -3.5 ± 9.0%, p = 0.03) and of type II muscle fibers (14.0 ± 19.4% vs. -2.6 ± 15.5%, p = 0.02) increased in comparison with the Control group. No changes occurred in the proportion of fiber types in the Exercise group. Neither was there any change in total TV. Isokinetic strength at KE180, KF90 and KF180 improved significantly after PRT when compared with the control group (10.2—21.3%, p ≤ 0.02). Conclusions: We conclude that progressive resistance training induces a compensatory increase of muscle fiber size in patients with the central nervous system disorder, multiple sclerosis.

2010 ◽  
Vol 16 (4) ◽  
pp. 480-490 ◽  
Author(s):  
U. Dalgas ◽  
E. Stenager ◽  
J. Jakobsen ◽  
T. Petersen ◽  
HJ Hansen ◽  
...  

Fatigue occurs in the majority of multiple sclerosis patients and therapeutic possibilities are few. Fatigue, mood and quality of life were studied in patients with multiple sclerosis following progressive resistance training leading to improvement of muscular strength and functional capacity. Fatigue (Fatigue Severity Scale, FSS), mood (Major Depression Inventory, MDI) and quality of life (physical and mental component scores, PCS and MCS, of SF36) were scored at start, end and follow-up of a randomized controlled clinical trial of 12 weeks of progressive resistance training in moderately disabled (Expanded Disability Status Scale, EDSS: 3—5.5) multiple sclerosis patients including a Control group ( n = 15) and an Exercise group ( n = 16). Fatigue (FSS > 4) was present in all patients. Scores of FSS, MDI, PCS—SF36 and MCS—SF36 were comparable at start of study in the two groups. Fatigue improved during exercise by —0.6 (95% confidence interval (CI) —1.4 to 0.4) a.u. vs. 0.1 (95% CI —0.4 to 0.6) a.u. in controls ( p = 0.04), mood improved by —2.4 (95% CI —4.1 to 0.7) a.u. vs. 1.1 (—1.2 to 3.4) a.u. in controls ( p = 0.01) and quality of life (PCS—SF36) improved by 3.5 (95% CI 1.4—5.7) a.u. vs. —1.0 (95% CI —3.4—1.4) a.u. in controls ( p = 0.01). The beneficial effect of progressive resistance training on all scores was maintained at follow-up after further 12 weeks. Fatigue, mood and quality of life all improved following progressive resistance training, the beneficial effect being maintained for at least 12 weeks after end of intervention.


2019 ◽  
Vol 44 (11) ◽  
pp. 1159-1164 ◽  
Author(s):  
Chad W. Wagoner ◽  
Erik D. Hanson ◽  
Eric D. Ryan ◽  
Ryan Brooks ◽  
William A. Wood ◽  
...  

It is not uncommon for sedentary individuals to cite leg fatigue as the primary factor for test termination during a cardiopulmonary exercise test (CPET) on a cycle ergometer. The purpose of this study was to examine the effect of 2 weeks of lower body resistance training (RT) on cardiopulmonary capacity in sedentary middle-aged females. Additionally, the impact of RT on muscle strength was evaluated. Following familiarization, 28 women (18 exercise group, 10 control group) completed a maximal CPET on a cycle ergometer to determine peak oxygen uptake and leg extensor strength assessed using isokinetic dynamometry. Participants in the exercise group performed 2 weeks (6 sessions) of lower body RT, which comprised leg press, leg curl, and leg extension exercises. A 2-way repeated-measures ANOVA was used to evaluate the difference in changes of peak oxygen uptake and peak torque (PT). Peak oxygen uptake significantly improved from 22.2 ± 4.5 mL·kg−1·min−1 to 24.3 ± 4.4 mL·kg−1·min−1 (10.8%, p < 0.05) as well as PT from 83.1 ± 25.4 Nm to 89.0 ± 29.7 Nm (6.1%, p < 0.05) in the exercise group with no change in the control group. These findings provide initial evidence that 2 weeks of lower body RT prior to a CPET may be a helpful preconditioning strategy to achieve a more accurate peak oxygen uptake during testing, enhancing tolerability to a CPET by improving lower body strength.


2019 ◽  
Vol 2 (2) ◽  
pp. 67-68
Author(s):  
Anusha Sivakumar ◽  
Patience Coleman ◽  
Bimol C Roy ◽  
Heather L Bruce

The muscle fibers that have been examined in the study were affected by three different controlled factors: steroids, ractopamine and residual feed intake (RFI). By examining the effects of the controlled factors on cattle’s muscle fibers, it can be determined if they affect different meat properties, such as meat toughness, collagen solubility and muscle fiber quality. The research had been done specifically with m. semimembranosus (SM) of crossbred steers. Although some may be concerned with the health effects of steroids and other materials, no negative effects to the health of the cattle were observed after the use of steroids. This is because the hormones being introduced into the cattle’s body already exist in the animal. In addition, the same concept applies to humans who consume the meat, preventing harm the people who consume it. For this study, 48 crossbred angus steers were used, 12 for each of the different treatment groups. The control group consisted of no steroids and no ractopamine. The second group was not treated with steroid but with ractopamine. The third group was treated with steroids but no ractopamine. Finally, the fourth group was treated with both, the steroids and the ractopamine. For each SM muscle, 1-inch thick steaks were cut and from those steaks, 1cm3 cubes were cut. These cubes were frozen in dry ice acetone until they are ready to be sectioned. Cubes are placed in the cryostat and sliced into serial sections of 10µm. These serial sections are then mounted onto dry slide glass and stored in a freezer at -80ºC until they are to be stained. The staining process helps to identify the different types of muscle fibers in the samples. From the muscle fiber types, the average sizes of each muscle fiber is calculated to identify inconsistencies among the different treatment groups. Conclusions will be drawn based on the inconsistencies found (if any).


2007 ◽  
Vol 125 (1) ◽  
pp. 22-28 ◽  
Author(s):  
Claudio Battaglini ◽  
Martim Bottaro ◽  
Carolyn Dennehy ◽  
Logan Rae ◽  
Edgar Shields ◽  
...  

CONTEXT AND OBJECTIVE: Changes in metabolism have been reported in the majority of patients undergoing cancer treatment, and these are usually characterized by progressive change in body composition. The effects of aerobic exercise programs to combat the cancer and cancer treatment-related side effects, which include the negative changes in body composition, have been extensively reported in the literature. However, few resistance exercise intervention studies have hypothesized that breast cancer patients might benefit from this type of exercise. The purpose of this study was to determine whether exercise protocols that emphasize resistance training would change body composition and strength in breast cancer patients undergoing treatment. DESIGN AND SETTING: Randomized controlled trial, at the Campus Recreation Center and Rocky Mountain Cancer Rehabilitation Institute of the University of Northern Colorado, and the North Colorado Medical Center. METHODS: Twenty inactive breast cancer patients were randomly assigned to a 21-week exercise group (n = 10) or a control group (n = 10). The exercise group trained at low to moderate intensity for 60 minutes on two days/week. The primary outcome measurements included body composition (skinfold method) and muscle strength (one repetition maximum). RESULTS: Significant differences in lean body mass, body fat and strength (p = 0.004, p = 0.004, p = 0.025, respectively) were observed between the groups at the end of the study. CONCLUSION: The results suggest that exercise emphasizing resistance training promotes positive changes in body composition and strength in breast cancer patients undergoing treatment.


Author(s):  
Jennifer E. Gilda ◽  
Joon-Hyuk Ko ◽  
Aviv-Yvonne Elfassy ◽  
Nadav Tropp ◽  
Anna Parnis ◽  
...  

The size and shape of skeletal muscle fibers are affected by various physiological and pathological conditions, such as muscle atrophy, hypertrophy, regeneration, and dystrophies. Hence, muscle fiber cross-sectional area (CSA) is an important determinant of muscle health and plasticity. We adapted the Imaris software to automatically segment muscle fibers based on fluorescent labeling of the plasma membrane, and measure muscle fiber CSA. Analysis of muscle cross sections by the Imaris semi-automated and manual approaches demonstrated a similar decrease in CSA of atrophying muscles from fasted mice compared with fed controls. In addition, we previously demonstrated that downregulation of the Ca2+-specific protease calpain-1 attenuates muscle atrophy. Accordingly, both the Imaris semi-automated and manual approaches showed a similar increase in CSA of fibers expressing calpain-1 shRNA compared with adjacent non-transfected fibers in the same muscle cross section. Although both approaches seem valid for measurements of muscle fiber size, the manual marking method is less preferable because it is highly time-consuming, subjective, and limits the number of cells that can be analyzed. The Imaris semi-automated approach is user-friendly, requires little training or optimization, and can be used to efficiently and accurately mark thousands of fibers in a short period of time. As a novel addition to the commonly used statistics, we also describe statistical tests that quantify the strength of an effect on fiber size, enabling detection of significant differences between skewed distributions that would otherwise not be detected using typical methods.


1991 ◽  
Vol 71 (4) ◽  
pp. 1589-1592 ◽  
Author(s):  
G. R. Chalmers ◽  
R. R. Roy ◽  
V. R. Edgerton

To determine the level of coordination in succinate dehydrogenase (SDH) activity between plantaris motoneurons and muscle fibers, the soleus and gastrocnemius muscles were bilaterally excised in four cats to subject the plantaris to functional overload (FO). Five normal cats served as controls. Twelve weeks after surgery the right plantaris in each cat was injected with horseradish peroxidase to identify plantaris motoneurons. SDH activity then was measured in a population of plantaris motoneurons and muscle fibers in each cat. Control motoneurons and muscle fibers had similar mean SDH activities and a similar relationship between cell size and SDH activity. After FO, muscle fiber size doubled and mean muscle fiber SDH activity halved. Motoneuron mean SDH activity and size were unaffected by FO. Total SDH activity was unchanged in both the motoneurons and muscle fibers after FO. These changes suggest a selective increase in contractile proteins with little or no modulation of mitochondrial proteins in the muscle fibers, because total SDH activity was unchanged in muscle fibers after FO. These data demonstrate that although mean SDH activities were similar in control motoneurons and muscle fibers, mean SDH activities in these two cell types can change independently.


Author(s):  
Seyedeh Zahra Hosseini Sisi ◽  
Mohammad Ali Azarbayjani ◽  
Mohammad Reza Vafaeenasab ◽  
Maghsoud Peeri ◽  
Mohammad Reza Dehghani

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.


2016 ◽  
Vol 48 (9) ◽  
pp. 699-710 ◽  
Author(s):  
Robert Güth ◽  
Alexander Chaidez ◽  
Manoj P. Samanta ◽  
Graciela A. Unguez

Skeletal muscle is distinguished from other tissues on the basis of its shape, biochemistry, and physiological function. Based on mammalian studies, fiber size, fiber types, and gene expression profiles are regulated, in part, by the electrical activity exerted by the nervous system. To address whether similar adaptations to changes in electrical activity in skeletal muscle occur in teleosts, we studied these phenotypic properties of ventral muscle in the electric fish Sternopygus macrurus following 2 and 5 days of electrical inactivation by spinal transection. Our data show that morphological and biochemical properties of skeletal muscle remained largely unchanged after these treatments. Specifically, the distribution of type I and type II muscle fibers and the cross-sectional areas of these fiber types observed in control fish remained unaltered after each spinal transection survival period. This response to electrical inactivation was generally reflected at the transcript level in real-time PCR and RNA-seq data by showing little effect on the transcript levels of genes associated with muscle fiber type differentiation and plasticity, the sarcomere complex, and pathways implicated in the regulation of muscle fiber size. Data from this first study characterizing the acute influence of neural activity on muscle mass and sarcomere gene expression in a teleost are discussed in the context of comparative studies in mammalian model systems and vertebrate species from different lineages.


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