Skeletal muscle adaptations to endurance training in 60- to 70-yr-old men and women

Previous studies of endurance exercise training in older men and women generally have found only minimal skeletal muscle adaptations to training. To evaluate the possibility that this may have been due to an inadequate training stimulus, we studied 23 healthy older (64 +/- 3 yr) men and women before and after they had trained by walking/jogging at 80% of maximal heart rate for 45 min/day 4 days/wk for 9–12 mo. This training program resulted in a 23% increase in maximal O2 consumption. Needle biopsy samples of the lateral gastrocnemius muscle were obtained before and after training and analyzed for selected histochemical and enzymatic characteristics. The percentage of type I muscle fibers did not change with training. The percentage of type IIb fibers, however, decreased from 19.1 +/- 9.1 to 15.1 +/- 8.1% (P less than 0.001), whereas the percentage of type IIa fibers increased from 22.1 +/- 7.7 to 29.6 +/- 9.1% (P less than 0.05). Training also induced increases in the cross-sectional area of both type I (12%; P less than 0.001) and type IIa fibers (10%; P less than 0.05). Capillary density increased from 257 +/- 43 capillaries/mm2 before training to 310 +/- 48 capillaries/mm2 after training (P less than 0.001) because of increases in the capillary-to-fiber ratio and in the number of capillaries in contact with each fiber. Lactate dehydrogenase activity decreased by 21% (P less than 0.001), whereas the activities of the mitochondrial enzymes succinate dehydrogenase, citrate synthase, and beta-hydroxyacyl-CoA dehydrogenase increased by 24–55% in response to training (P less than 0.001–0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

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Skeletal muscle adaptations in elastic resistance-trained young men and women

European Journal of Applied Physiology ◽

10.1007/s004210100495 ◽

2001 ◽

Vol 86 (2) ◽

pp. 112-118 ◽

Cited By ~ 32

Author(s):

David Hostler ◽

Chris Schwirian ◽

Gerson Campos ◽

Kumika Toma ◽

Matthew Crill ◽

...

Keyword(s):

Skeletal Muscle ◽

Young Men ◽

Men And Women ◽

Elastic Resistance ◽

Muscle Adaptations ◽

Skeletal Muscle Adaptations

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Strength-Training Induces Skeletal Muscle Adaptations in Patients with Myotonic Dystrophy Type I

Medicine & Science in Sports & Exercise ◽

10.1249/01.mss.0000486923.39242.9a ◽

2016 ◽

Vol 48 ◽

pp. 641 ◽

Cited By ~ 1

Author(s):

Marie-Pier Roussel ◽

Marika Morin ◽

Émile Petitclerc ◽

Anne-Marie Fortin ◽

Cynthia Gagnon ◽

...

Keyword(s):

Skeletal Muscle ◽

Strength Training ◽

Myotonic Dystrophy ◽

Type I ◽

Myotonic Dystrophy Type ◽

Muscle Adaptations ◽

Skeletal Muscle Adaptations

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Skeletal muscle and cardiac changes with training in patients with angina pectoris

AJP Heart and Circulatory Physiology ◽

10.1152/ajpheart.1982.243.5.h830 ◽

1982 ◽

Vol 243 (5) ◽

pp. H830-H836 ◽

Cited By ~ 3

Author(s):

R. J. Ferguson ◽

A. W. Taylor ◽

P. Cote ◽

J. Charlebois ◽

Y. Dinelle ◽

...

Keyword(s):

Skeletal Muscle ◽

Heart Rate ◽

Oxygen Consumption ◽

Angina Pectoris ◽

Exercise Capacity ◽

Left Ventricular ◽

Exercise Heart Rate ◽

Type I ◽

Muscle Adaptations ◽

Skeletal Muscle Adaptations

Cardiovascular and skeletal muscle adaptations were studied before and after 6 mo of physical training in patients with coronary artery disease and exertional angina pectoris. Symptom-limited exercise capacity increased by 41% (470 +/- 30 to 665 +/- 35 kg.m.min-1; n = 29, P less than 0.001) with training as did skeletal muscle succinate dehydrogenase activity (1.75 +/- 0.24 to 3.31 +/- 0.24 IU; n = 23, P less than 0.001) and the areas of muscle fibers (type I from 43.6 +/- 3.3 to 54.4 +/- 3.3 micrometers 2 X 10(2); n = 21, P less than 0.05 and type II from 43.9 +/- 2.4 to 57.2 +/- 5.1 micrometers 2 X 10(2); P less than 0.01). At the same submaximal exercise intensity (mean 355 +/- 100 km.m.min-1), plasma catecholamines (1.31 +/- 0.14 to 1.07 +/- 0.09 ng.ml-1; n = 13, P less than 0.05), heart rate (115 +/- 3 to 97 +/- 3 beats/min; n = 29, P less than 0.001), and systolic blood pressure (171 +/- 4 to 143 +2- 4 mmHg; n = 29, P less than 0.001) were significantly reduced after training. Maximal coronary sinus blood flow (192 +/- 10 to 208 +/- 9 ml.min-1; n = 29, P less than 0.05) and left ventricular oxygen consumption (23.2 +/- 1.5 to 25.8 +/- 1.6 ml.min-1; n = 24, P less than 0.05) were increased by 8 and 11%, respectively, after training. The improvement in exercise capacity with training in patients with exercise is secondary to a reduction in myocardial oxygen requirements during subangina levels of exercise and partly to a small increase in maximal myocardial oxygen consumption. The skeletal muscle adaptations with training were not related to other indices of training such as the reduced exercise heart rate or increased symptom-limited exercise capacity.

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SKELETAL MUSCLE ADAPTATIONS IN ELASTIC RESISTANCE-TRAINED YOUNG MEN AND WOMEN

Medicine & Science in Sports & Exercise ◽

10.1097/00005768-199905001-01628 ◽

1999 ◽

Vol 31 (Supplement) ◽

pp. S325

Author(s):

D. Hostler ◽

C. I. Schwirian ◽

F. C. Hagerman ◽

R. S. Staron ◽

G. Campos ◽

...

Keyword(s):

Skeletal Muscle ◽

Young Men ◽

Men And Women ◽

Elastic Resistance ◽

Muscle Adaptations ◽

Skeletal Muscle Adaptations

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PO-048 Effects of royal jelly administration on endurance training-induced mitochondrial adaptations in skeletal muscle

Exercise Biochemistry Review ◽

10.14428/ebr.v1i3.10133 ◽

2018 ◽

Vol 1 (3) ◽

Author(s):

Yumiko Takahashi ◽

Kamiyu Hijikata ◽

Hideo Hatta

Keyword(s):

Skeletal Muscle ◽

Endurance Training ◽

Soleus Muscle ◽

Royal Jelly ◽

Citrate Synthase ◽

Treadmill Running ◽

Type I ◽

Mitochondrial Enzymes ◽

Positive Effects ◽

Hydroxyacyl Coa Dehydrogenase

Objective In this study, we investigated effect of royal jelly (RJ), which is produced by honey bees to feed to developing larvae and contains various ingredients including protein, carbohydrate, lipids and minerals, on endurance training-induced adaptations in skeletal muscle in ICR mice. Methods Male mice received either RJ (1.0 mg/g body weight) or distilled water for 3 weeks. Mice in the training group performed treadmill running at 20 m/min for 60 min from 30 min after the administration five times a week. Results We found a significant positive main effects of RJ treatment on the weight of tibialis anterior (TA) muscle and gastrocnemius muscle. There was a significant positive main effect of endurance training on the maximum activities of citrate synthase and β-hydroxyacyl CoA dehydrogenase, which are mitochondrial enzymes, in TA and plantaris muscle (type IIb/IIx dominant), while no significant effect of RJ treatment was found. In soleus muscle (about 40% fiber consistent with type I), the maximum activities of citrate synthase and β-hydroxyacyl CoA dehydrogenase were significantly increased by endurance training in the RJ treated group, while no significant effect of endurance training was found in the control group. Conclusions Our results suggest that RJ treatment had positive effects on the induction of mitochondrial adaptation by endurance training in soleus muscle.

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Skeletal muscle of females and males with constitutional thinness: a low intramuscular lipid content and oxidative profile

Applied Physiology Nutrition and Metabolism ◽

10.1139/apnm-2020-0068 ◽

2020 ◽

Vol 45 (11) ◽

pp. 1287-1298 ◽

Cited By ~ 1

Author(s):

Mélina Bailly ◽

Natacha Germain ◽

Léonard Féasson ◽

Frédéric Costes ◽

Bruno Estour ◽

...

Keyword(s):

Skeletal Muscle ◽

Weight Control ◽

Glycogen Content ◽

Citrate Synthase ◽

Fiber Type ◽

Muscle Fibers ◽

Oxidative Capacity ◽

Normal Weight ◽

Type I ◽

Before And After

Constitutional thinness (CT) is a nonpathological state of underweight. The current study aimed to explore skeletal muscle energy storage in individuals with CT and to further characterize muscle phenotype at baseline and in response to overfeeding. Thirty subjects with CT (15 females, 15 males) and 31 normal-weight control subjects (16 females, 15 males) participated in the study. Histological and enzymological analyses were performed on muscle biopsy specimens before and after overfeeding. In the skeletal muscle of CT participants compared with controls, we observed a lower content of intramuscular triglycerides for type I (−17%, p < 0.01) and type IIA (−14%, p < 0.05) muscle fibers, a lower glycogen content for type I (−6%, p < 0.01) and type IIA (−5%, p < 0.05) muscle fibers, a specific fiber-type distribution, a marked muscle hypotrophy (−20%, p < 0.001), a low capillary-to-fiber ratio (−19%, p < 0.001), and low citrate synthase activity (−18%, p < 0.05). In response to overfeeding, CT participants increased their intramuscular triglycerides content in type I (+10%, p < 0.01) and type IIA (+9%, p < 0.01) muscle fibers. CT individuals seem to present an unusual muscle phenotype and different adaptations to overfeeding compared with normal-weight individuals, suggesting a specific energy metabolism and muscle adaptations. ClinicalTrials.gov registration no. NCT02004821. Novelty Low intramuscular triglycerides and glycogen content in skeletal muscle of constitutionally thin individuals. Low oxidative capacity, low capillary supply, and fiber hypotrophy in skeletal muscle of constitutionally thin individuals. Increase in intramuscular triglycerides in constitutional thinness in response to overfeeding.

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Skeletal muscle adaptations during early phase of heavy-resistance training in men and women

Journal of Applied Physiology ◽

10.1152/jappl.1994.76.3.1247 ◽

1994 ◽

Vol 76 (3) ◽

pp. 1247-1255 ◽

Cited By ~ 371

Author(s):

R. S. Staron ◽

D. L. Karapondo ◽

W. J. Kraemer ◽

A. C. Fry ◽

S. E. Gordon ◽

...

Keyword(s):

Skeletal Muscle ◽

Resistance Training ◽

Fiber Type ◽

Dynamic Strength ◽

Men And Women ◽

Leg Extension ◽

Type Composition ◽

Muscle Adaptations ◽

Skeletal Muscle Adaptations ◽

Maximal Dynamic Strength

An 8-wk progressive resistance training program for the lower extremity was performed twice a week to investigate the time course for skeletal muscle adaptations in men and women. Maximal dynamic strength was tested biweekly. Muscle biopsies were extracted at the beginning and every 2 wk of the study from resistance-trained and from nontrained (control) subjects. The muscle samples were analyzed for fiber type composition, cross-sectional area, and myosin heavy chain content. In addition, fasting blood samples were measured for resting serum levels of testosterone, cortisol, and growth hormone. With the exception of the leg press for women (after 2 wk of training) and leg extension for men (after 6 wk of training), absolute and relative maximal dynamic strength was significantly increased after 4 wk of training for all three exercises (squat, leg press, and leg extension) in both sexes. Resistance training also caused a significant decrease in the percentage of type IIb fibers after 2 wk in women and 4 wk in men, an increase in the resting levels of serum testosterone after 4 wk in men, and a decrease in cortisol after 6 wk in men. No significant changes occurred over time for any of the other measured parameters for either sex. These data suggest that skeletal muscle adaptations that may contribute to strength gains of the lower extremity are similar for men and women during the early phase of resistance training and, with the exception of changes in the fast fiber type composition, that they occur gradually.

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