Teaching skeletal muscle adaptations to aerobic exercise using an American Physiological Society classic paper by Dr. Philip Gollnick and colleagues

The use of primary research in the classroom enhances the critical thinking abilities of students. The present article describes a strategy for using the American Physiological Society classic paper “Enzyme activity and fiber composition in skeletal muscle of untrained and trained men” by Dr. Philip D. Gollnick and colleagues to enhance the students’ ability to understand research, increase their knowledge of the adaptations to exercise, and learn computer skills in data analysis and presentation. By having students read, study, prepare graphs, and discuss the data from a classic paper, they gain an improved understanding of the factors that influence aerobic exercise ability. This study is especially useful for illuminating the exercise-specific differences in bioenergetic enzymes, muscle fiber type, and fitness characteristics that exist between untrained and trained individuals.

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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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Regulation of exercise-induced fiber type transformation, mitochondrial biogenesis, and angiogenesis in skeletal muscle

Journal of Applied Physiology ◽

10.1152/japplphysiol.00993.2010 ◽

2011 ◽

Vol 110 (1) ◽

pp. 264-274 ◽

Cited By ~ 163

Author(s):

Zhen Yan ◽

Mitsuharu Okutsu ◽

Yasir N. Akhtar ◽

Vitor A. Lira

Keyword(s):

Skeletal Muscle ◽

Mitochondrial Biogenesis ◽

Contractile Activity ◽

Fiber Type ◽

Genetically Engineered ◽

Type Transformation ◽

Muscle Adaptations ◽

Exercise Induced ◽

Skeletal Muscle Adaptations ◽

Muscle Contractile

Skeletal muscle exhibits superb plasticity in response to changes in functional demands. Chronic increases of skeletal muscle contractile activity, such as endurance exercise, lead to a variety of physiological and biochemical adaptations in skeletal muscle, including mitochondrial biogenesis, angiogenesis, and fiber type transformation. These adaptive changes are the basis for the improvement of physical performance and other health benefits. This review focuses on recent findings in genetically engineered animal models designed to elucidate the mechanisms and functions of various signal transduction pathways and gene expression programs in exercise-induced skeletal muscle adaptations.

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Skeletal Muscle Adaptations to Cancer and its Treatment: Their Fundamental Basis and Contribution to Functional Disability

Critical Reviews in Eukaryotic Gene Expression ◽

10.1615/critreveukaryotgeneexpr.2013007650 ◽

2013 ◽

Vol 23 (4) ◽

pp. 283-297 ◽

Cited By ~ 3

Author(s):

Hirak Der-Torossian ◽

Marion E. Couch ◽

Kim Dittus ◽

Michael J. Toth

Keyword(s):

Skeletal Muscle ◽

Functional Disability ◽

Muscle Adaptations ◽

Skeletal Muscle Adaptations

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Genetic and other determinants of AMP deaminase activity in healthy adult skeletal muscle

Journal of Applied Physiology ◽

10.1152/jappl.1998.85.4.1273 ◽

1998 ◽

Vol 85 (4) ◽

pp. 1273-1278 ◽

Cited By ~ 33

Author(s):

Barbara Norman ◽

Donna K. Mahnke-Zizelman ◽

Amy Vallis ◽

Richard L. Sabina

Keyword(s):

Skeletal Muscle ◽

Enzyme Activity ◽

Mutant Allele ◽

Fiber Type ◽

Type I ◽

Training Status ◽

Amp Deaminase ◽

Normal Allele ◽

Relative Percentage ◽

Type I Fibers

AMPD1 genotype, relative fiber type composition, training status, and gender were evaluated as contributing factors to the reported variation in AMP deaminase enzyme activity in healthy skeletal muscle. Multifactorial correlative analyses demonstrate that AMPD1 genotype has the greatest effect on enzyme activity. An AMPD1 mutant allele frequency of 13.7 and a 1.7% incidence of enzyme deficiency was found across 175 healthy subjects. Homozygotes for the AMPD1 normal allele have high enzyme activities, and heterozygotes display intermediate activities. When examined according to genotype, other factors were found to affect variability as follows: AMP deaminase activity in homozygotes for the normal allele exhibits a negative correlation with the relative percentage of type I fibers and training status. Conversely, residual AMP deaminase activity in homozygotes for the mutant allele displays a positive correlation with the relative percentage of type I fibers. Opposing correlations in different homozygous AMPD1 genotypes are likely due to relative fiber-type differences in the expression of AMPD1 and AMPD3 isoforms. Gender also contributes to variation in total skeletal muscle AMP deaminase activity, with normal homozygous and heterozygous women showing only 85–88% of the levels observed in genotype-matched men.

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