Relationships Between Muscle Strength and Indices of Muscle Cross-Sectional Area Determined During Maximal Voluntary Contraction in Middle-Aged and Elderly Individuals

The present study examined associations between the ciliary neurotrophic factor (CNTF) 1357 G → A polymorphism and the muscle strength response to a unilateral, upper arm resistance-training (RT) program among healthy, young adults. Subjects were 754 Caucasian men (40%) and women (60%) who were genotyped and performed a training program of the nondominant (trained) arm with the dominant (untrained) arm as a comparison. Peak elbow flexor strength was measured with one repetition maximum, isometric strength with maximum voluntary contraction, and bicep cross-sectional area with MRI in the trained and untrained arms before and after training. Women with the CNTF GG genotype gained more absolute isometric strength, as measured by MVC (6.5 ± 0.3 vs. 5.2 ± 0.5 kg), than carriers of the CNTF A1357 allele in the trained arm pre- to posttraining ( P < 0.05). No significant associations were seen in men. Women with the CNTF GG genotype gained more absolute dynamic (1.0 ± 0.1 vs. 0.6 ± 0.1 kg) and allometric (0.022 ± 0.0 vs. 0.015 ± 0.0 kg/kg−0.67) strength, as measured by 1 RM, than carriers of the CNTF A1357 allele in the untrained arm pre- to posttraining ( P < 0.05). No significant associations were seen in men. No significant associations, as measured by cross-sectional area, were seen in men or women. The CNTF 1357 G → A polymorphism explains only a small portion of the variability in the muscle strength response to training in women.

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Bilateral and Unilateral Neuromuscular Function and Muscle Cross-Sectional Area in Middle-Aged and Elderly Men and Women

The Journals of Gerontology Series A ◽

10.1093/gerona/51a.1.b21 ◽

1996 ◽

Vol 51A (1) ◽

pp. B21-B29 ◽

Cited By ~ 71

Author(s):

K. Hakkinen ◽

W. J. Kraemer ◽

M. Kallinen ◽

V. Linnamo ◽

U.-M. Pastinen ◽

...

Keyword(s):

Neuromuscular Function ◽

Cross Sectional Area ◽

Sectional Area ◽

Middle Aged ◽

Elderly Men ◽

Cross Sectional ◽

Men And Women ◽

Muscle Cross Sectional Area

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Gender- and height-related limits of muscle strength in world weightlifting champions

Journal of Applied Physiology ◽

10.1152/jappl.2000.89.3.1061 ◽

2000 ◽

Vol 89 (3) ◽

pp. 1061-1064 ◽

Cited By ~ 27

Author(s):

Lincoln E. Ford ◽

Alvin J. Detterline ◽

Kevin K. Ho ◽

Wenyuan Cao

Keyword(s):

Muscle Strength ◽

Body Mass ◽

Common Factor ◽

Body Height ◽

Cross Sectional Area ◽

Sectional Area ◽

Cross Sectional ◽

Muscle Cross Sectional Area ◽

The Relationship ◽

Contractile Tissue

To assess factors that limit human muscle strength and growth, we examined the relationship between performance and body dimensions in the world weightlifting champions of 1993–1997. Weight lifted varied almost exactly with height squared (Ht2.16), suggesting that muscle mass scaled almost exactly with height cubed (Ht3.16) and that muscle cross-sectional area was closely correlated with body height, possibly because height and the numbers of muscle fibers in cross section are determined by a common factor during maturation. Further height limitations of muscle strength were shown by only one male champion ≥183 cm and no female champions ≥175 cm. The ratio of weight lifted to mean body cross-sectional area was approximately constant for body-weight classes ≤83 kg for men and ≤64 kg for women and decreased abruptly for higher weight classes. These findings suggest a nearly constant fraction of body mass devoted to muscle in lighter lifters and a lesser fraction in heavier lifters. Analysis also suggests that contractile tissue comprises ∼30% less body mass in female champions.

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