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Effect of resistance training on microvascular density and eNOS content in skeletal muscle of sedentary men

journal contribution
posted on 2014-11-01, 00:00 authored by M Cocks, Chris ShawChris Shaw, S O Shepherd, J P Fisher, A M Ranasinghe, T A Barker, K D Tipton, A J M Wagenmakers
OBJECTIVE: The effects of RT on muscle mass, strength, and insulin sensitivity are well established, but the underlying mechanisms are only partially understood. The main aim of this study was to investigate whether RT induces changes in endothelial enzymes of the muscle microvasculature, which would increase NO bioavailability and could contribute to improved insulin sensitivity. METHODS: Eight previously sedentary males (age 20 ± 0.4 years, BMI 24.5 ± 0.9 kg/m(2) ) completed six weeks of RT 3x/week. Muscle biopsies were taken from the m. vastus lateralis and microvascular density; and endothelial-specific eNOS content, eNOS Ser(1177) phosphorylation, and NOX2 content were assessed pre- and post-RT using quantitative immunofluorescence microscopy. Whole-body insulin sensitivity (measured as Matsuda Index), microvascular Kf (functional measure of the total available endothelial surface area), and arterial stiffness (AIx, central, and pPWV) were also measured. RESULTS: Measures of microvascular density, microvascular Kf , microvascular eNOS content, basal eNOS phosphorylation, and endothelial NOX2 content did not change from pre-RT to post-RT. RT increased insulin sensitivity (p < 0.05) and reduced resting blood pressure and AIx (p < 0.05), but did not change central or pPWV. CONCLUSIONS: RT did not change any measure of muscle microvascular structure or function.

History

Journal

Microcirculation

Volume

21

Issue

8

Pagination

738 - 746

Publisher

Wiley-Blackwell

Location

Chichester, Eng.

eISSN

1549-8719

Language

eng

Publication classification

C Journal article; C1.1 Refereed article in a scholarly journal

Copyright notice

2014, John Wiley & Sons