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Growth hormone and lactate responses induced by maximal isometric voluntary contractions and whole-body vibrations in healthy subjects.

Authors :
Sartorio A
Agosti F
De Col A
Marazzi N
Rastelli F
Chiavaroli S
Lafortuna CL
Cella SG
Rigamonti AE
Source :
Journal of endocrinological investigation [J Endocrinol Invest] 2011 Mar; Vol. 34 (3), pp. 216-21. Date of Electronic Publication: 2010 Sep 02.
Publication Year :
2011

Abstract

Background: In contrast with maximal voluntary resistance exercise, which is allegedly considered a potent GH stimulus in young subjects, evaluation of GH response to whole-body vibrations (WBV) has yielded conflicting results.<br />Methods: The acute effects of WBV alone (test A), maximal voluntary isometric contractions (MVC) (test B), and combination of WBV and MVC (test C) on serum GH and blood lactate (LA) levels were studied in 9 healthy adult males. Muscle soreness was assessed 24 and 48 h after exercise by a visual analogue scale.<br />Results: GH responses were significantly higher after tests B and C than after test A (GH peaks: 18.8 ± 9.5 ng/ml or 20.8 ± 13.7 ng/ml, respectively, vs 4.3 ± 3.5 ng/ml; p<0.05), with no difference between tests B and C. LA concentrations significantly increased after tests A, B, and C, being significantly higher after tests B and C than after test A (LA peaks: 2.0 ± 0.5 mmol/l or 6.7 ± 2.3 mmol/l, respectively, vs 7.6 ± 0.9 mmol/l; p<0.05). Peak LA values were significantly correlated to GH peaks in the 3 tests (r=0.48; p<0.05). Muscle soreness was significantly higher 24-48 h after tests B and C than after test A, no significant differences being present between tests B and C.<br />Conclusions: WBV stimulates GH secretion and LA production, with no additive effect when combined with repeated isometric voluntary contractions. Optimization of protocols based on WBV seems important to maximize the positive effects of this intervention on the somatotropic function.

Details

Language :
English
ISSN :
1720-8386
Volume :
34
Issue :
3
Database :
MEDLINE
Journal :
Journal of endocrinological investigation
Publication Type :
Academic Journal
Accession number :
20820130
Full Text :
https://doi.org/10.3275/7255