Document Detail


Growth hormone responses to acute resistance exercise with vascular restriction in young and old men.
MedLine Citation:
PMID:  22727808     Owner:  NLM     Status:  MEDLINE    
Abstract/OtherAbstract:
OBJECTIVE: Resistance exercise (RE) stimulates growth hormone (GH) secretion in a load-dependent manner, with heavier loads producing larger GH responses. However, new research demonstrates that low-load RE performed with blood flow restriction (BFR) produces potent GH responses that are similar to or exceed those produced following high-load RE. We hypothesized that low-load RE with vascular restriction would attenuate the known age-related reduction in GH response to RE.
DESIGN: In a randomized crossover design, ten young (28 ± 7.8 years) and ten older (67.4 ± 4.6 years) men performed bilateral knee extension RE with low-load [20% of one-repetition maximum (1RM)] with BFR and high-load (80% 1RM) without BFR. GH and lactate were measured every 10 minutes throughout a 150-minute testing session (30 minutes prior to and 120 minutes following completion of the exercise); IGF-I was measured at baseline and 60 minutes post-exercise.
RESULTS: Area under the GH curve indicated that both age groups responded similarly to each exercise condition. However, young men had a significantly greater maximal GH response to low-load RE with BFR than the high-load condition without BFR. Additionally, younger men had greater maximal GH concentrations to low-load RE with BFR than older men (p=0.02). The GH responses were marginally correlated to lactate concentration (r=0.13, p=0.002) and IGF-I levels were unchanged with RE.
CONCLUSIONS: GH responses to low-load RE with vascular restriction are slightly higher than high-load RE without vascular restriction in young men. However, low-load RE with vascular restriction did not attenuate the known age-related reduction in GH response with exercise. These data suggest that while low-load RE with vascular restriction is as effective for inducing a GH response than traditionally-based high-load RE, there is a more potent response in young men.
Authors:
Todd M Manini; Joshua F Yarrow; Thomas W Buford; Brian C Clark; Christine F Conover; Stephen E Borst
Related Documents :
19207478 - Cardiac functional reserve is diminished in growth hormone-deficient adults.
20678128 - "exercise-induced cardiac fatigue"--a review of the echocardiographic literature.
1642718 - Behavior of cardiac output during progressive exercise tests: a preliminary report.
9187608 - Noninvasive determination of cardiac output in a model of acute lung injury.
21220738 - Heart rate response during exercise and pregnancy outcome in women with congenital hear...
3344838 - Organization of energy provision in rainbow trout during exercise.
Publication Detail:
Type:  Journal Article; Research Support, N.I.H., Extramural; Research Support, U.S. Gov't, Non-P.H.S.     Date:  2012-06-23
Journal Detail:
Title:  Growth hormone & IGF research : official journal of the Growth Hormone Research Society and the International IGF Research Society     Volume:  22     ISSN:  1532-2238     ISO Abbreviation:  Growth Horm. IGF Res.     Publication Date:  2012 Oct 
Date Detail:
Created Date:  2012-08-27     Completed Date:  2013-06-24     Revised Date:  2014-07-10    
Medline Journal Info:
Nlm Unique ID:  9814320     Medline TA:  Growth Horm IGF Res     Country:  Scotland    
Other Details:
Languages:  eng     Pagination:  167-72     Citation Subset:  IM    
Copyright Information:
Copyright © 2012. Published by Elsevier Ltd.
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Descriptor/Qualifier:
Aged
Databases, Factual
Exercise / physiology*
Human Growth Hormone / blood*
Humans
Male
Muscle, Skeletal / blood supply,  physiology
Regional Blood Flow
Resistance Training*
Grant Support
ID/Acronym/Agency:
P30 AG028740/AG/NIA NIH HHS; P30AG028740/AG/NIA NIH HHS
Chemical
Reg. No./Substance:
12629-01-5/Human Growth Hormone
Comments/Corrections

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine


Previous Document:  A novel ultrasensitive LC-MS/MS assay for quantification of intracellular raltegravir in human cell ...
Next Document:  Protection of exenatide for retinal ganglion cells with different glucose concentrations.