Br J Sports Med. Published Online First: 9 January 2008. doi:10.1136/bjsm.2007.041970
Paper |
The role of lactate in the exercise-induced human growth hormone response: evidence from McArdle's disease
1 Liverpool, John Moores Universy, United Kingdom
2 Centre for Sports Medicine and Human Performance, Brunel University, United Kingdom
3 University of Chester, United Kingdom
4 Robert Jones and Agnes Hunt Orthopaedic NHS Trust, United Kingdom
* To whom correspondence should be addressed. E-mail: gregwhyte27{at}yahoo.co.uk.
Accepted 20 November 2007
Abstract
Purpose: Increased blood lactate concentration has been suggested as a primary stimulus for the exercise-induced growth hormone response (EIGR). Patients with McArdle’s disease are unable to produce lactate in response to exercise and thus offer a unique model to assess the role of lactate in the EIGR. Accordingly, McArdle’s patients were exercised to test the hypothesis that lactate is a major stimulus of the EIGR.
Methods. Eleven patients with McArdle’s disease (3 male, 8 female; age: 35.5 ± 13.9 years, height: 166 ± 8 cm, body mass: 75.2 ± 13.1 kg) were recruited for the study. The patients walked initially at 0.42 m/s, increasing by 0.14 m/s per 3 min stage. Exercise was terminated when participants completed 3-minutes at 1.80 m/s or when a Borg CR10 pain scale rating of "4" was reached. Stages were separated by 60 s for capillary blood sampling for analysis of hGH and blood lactate concentration.
Results. McArdle’s patients’ blood lactate levels remained at resting levels (0.3 – 1.2 mM) as exercise intensity increased. Nine out of eleven participants failed to demonstrate an EIGR obtaining hGH values below the clinical definition of a response (>3 µg/L).
Conclusion. The absence of an EIGR in nine out of eleven participants suggests that lactate could play a major role in the EIGR in humans.
Key Words: glycogen storage disease, hormone secretion, human growth hormone, physical activity
CiteULike 
Complore 
Connotea 
Del.icio.us 
Digg 
Reddit 
Technorati What's this?
- Full Text (Rapid PDF)
-
All Versions of this Article:
bjsm.2007.041970v1
bjsm.2007.041970v2
43/7/521 most recent - Submit a response
- Alert me when this article is cited
- Alert me when eLetters are posted
- Alert me if a correction is posted
Services
- Email this link to a friend
- Similar articles in this journal
- Similar articles in PubMed
- Add article to my folders
- Download to citation manager
Citing Articles
Google Scholar
PubMed
Bookmark with
Register for free content
The full back archive is now available for all BMJ Journals. Institutional subscribers may access the entire archive as part of their subscription. Personal subscribers will also have access to all content when logged in. Non-subscribers who register have free access to all articles published before 2006 right back to volume 1 issue 1. Register here to access the free archive of all BMJ Journals.
Don't forget to sign up for content alerts so you keep up to date with all the articles as they are published.
