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Old 05-24-2006, 07:47 PM   #1
Charlie Reid
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I'm planning on doing some undergraduate research on Growth Hormone Responses to Diet and Exercise. I'm starting to gather literature now so i can work on it this fall before i graduate. Does anybody have any literature on Growth Hormone research? Robb Wolf? I'm particularly interested in the IF Fasting stuff, muscle gain on a hypocaloric diet and the body composition benefits of GH due to it being lypolytic in nature. Any help/suggestions/ideas would be greatly appreciated!
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Old 05-25-2006, 11:36 AM   #2
John Seaburg
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As far as I know, measuring HGH directly is difficult. The way we do it is to measure Insulin Growth Factor One (IGF-1). We have 3 1/2 years of data showing how exercise and diet affect IGF-1 and many other health markers. We don't count calories or look at total body fat so it might not help you.
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Old 05-26-2006, 12:59 PM   #3
Robert Wolf
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Here is a fun one:


Fasting Enhances Growth Hormone Secretion and Amplifies the Complex
Rhythms of Growth Hormone Secretion in Man
Klan Y. Ho,* Johannes D. Veldhuls,* Michael L. Johnson,* Richard Furlanetto,9 William S. Evans,*
K. G. M. M. Alberti,11 and Michael 0. Thomer*
Departments of*Internal Medicine and tPharmacology, University of Virginia Medical School, Charlottesville, Virginia 22908;
§The Childrens Hospital ofPhiladelphia, University ofPennsylvania, Philadelphia, Pennsylvania 19104;
and "lthe Royal Victoria Infirmary, Newcastle Upon Tyne, England
Abstract
Studies in man have shown that the episodic release of growth
hormone (GH) is infrequent and erratic, and unlike that in the
rat does not appear to have discernible ultradian periodicities.
However, these observations in nonfasted subjects may be invalid
since mixed nutrients have unpredictable effects on GH
release. Moreover, in the fed state basal GH levels are frequently
undetectable, thus rendering the identification of low
amplitude pulses unreliable. Accordingly, the 24-h pulsatile
pattern of GH secretion obtained from repetitive venous sampling
in six normal adult male subjects was examined during a
control fed day and during the first and fifth days of a 5-d fast.
The GH data were analyzed using two distinct methods: a
discrete pulse detection algorithm (Cluster analysis) and Fourier
expansion time-series, which allows fixed periodicities of
secretory activity to be resolved. The 5-d fast resulted in a
significant increase in discrete GH pulse frequency (5.8±0.7
vs. 9.9±0.7 pulses/24 h, P = 0.028), 24 h integrated GH concentration
(2.82±0.50 vs. 8.75±0.82 g min/ml; P = 0.0002),
and maximal pulse amplitude (5.9±1.1 vs. 12.3±1.6 ng/ml, P
< 0.005). While multiple low-amplitude sinusoidal periodicities
were present on the control fed day, time-series analysis
revealed enhancement of circadian and ultradian cycles on the
first and fifth days of fasting. Concomitantly, fasting resulted
in a decline (day 1 vs. day 5) in serum concentrations of somatomedin
C (1.31±0.22 vs. 0.77±0.18 U/ml) and glucose
(4.9±0.2 vs. 3.2±0.2 mmol/liter), and a marked rise in free
fatty acid (0.43±0.12 vs. 1.55±0.35 mmol/liter) and acetoacetate
(35±6 vs. 507±80 nmol/liter).
We conclude that the acute nutritional status is an important
determinant of spontaneous pulsatile GH secretion in
man. Fast-induced enhancement of GH release is achieved
through combined frequency (discrete pulses) and amplitude
(sinusoidal periodicities) modulation. Such alterations in somatotropic
hormone release may play an important role in
substrate homeostasis during starvation.
Introduction
Growth hormone (GH)' is secreted episodically in man. Although
it is well established that GH release is entrained to the
This work was presented in part at the 68th Annual Meeting of the
Endocrine Society, Anaheim, CA, 25-27 June 1986.
Receivedfor publication 2 February 1987 and in revisedform 16
November 1987.
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Old 05-26-2006, 01:02 PM   #4
Robert Wolf
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Also...that is a super slippery topic to study as GH is secreted in pulsitle fashion with diurnal (day/night) variations. You would need to establish a 24hr baseline over many days and then introduce various interventions...possibly in a crossover fashion.

This is why I stuck to analytical chemistry! Studying the whole critter is really hard.
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Old 05-27-2006, 08:23 AM   #5
Matthew Hoyle
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Charlie, try this website I found today.

http://assets.cambridge.org/052164/1...41888wsc00.pdf
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Old 05-29-2006, 07:51 PM   #6
Charlie Reid
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thanks guys. Hormones are real beast to study and very hard to measure, therefore i'm probably going to just end up doing a review of literature. The hormonal stuff seems to be the most interesting to me, therefore i'm going to stick to my guns.
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