The effects of oral arginine supplementation on growth hormone, arginine, and somatomedin levels during energy restriction in male weight lifters
<p>Twelve male weight lifters were used to study the effect of oral arginine consumption on growth hormone (hGH) , arginine (Arg), and somatomedin (IGF-1) concentrations. Subjects were randomly assigned to treatment or placebo groups. Following a week of controlled exercise and diet, fasted su...
| Main Author: | |
|---|---|
| Other Authors: | |
| Format: | Others |
| Language: | en |
| Published: |
Virginia Tech
2014
|
| Subjects: | |
| Online Access: | http://hdl.handle.net/10919/45993 http://scholar.lib.vt.edu/theses/available/etd-11242009-020056/ |
| Summary: | <p>Twelve male weight lifters were used to study the
effect of oral arginine consumption on growth hormone (hGH) ,
arginine (Arg), and somatomedin (IGF-1) concentrations.
Subjects were randomly assigned to treatment or placebo
groups. Following a week of controlled exercise and diet,
fasted subjects took either an acute dose of arginine
hydrochloride or casein (placebo), at 0.1 g/kg BW. Blood
samples were drawn every 15 min, for 90 min after ingestion.
All samples were analyzed for hGH and Arg, and IGF-1 was
measured in the baseline sample. Subjects then underwent 10
days of caloric restriction, consuming a liquid diet of 22
kcal/kg BW/d. Subjects took either arginine or casein
supplements in two doses of 0.1 g/kg BW twice daily, for a
total dose of 0.2 g/kg BW/d. The weight lifting protocol
remained unchanged. On day 17, subjects were again tested
for the acute response to a single dose of 0.1 g/kg BW
supplement (arginine or placebo) over 90 min. Blood was
collected and analyzed as before. No change in hGH and Arg
occurred 90 min after consumption of the arginine
supplement, regardless of dietary condition. However,
arginine supplementation caused overall higher hGH and Arg levels (2.64 ng/ml and 0.87 mmol/l) compared to placebo
(1.36 ng/ml and 0.71 mmol/l) during caloric restriction.
IGF-1 did not change in either group under either diet.
Thus, oral arginine supplementation at 0.1 g/kg BW did not
produce a rise in hGH or Arg after 90 min, and did not
affect overall hGH status, as measured by IGF-1, during
energy restriction and supplementation.</p> === Master of Science |
|---|