Melatonin:
Effects of prophylactic N-Acetyl-5-
methoxytryptamine (melatonin)
supplementation and resistance
exercise on serum growth hormone
levels and the hypothalamus-pituitary-
adrenal axis in young males and females.
Baylor University also conducted a study
on the hormonal effects of melatonin,
which was supported by funding from
Iovate Health Sciences. Sixty physically
active subjects (30 men and 30 women)
were randomly assigned to one of three
groups.They ingested either .5mg of melatonin,
5.0 mg of melatonin, or a placebo.
Subjects underwent blood sampling every
15 min for 60 min after ingesting the supplement.
They then performed a single
bout of resistance exercise, and provided
additional blood samples every 15 min
for another 2 hours. Serum levels of GH,
IGF-1, IGFBP-1, IGFBP-3, and cortisol
were measured.The results were as follows.
5.0 mg melatonin caused a significantly
greater increase in GH (men) than placebo
prior to exercise,whereas both the .5 and
5.0 mg dose of melatonin seemed to cause
a greater increase in GH than placebo
post-exercise. No significant differences
occurred for IGF-1. The 5.0 mg melatonin
dose resulted in higher IGFBP-3 in
males, and .5 caused a higher post-exercise
cortisol response in females. 5mg seemed
to be the most appropriate dose for GH
elevation in males. No exact values were
given.