Serum Growth Hormone Response to Exercise in Non-Obese and Obese Normal Subjects

Abstract

The serum growth hormone response to a very mild, but prolonged exercise load – 225 kgm/min for 60 minutes – has been studied in 6 young non-obese healthy male subjects and 6 young obese healthy male subjects. The exercise load was easily tolerated by all subjects, and pulse rates at rest and during exercise were not much different in the two groups. The exercise-induced growth hormone rise in the non-obese subjects was discernible 30 minutes after start of work, and the maximum value of 26 ng/ml was reached 10 minutes after cessation of work. In contrast, no rise at all was seen in any of the obese subjects. It is thus demonstrated that exercise is similar to other growth-hormone-releasing stimuli: their potency is reduced in obesity.

Key Words:

• Exercise
• free fatty acids
• glucose
• growth hormone
• insulin
• obesity