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Published on: November 14, 2013
Exercise increases the level of plasma orexin A in humans
Background:
The purpose of this research was to study the effects of exercise on the concentration of plasma orexin A, a peptide regulating several physiological functions.
Methods:
Blood samples were collected from participants (men, n=10; age: 24.4±2.93 years) 15, 0 min before the start of exercise, and 30, 45, 60 min after a cycle ergometer exercise at 75 W for 15 min. Also heart rate (HR), galvanic skin response (GSR), and rectal temperature were monitored.
Results:
The exercise induced a significant increase (p<0.01) in plasmatic orexin A with a peak at 30 min after the exercise bout, in association with an increase of the other three monitored variables: HR (p<0.01), GSR (p<0.05), and rectal temperature (p<0.01).
Conclusions:
Our findings indicate that plasmatic orexin A is involved in the reaction to physical activity.
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