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Conducting Maximal and Submaximal Endurance Exercise Testing to Measure Physiological and Biological Responses to Acute Exercise in Humans
Published on: October 17, 2018
Norepinephrine response to exercise at the same relative intensity before and after endurance exercise training
J S Greiwe1, R C Hickner, S D Shah
1Department of Internal Medicine, Washington University School of Medicine, St. Louis, Missouri 63110, USA.
Journal of Applied Physiology (Bethesda, Md. : 1985)
|February 4, 1999
Summary
Endurance exercise training increases norepinephrine (NE) response to relative exercise intensities. This study shows that NE response depends on both absolute and relative exercise intensity after training.
Area of Science:
- Exercise Physiology
- Human Physiology
- Sports Science
Background:
- Endurance training typically blunts the norepinephrine response to absolute exercise intensities.
- Previous research on the effect of training on catecholamine response to relative exercise intensities yielded conflicting results.
Purpose of the Study:
- To investigate the effect of endurance exercise training on the catecholamine response during exercise at the same relative intensity.
- To clarify the relationship between exercise intensity (absolute vs. relative) and catecholamine response post-training.
Main Methods:
- Six men and three women (28 ± 8 years) completed 10 weeks of endurance training.
- Maximal oxygen uptake (VO2 max) was measured before and after training.
- Participants completed 15-minute treadmill exercise bouts at 60-85% of VO2 max before and after training.
Main Results:
- VO2 max increased by 20% after training (P < 0.05).
- Plasma norepinephrine concentrations were significantly higher during exercise at 65-85% of VO2 max post-training compared to pre-training (P < 0.05).
- No significant differences in heart rate or plasma epinephrine were observed between pre- and post-training.
Conclusions:
- Endurance exercise training enhances the norepinephrine response to exercise at the same relative intensity.
- The norepinephrine response to exercise is influenced by both absolute and relative exercise intensity.
- These findings contribute to understanding the physiological adaptations to endurance training.
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