Correlations between plasma noradrenaline concentrations, antioxidants, and neutrophil counts after submaximal resistance exercise in men.
BACKGROUND
Generation of reactive oxygen species (ROS) during exercise has been linked to increased oxygen consumption. ROS could also be produced by other mechanisms-for example, a respiratory burst of neutrophils or catecholamine auto-oxidation-when oxygen consumption is only moderately increased.


OBJECTIVE
To investigate noradrenaline concentrations, neutrophil counts, plasma antioxidants, and lipid oxidation products before and after acute resistance exercise.


METHODS
17 male participants undertook a submaximal resistance exercise circuit (10 exercises; 75% of the one repetition maximum; mean (SD) exercise time, 18.6 (1.1) minutes). Blood samples were taken before and immediately after exercise and analysed for plasma antioxidants, noradrenaline, neutrophils, and lipid oxidation products. Wilcoxon's signed-rank test and Pearson's correlation coefficient were used for calculations.


RESULTS
Neutrophils, noradrenaline, fat soluble antioxidants, and lipid oxidation products increased after exercise. Noradrenaline concentrations were associated with higher antioxidant concentrations. Neutrophils were related to higher concentrations of conjugated dienes.


CONCLUSIONS
Submaximal resistance exercise increases plasma antioxidants. This might reflect enhanced antioxidant defence in response to the oxidative stress of exercise, though this is not efficient for inhibiting lipid oxidation. The correlation between noradrenaline concentrations and plasma antioxidants suggests a modulating role of the stress hormone. Neutrophils are a possible source of oxidative stress after resistance exercise.
Ramel
A
A
Unit for Nutrition Research, University of Iceland, Reykjavik, Iceland. ramel@hi.is <ramel@hi.is>
Wagner
K-H
KH
Elmadfa
I
I
D000328:Adult; D000975:Antioxidants / Q000378:metabolism*; D001205:Ascorbic Acid / Q000378:metabolism; D001642:Bicycling / Q000502:physiology; D015444:Exercise / Q000502:physiology*; D006801:Humans; D007958:Leukocyte Count; D044243:Linoleic Acids, Conjugated / Q000378:metabolism; D008297:Male; D008315:Malondialdehyde / Q000378:metabolism; D009504:Neutrophils / Q000378:metabolism*; D009638:Norepinephrine / Q000378:metabolism*; D010101:Oxygen Consumption / Q000502:physiology; D010807:Physical Endurance / Q000502:physiology; D010953:Plasma Volume / Q000502:physiology; D017382:Reactive Oxygen Species / Q000378:metabolism; D012420:Running / Q000502:physiology
D000975:Antioxidants; D044243:Linoleic Acids, Conjugated; D017382:Reactive Oxygen Species; D008315:Malondialdehyde; D001205:Ascorbic Acid; D009638:Norepinephrine