Exhaustive exercise modifies oxidative stress in smoking subjects.
BACKGROUND
Exhaustive exercise is associated with increased metabolic rate and accelerated generation of reactive oxygen species. Cigarette smoke also contains oxidants that may participate in the development of atherosclerosis. However, data on the association between exercise and smoking are sparse.


METHODS
A homogenous group of 30 young men (15 smokers and 15 nonsmokers; mean age, 23.7 +/- 2.6 years), healthy, trained subjects, were assessed before and after a standard maximal exercise test.


RESULTS
Exercise led to increased protein oxidation (carbonyl assay) in both smokers (+17.7%, P < 0.001) and nonsmokers (+19.1%, P < 0.05), elevation in plasma conjugated dienes (+ 157%, P < 0.04), and plasma lipid peroxides (+14%, P < 0.059) in smokers versus nonsmokers after exercise. Plasma antioxidants levels were significantly lower in the smoking group, with reduction in total carotenoids (-36.5%, P < 0.001), vitamin A (-80%, P < 0.001), and vitamin E (-64%, P < 0.002), compared with nonsmokers. A significant rise in leakage of muscle enzymes (CPK, LDH) and urine proteins (microalbumin and myoglobin) occurred in all subjects after exercise. CRP levels were higher in smokers compared with nonsmokers before and after exercise.


CONCLUSIONS
Our results suggest that unnoticed interaction exists between smoking and intense exercise, which indicates that smokers are more susceptible to oxidative insults probably due to lower antioxidant capacity.
Gochman
Einat
E
Department of Anatomy and Cell Biology, Rappaport Faculty of Medicine, Technion-Israel Institute of Technology, Haifa, Israel.
Reznick
Abraham Z
AZ
Avizohar
Ophir
O
Ben-Amotz
Ami
A
Levy
Yishai
Y
D000328:Adult; D000418:Albumins / Q000378:metabolism; D000818:Animals; D000975:Antioxidants / Q000378:metabolism; D002338:Carotenoids / Q000097:blood; D015444:Exercise; D006801:Humans; D008054:Lipid Peroxides / Q000097:blood; D008055:Lipids / Q000097:blood; D008297:Male; D009211:Myoglobin / Q000378:metabolism; D010084:Oxidation-Reduction; D018384:Oxidative Stress; D050050:Protein Carbonylation; D012907:Smoking / Q000009:adverse effects*; D014801:Vitamin A / Q000097:blood; D014810:Vitamin E / Q000097:blood
D000418:Albumins; D000975:Antioxidants; D008054:Lipid Peroxides; D008055:Lipids; D009211:Myoglobin; D014801:Vitamin A; D014810:Vitamin E; D002338:Carotenoids