Aim: 

Since physical exercise upgrades free radical generation, our aim was to investigate the enzymatic activity of superoxide dismutase (SOD), glutathione peroxidase (GPX), reductase (GRD) and catalase (CAT) after several cycloergometric protocols.

Methods: 

Twenty eight healthy males aged 23.20.7 years old and with a maximum oxygen uptake (VO_2max): 49.72,6mL/Kg/min were involved in this study. All participants were informed and statements of consent were signed. The subjects underwent 3 cycloergometric tests: The first to calculate VO_2max during continuous progressive physical effort; the second, a strenuous test until exhaustion, and the third an intensity corresponding to 70% of VO_2max for 30 minutes. Blood samples were taken from the antecubital vein just before (A) and immediately after the 3 tests (B, C, D). Plasmatic enzymatic activities were determined by the absorbance changes in a Beckman DU 800 spectrophotometer under their specific wavelength. Results were indicated in International Units (UI).

Results: 

An increase in all the following enzymatic activities was detected after physical exercise. (SOD: A=0.0180.01UI; B=0.0230.01UI; C=0.0270.01UI; D=0.0320.01UI, p<0.1) (GPX: A=0.9420.02UI; B=1.0250.03UI; C=1.0090.03UI; D=1.0170.03UI, p<0.05) (GRD: A=0.0210.002UI; B=0.0310.003UI; C=0.0320.003UI; D=0.0260.003UI, p<0.05) (CAT: A=38.73.2UI; B=54.94.5UI; C=102.77.1UI; D=60.64.9UI, p<0.05).

Conclusion: 

Physical activity causes overproduction of free radicals and however improves total antioxidant activity in the blood. The rise in SOD, GPX, GRD and CAT activity may contribute to the improvement of total antioxidant activity in the human plasma.

This study was sponsored by the Gobierno de Aragón (B40, Fisiología del Envejecimiento y del Estrés Oxidativo)