The Influence of Regular Exercise and Alpha Lipoic Acid Supplementation on the Superoxide Dismutase Activity in Human

[[abstract]]Abstract Purpose: To investigate the influence of regular exercise and antioxidant alpha lipoic acid (ALA) supplementation on superoxide dismutase (SOD) activity in human. Methods: Subjects were divided into four groups: (1) PN group: those who took placebo and had no regular exercise habits; (2) PE group: those who took placebo and had regular exercise habits; (3) AN group: those who took ALA and had no regular exercise habits; and (4) AE group: those who took ALA and had regular exercise habits. Ten male subjects in group with a total of forty subjects. Each subject had 2 exhausted exercise tests (Bruce protocol) and between the two tests, ALA or placebo was supplied. In each exercise test, in order to analyze SOD activity in blood cells, the blood samples were collected four times: (1) before the exercise; (2) at exhaustion; (3) 15 minutes after exercise; and (4) 30 minutes after exercise. Two-way ANOVA was used for statistical analysis. Results: In the first exercise test, at exhaustion and 15 minutes after exercise, SOD activity in red blood cells of those who had regular exercise habits (PE and AE) were significantly higher than those who had no regular exercise habits (PN and AN). For the second exercise test, at exhaustion, SOD activity of PE and AE were both significantly higher than that of PN and AN. Between the two exercise tests, performances and SOD activity showed no significant differences in each group. At exhaustion of the first exercise test, AE and AN showed no significant differences (p= .079). However, in the second exercise test, there were significant differences (p= .002) and the peak value of SOD activity of AE appeared at exhaustion, instead of 15 minutes after exercise. At exhaustion, SOD activity in the first exercise test was significantly higher than that in the second test (p= .035). Conclusions: For those who had regular exercise habits, two-week ALA supplementation had no additive effects, but it effectively increases SOD activity at exhaustion to counteract with oxidative stress. For those who had no regular exercise habits, SOD does not decrease significantly. This research reassures that regular exercise can effectively increase SOD activity and antioxidant capacity in human. The suggestion is that while taking antioxidant, regular exercise habit is necessary to increase human antioxidant capacity and increases SOD activity effectively to decrease damage from oxidative stress.