Performance Enhancing And Pro Regenerative Effects Of Alpha Lipoic Acid Supplementation After Acute And Chronic Resistance And Endurance Training.

Abstract

PURPOSE: Oxidative stress is an important key player in the initiation of training induced adaptations but also a risk factor with respect to over training and lack of regeneration. Alpha lipoic acid (ALA) has been described to be a powerful antioxidant. Therefore it was the aim of this study to investigate the effects of acute and chronic ALA supplementation on the regeneration and performance of athletes after intensive exercise. METHODS: In this double-blinded, randomised, controlled trial in cross-over design, 17 male resistance and endurance-experienced athletes successfully participated. The subjects were divided into two groups (ALA and Placebo) and underwent a standardized acute (3sets back squats of 12 reps each and 3 sets of low jumps with 15 reps each) and chronic training protocol (6 days of intensive resistance and endurance training). Between the acute and chronic training experiments was a 4-week break. At certain time points before and after exercise (T0, T1 (+24h) and T2 (+7d)) blood samples were taken and the concentrations of muscle damage (creatine kinase, myoglobin), inflammation (interleukin 6 and 10) and oxidative stress (ox LDL) markers were investigated. In addition, the maximum performance in the back squat was measured at all timepoints. RESULTS: In the 6 day chronic training intervention a clear inhibition of muscle damage and inflammation could be observed in individuals under chronic supplementation of ALA compared to the control group. Whereas performance in the back squat was significantly reduced after 6 day of chronic training in the placebo group no significant loss of performance could be detected in the ALA group. In contrast after an acute training a single application of ALA did not result in significant differences between the placebo and ALA groups with respect to all before mentioned markers and back squat performance CONCLUSIONS: Based on these data we conclude that that ALA supplementation has only limited effects if given acute and directly after exercise but results in remarkably and significant pro-regenerative and performance enhancing effects after chronic supplementation. Mechanistically these effects seem to be mediated via a modulation of the immune response and less by antioxidative effects, which needs to be investigated in more detail in future investigations.