Taurine: A Potential Ergogenic Aid for Preventing Muscle Damage and Protein Catabolism and Decreasing Oxidative Stress Produced by Endurance Exercise

The aim of this study was to evaluate the effects of taurine and chocolate milksupplementation on oxidative stress and protein metabolism markers, and aerobicparameters in triathletes. Methods: A double-blind, crossover study was conducted with 10 male triathletes,aged 30.9 +/- 1.3 year, height 1.79 +/- 0.01 m and body weight 77.45 +/- 2.4 kg. Threegrams of taurine and 400 ml of chocolate milk (TAUchoc), or a placebo (chocolate milk)(CHOC) was ingested post exercise for 8 weeks. Oxidative stress marker levels, and 24 hurinary nitrogen, creatinine, and urea excretion were measured before and after 8 weeksof training and supplementation with TAUchoc or CHOC. A maximal incremental runningtest on a treadmill was performed in order to evaluate aerobic parameters: Vmax, heartrate (HR) and rate of perceived exertion (RPE). Results: TAUchoc treatment during the 8 weeks resulted in increased taurine plasmalevels (PRE 201.32 +/- 29.03 mu mol/L and POST 234.36 +/- 35.51 mu mol/L, p=0.01),decreased malondialdehyde levels (19.4%, p=0.03) and urinary nitrogen excretion(-33%, p=0.03), and promoted positive nitrogen balance (p=0.01). There wereno changes in reduced glutathione (TAUchoc PRE 0.72 +/- 0.08 mmol/L and POST0.83 +/- 0.08 mmol/L; CHOC PRE 0.69 +/- 0.08 mmol/L and POST 0.81 +/- 0.06 mmol/L),vitamin E plasma levels (TAUchoc PRE 33.99 +/- 2.52 mu mol/L and 35.95 +/- 2.80 mu mol/Land CHOC PRE 31.48 +/- 2.12 mu mol/L and POST 33.77 +/- 3.64 mu mol/L), or aerobicparameters, which were obtained in the last phase of the maximal incremental runningtest (Vmax TAUchoc PRE 13 +/- 1.4 km/h and POST 13.22 +/- 1.34 km/h; CHOC PRE13.11 +/- 2.34 km/h and POST 13.11 +/- 2.72 km/h), the heart rate values were TAUchocPRE 181.89 +/- 24.18 bpm and POST 168.89 +/- 46.56 bpm; CHOC PRE 181.56 +/- 2.14bpm and POST 179.78 +/- 3.4 bpm, and the RPE were TAUchoc PRE 8.33 +/- 2.4 AUand POST 9.1 +/- 2.1 AU; CHOC PRE 8.11 +/- 4.94 AU and POST 8.78 +/- 2.78 AU). Conclusion: Taurine supplementation did not improve aerobic parameters, but waseffective in increasing taurine plasma levels and decreasing oxidative stress markers,which suggests that taurine may prevent oxidative stress in triathletes