The effect of acute taurine ingestion on 4-km time trial performance in trained cyclists.

Ryan Ward,Lars R Mcnaughton,Craig A Bridge,S Andy Sparks

doi:10.1007/s00726-016-2282-4

Abstract

Taurine (TAU) has been shown to improve exercise time to exhaustion and 3-km running performance; however, no studies have considered the effect of acute TAU ingestion on short duration cycling time trial (TT) performance. The aim of this study was to determine the effects of a single oral acute dose of 1000 mg of TAU on a laboratory simulated 4-km cycling TT. Eleven trained male cyclists performed three, 4-km TTs. The first of the trials was a familiarisation, followed by two subsequent trials which were performed two hours after the consumption of either 1000 mg of TAU or placebo (P), using a double-blind randomised crossover design. Capillary blood samples were obtained prior to the start and immediately after each TT for the measurement of lactate, pH and HCO3 −. There was no effect of TAU (p = 0.731, d = 0.151) on performance (390 ± 27 and 388 ± 21 s for TAU and P, respectively), nor were there any condition main effects for VO2, lactate, pH, or HCO3 − (p > 0.05) despite post TT changes in lactate (7.3 ± 2.5 mmol l−1, p < 0.001, d = 2.86, 7.6 ± 2.0 mmol l−1 p < 0.001, d = 3.75); pH (−0.255 ± 0.1, p < 0.001, d = 2.62, −0.258 ± 0.09, p < 0.001, d = 2.87); HCO3 − (−13.58 ± 2.7 mmol l−1, p < 0.001, d = 5.04 vs. −13.36 ± 2.3, p < 0.001, d = 5.72 for TAU and P, respectively). The findings of this study suggest that a pre-exercise dose of 1000 mg TAU offers no performance advantage during 4-km TT nor does it alter the blood buffering responses in trained cyclists.

Highlights

Taurine (TAU) plays a role in a wide variety of physiological functions and is found in many tissues (Schaffer et al 2010)
The aims of the present study were (1) to determine the effects of an ecologically relevant acute oral dose of TAU, on a laboratory simulated 4-km cycling time trial (TT) performance in trained cyclists and (2) to determine the effects this ingestion strategy has on blood acid– base responses
There were no statistical differences in overall performance time (Fig. 1) either between the familiarisation trial and the P trial nor as a result of TAU ingestion

Summary

Introduction

Taurine (TAU) plays a role in a wide variety of physiological functions and is found in many tissues (Schaffer et al 2010). It has been suggested that TAU plays a role in aerobic exercise (Ward et al 1999) and mitochondrial function (Hansen et al 2010) since higher concentrations have been reported in the skeletal muscle of trained (~64 mmol kg−1 dw) vs untrained (~50 mmol kg−1 dw) participants (Graham et al 1995). In spite of there being some suggestions relating to the function of TAU, it remains unclear how different skeletal muscle fibre types might be affected either intra- or extracellularly by supplementation. It is unclear how TAU supplementation might affect exercise performance in activities which recruit different proportions of either type I or type II fibres. The lack of observed increases in skeletal muscle TAU content with supplementation, suggest that it is the alterations to extracellular TAU concentration that may explain the previously reported performance improvements following acute ingestion (Balshaw et al 2013)

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Discussion

Conclusion