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theses

Theacrine (1,3,7,9-tetramethyluric-acid) is a pure alkaloid with a similar structure to caffeine and acts comparably as an adenosine receptor antagonist. Early studies have shown non-habituating effects, including increases in energy, focus, and concentration in Teacrine®, the compound containing pure theacrine. PURPOSE: to determine and compare the effects of Teacrine® and caffeine on cognitive performance and time-to-exhaustion during a simulated soccer game in high-level male and female athletes. METHODS: Elite male and female soccer players (N=24; MAge=20.96±2.05y, MMaleVO2max=55.31±3.39mL/O2/kg, MFemaleVO2max=50.97±3.90mL/O2/kg) completed a simulated 90-min soccer match protocol on a treadmill, with cognitive testing including simple reaction time (SRT); choice-RT during a go/no-go task (CRT); and complex-RT during a dual task of go/no go (COGRT) with distraction questions at halftime, and end-of-game. End-of-game testing was followed by a run to exhaustion at 85% VO2max. Participants completed four sessions in randomized order ingesting either 275mg teacrine (TCr), 275mg caffeine (Caf), 125/150mg teacrine+caffeine (TCr+Caf), or placebo(P) 30 min prior to the match. Time of day and pre-exercise nutrition were controlled. RM-MANOVAs with univariate follow-ups were conducted and significance was set at P<0.05. RESULTS: Time-to-exhaustion trended toward improvements in all conditions when compared to placebo (ESTCr=0.43, ESCaf=0.41, ESTCr+Caf=0.51). There was a condition main effect (P<0.05) in which Caf (0.595±0.054s) and TCr+Caf (0.590±0.059s) improved CRT compared to P (0.608±0.067s). There was a significant Time main effect for COGRTWrong, with improved accuracy at post compared to mid (16.46±2.02 vs. 19.20±2.13). A Time main effect also occurred for SRT, with better RT at mid compared to post (0.639±0.054s vs. 0.646±0.054s). However, a Time x Condition interaction (P<0.05) revealed that P improved from mid to post instead (0.646±0.064s vs. 0.632±0.049s). CONCLUSION: The 27-38% improvements in time-to-exhaustion reflect an increased performance capacity with these supplements that may have important implications for “added time” scenarios. The larger improvement in choice-RT from TCr+Caf may be due to overlapping peak times for the supplements, leading athletes to sustain greater focus under fatigue for longer periods compared to the other conditions. Peak times may also play a role as the largest SRT improvements occurred at mid compared to post-game; perhaps a higher dosage would cause less of a decline during the transition between Caf and TCr. The improvement seen in accuracy post-game may indicate a training effect for allocation of resources toward the end of a game when players need greater concentration.

ETD_9376

M.S.

Includes bibliographical references

by Marissa Bello

doi:10.7282/t3-7xhk-3r08

ETD graduate

The author owns the copyright to this work.