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Evaluation of the Efficacy of Lactigo™ Topical Gel as an Ergogenic Aid

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Evaluation of the Efficacy of Lactigo™ Topical Gel as an Ergogenic Aid

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Sharpe TM, Macias CJ. Evaluation of the Efficacy of Lactigo™ Topical Gel as an Ergogenic Aid. JEPonline 2016;19(3):15-23. The purpose of this study was to investigate whether a novel topical carnosine preparation could affect anaerobic and potentially aerobic exercise performance. Eleven elite male soccer players (age, 22.47 ± 2.14 yrs; body weight, 84.2 ± 7.82 kg; height, 183.79 ± 4.5 cm; BF 6.90 ± 1.8%) with no previous use of LactiGo™ participated in this study. First, the subjects completed a Level 1 Yo-Yo intermittent recovery test designed to test maximal aerobic capacity. Second, they performed a series of all-out 3 x 1000 m runs requiring a robust anaerobic contribution. A 3-day washout was used between each exercise (Yo-Yo, 3 x 1000 m) and between each 3 x 1000 m series. After the initial application of LactiGo™ topical gel, a clinically significant improvement in distance traveled during the Yo-Yo intermittent recovery test (5.41% ± 4.80%, P=0.069) was observed along with a statistically significant reduction in time to complete the all-out 3 x 1000 m runs (4.13% ± 0.68%, P=0.036). The observed improvements in both tests after the initial application of LactiGo™ indicate a loading phase, commonly seen in buffering agents, is not required. The increase in aerobic and anaerobic work capacity evidenced after the use of LactiGo™ topical gel suggests that it could serve as an ergogenic aid.
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This study investigated whether carnosine alters individual processes involved in normal excitation-contraction (E-C) coupling in mammalian skeletal muscle fibres. Mechanically-skinned fibre preparations were utilized because they allow carnosine to be precisely and readily applied to the cytoplasmic environment as desired, whilst still retaining the normal E-C coupling mechanism. Carnosine caused an increase (approximately +0.02 to approximately +0.09 pCa units) in Ca2+ -sensitivity of the contractile apparatus in a concentration-dependent manner (i.e. with 4, 8 and 16 mM respectively). Force responses elicited by 8 mM caffeine-induced Ca2+ release from the sarcoplasmic reticulum (SR) were potentiated in the presence of carnosine (compared to the bracketing responses in the absence of carnosine). Force responses elicited by transverse tubular (T-) system depolarization via the dihydropyridine receptors (DHPRs), either by ionic (Na+) substitution or by action potentials (APs), were also potentiated in a concentration-dependent manner in the presence of carnosine. The potentiation of the force responses in all of the various experiments was seemingly totally explicable by the increase in Ca2+-sensitivity of the contractile apparatus caused by carnosine. Thus, these results show that carnosine potentiates force responses solely by 'sensitizing' the contractile apparatus to Ca2+ ions and under physiological conditions does not cause additional Ca2+ release from the SR.
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