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SUMMARY
BETA-ALANINE SUPPLEMENTATION HAS BEEN FOUND TO INCREASE INTRAMUSCULAR CARNOSINE, STRENGTH, POWER, VOLUME PER TRAINING SESSION AND A HOST OF OTHER INDICES OF AEROBIC AND ANAEROBIC CAPACITY. HOWEVER, THERE IS A NEED TO SYNTHESIZE THIS RESEARCH SO THAT THE ATHLETE AND STRENGTH COACH ALIKE CAN OPTIMALLY BENEFIT FROM BETA-ALANINE SUPPLEMENTATION. THE PURPOSE OF THIS REVIEW IS TO PROVIDE AN ANALYSIS OF STUDIES CONDUCTED ON BETA-ALANINE. THE REVIEW WILL COVER THE OPTIMAL DOSAGE OF BETA-ALANINE; ITS USE IN RESISTANCE TRAINING, INTERMITTENT, AND ENDURANCE-BASED EXERCISES; AND WHEN COMBINED WITH CREATINE IN TRAINED AND UNTRAINED INDIVIDUALS.
KEY WORDS:
beta-alanine; carnosine; contraction/physiology; musde strength/physiology; muscle/skeletal physiology; beta-alanine administration and dosage pharmacokinetics; carnosine metabolism; dietary supplement
The human body is endowed with the capacity to adapt to training; such that it can maintain low to moderately high contractions for extended periods. For example, the world record marathon time is 2:03:59 run by Haile Gebrselassie of Ethiopia. At the opposite end of the spectrum, strength and power athletes can exert extreme torques and forces such that today a 1,000 Ib back squat is no longer unthinkable in the world of powerlifting. In between these extremes lie sports such as hockey, basketball, and speed skating, which require brief intermittent bouts of highintensity activity. Although the time to fatigue differs among categories of activities, the end result of each are declines in force generating capacity and ultimately impairments in performance. While fatigue is characterised by a decrease in energy stores (adenosine triphosphate. phosphocreatine, and glycogenic substrates) and the intracetlular accumulation of metabolites (adenosine diphosphate, inorganic phosphate, hydrogen ions [H+], and magnesium), 2 priman' mechanisms thought to underlie fatigue include the accumulation of H* ions and oxidative stress. An acute accumulation of H"1 results in a decrease in intramuscular pH, which may contribute to fatigue in some models of exercise. Chronically, intense training can stimulate oxidative stress, with both excess H+ and oxidative stress demonstrating to impair excitation-contraction coupling (EC coupling) processes, leading to reported decrements in force.
An athletes' ability to resist fatigue may determine the intensity and duration of their training and ultimately dictate performance outcomes. Resistance to fatigue is thought to be limited, in part, by intramuscular concentrations of carnosine (29). Carnosine appears to enhance fatigue resistance by a...