Switch Nutrition Essentials Beta Alanine is a non-essential amino acid that combines with L-Histidine in the body to produce a di-peptide called Carnosine. Carnosine builds up in skeletal muscle after continual supplementation of Beta-Alanine and buffers H+ (Lactic Acid). NB: Histidine is not the limiting amino acid and supplementation doesn’t improve results. After 4 weeks of Beta-Alanine supplementation athletes experience greater than 50percent increase in Carnosine and after 10 weeks greater than 80percent increase. This allows for increased additional repetitions and improved athletic performance.