Changes in muscle carnosine of subjects with 4 weeks supplementation with a controlled release formulation of beta‐alanine (Carnosyn™), and for 6 weeks post

Abstract

Muscle Carnosine (M‐Carn) synthesis is limited by the availability of ?‐Alanine ( ?‐Ala) but can be increased by supplementation with ?‐Ala. This is of interest to athletes since increased levels of muscle M‐Carn have previously been shown to improve exercise performance. Above 10mg/kg bwt, however, ?‐Ala in solution or rapidly‐dissolving capsules causes symptoms of paraesthesia, despite the amount being less than that available from normal meat ingestion.PURPOSETo investigate the change in M‐Carn in subjects supplemented with a controlled‐release ?‐Ala formulation.METHODSeven males received 2x800mg ?‐Ala controlled release tablets, 4/d for 4w. Controlled release tablets were Carnosyn(tm) supplied by Collegiate Sports Nutrition. A muscle biopsy from the vastus lateralis was taken at 0 and 4w, and 3 and 6w post supplementation. No control group was included as several previous studies have demonstrated no change in M‐Carn without ?‐Ala supplementation.RESULTSSubjects did not experience paraesthesia. Mean (±SD) M‐Carn at 0 and 4w, and, 3 and 6w post supplementation were 25.9±4.3, 41.3±5.5, 38.3±6.7 and 35.4±5.5 mmol.kg−1 dry muscle. Post supplementation M‐Carn declined via first‐order kinetics with a half‐life (t½) determined to be 8.6w.CONCLUSIONThe controlled release ?‐Ala formulation was effective in raising M‐Carn. Following supplementation, levels of M‐Carn declined slowly with a t½ ~9w.