學生姓名:
蘇婉蘋
指導教授:
蕭泉源
學 號:
10332057
學期:
103下
摘 要:
Carnosine (β-alanyl-L-histidine) is a dipeptide with pH buffer properties, which is found in high concentrations in skeletal muscle. This report was to investigate the effects of β-alanine supplementation on muscle carnosine loading and exercise performance of mice and humans. Results indicated that the supplementation with 1.8% carnosine and 1.2% β-alanine for mice showed markedly higher muscle carnosine and anserine levels compared with control group. β-alanine supplementation (1.2%) resulted in increased fatigue resistance in the beginning of the fatigue protocol in soleus and a marked leftward shift of the force–frequency relation in EDL (10%–31% higher relative forces). The effects of β-alanine treatment (BA group) on combat specific performance in soldiers were investigated. A significant elevation in muscle carnosine content was noted in BA group compared to placebo group. Changes in carnosine content was correlated to changes in fatigue rate. The 30-days of BA ingestion can increase muscle carnosine content and improve aspects of military specific performance. The effect of meal and beta-alanine coingestion on muscle carnosine loading was also studied. Orally ingested slow-release BA has a very high whole body retention (97–98%) throughout supplementation period, nor is it influenced by the coingestion of macronutrients. Thus, a very small portion (1–2%) is lost through urinary excretion, and equally only a small portion is incorporated into muscle carnosine (~3%), indicating that most ingested BA is metabolized. Besides, the efficiency of carnosine loading in soleus is significantly higher when pure BA is coingested with a meal compared with in between the meals, suggesting that insulin stimulates muscle carnosine loading. In conclusion, β-alanine supplementation increases muscle carnosine content and the optimal timing is coingested with a meal.
10332057-2-蘇婉蘋-蕭泉源.pdf