If you pick up any fitness magazine or walk into any nutrition store you will find dozens of products that claim to improve performance, with more showing up on the store shelves every month. In most cases the claims are exaggerated with very few products actually improving performance. Every now and then however a product does come along that lives up to the hype; about twenty years ago that product was creatine, which has gone on to become the most researched performance enhancing supplement with the vast majority of studies supporting it’s use in most athlete groups. Recently another product has started to show that same type of promise: Beta alanine. Beat alanine supplementation has been reported to decrease fatigue associated with higher intensity exercise.
Fatigue during Exercise
Fatigue, defined as the inability to carry on a given level of work, is a complex phenomenon with many factors contributing simultaneously. While the inability of the nervous system to activate muscle fibres, interference with calcium release or uptake within the muscle, structural damage to muscle fibres, heat, and depletion of energy stores are some of the main culprits, an accumulation of metabolites like ADP, inorganic phosphate, lactate and hydrogen ions are among the most well known contributors to fatigue.
There has been an ongoing debate about the role of lactate in fatigue. Research conducted in the 1970s suggested that lactate was a major contributor to fatigue. Many of these studies were correlation studies that did not look at cause and effect. While there was a correlation between the amount of lactate that was produced and fatigue more recent research has shown that lactate itself does not contribute to fatigue and may actually work to prevent fatigue. The production of hydrogen ions, from various sources in the series of chemical reactions that take place when the anaerobic energy systems are used, can lead to a decrease in the pH of the cell; interfering with energy production and muscle contraction.
Buffers are the body’s chemical agents that keep pH in the cells within normal range. There are a variety of buffers that the body uses. Bicarbonate is the most important extracellular buffer, meaning that it maintains the pH outside of the cells. It has been known for many years that ingesting sodium bicarbonate, baking soda, can increase the effectiveness of the bicarbonate buffering system in the body and delay fatigue in high intensity sports. For many people ingesting baking soda causes stomach problems and can lead to vomiting or diarrhoea, unpleasant side effects at the best of times but particularly problematic during competition. Carnosine is the primary intramuscular buffer found in humans, it also seems to have positive effects on the nervous system, acts as an antioxidant and may have anti aging effects. Carnosine does not appear to be increased by exercise but supplementation with Beta Alanine does increase intramuscular carnosine and improve buffer capacity.
Effects on Performance
The majority of studies suggest that beta alanine can enhance performance in sports where there are maximal or near maximal efforts for 60s to 5 minutes. Shorter duration sprints and strength training do not seem to benefit as much from beta alanine use, although total work volume in strength training sessions can be improved by as much as 20% following beta alanine supplementation. Whether the increase in work volume can translate into better training adaptations and performance improvements is not known. Two studies have shown improvements in power at anaerobic threshold following beta alanine supplementation and slight improvements (2.5%) in time to exhaustion at anaerobic threshold.
Several studies have been done on to find the optimal protocol for taking beat alanine. It appears that ability of beta alanine to increase carnosine is dose dependant, 6-7 g per day give best results. Beta alanine supplements often cause tingling sensations in various parts of the body, particularly in the head and neck region. This can become quite intense and unpleasant if large doses are taken at one time. The tingling can start within minutes of taking the supplement and last for up to an hour. Smaller doses spread throughout the day or time release capsules seem to decrease or eliminate the tingling. Beta alanine supplementation is not an acute response supplement it needs to be done over an extended period of time for significant effects to be noticed, usually 28 days or more.
Currently the only known adverse effects associated with beta alanine supplementation is the tingling that is noticed shortly after taking the supplement.
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