Week 10 - Buffering agents (NOT IN EXAM) (Beta-alanine) (Sodium bicarbonate) Flashcards
What is the background behind the use of buffering agents?
High rates of glycolysis during
maximal intensity exercise leads to
the accumulation of H+.
Fall in intramuscular pH from ~7.1
to <6.5 (blood pH decreases from
~7.4 to 7.1).
Acidosis inhibits glycolysis (PFK),
reducing ATP production, causing
fatigue.
Various buffers minimise shift in pH.
What is beta-alanine?
is a (non-essential) beta amino acid precursor of carnosine
What is carnosine?
- Where is it found?
- What does it have an important role in?
- What foods is it found in?
Carnosine is a dipeptide made up of two amino acids beta-alanine and histidine
- Carnosine is found in human skeletal muscle
- Has an important role as intracellular pH buffer
- Carnosine is found in red meat, chicken and fish and seafood.
How long is beta-alanine supplementation required to achieve meaningful increases in muscle carnosine levels?
4 weeks
True or False:
Diet alone is enough to increase muscle carnosine levels required for a performance benefit.
False - requires supplementation of beta-alanine
What forms are beta-alanine available in?
powder or tablet/capsule forms
- Slow release capsules can help to improve retention, further increasing muscle carnosine levels.
How does chronic beta-alanine supplementation improve performance?
Increases muscle carnosine levels which enhances intracellular buffering of H+ ions produced during anaerobic glycolysis.
Greater muscle buffering capacity can limit/delay fatigue and improve exercise performance when exercise is limited by muscle acidosis.
Describe the “loading dose” supplementation regime.
3.2 g beta-alanine/day for >8 weeks
OR
6.4 g beta-alanine/day for >4 weeks
Describe the “maintenance dose” supplementation regime.
1.2g beta-alanine/day
What are the benefits of consuming beta-alanine in split doses with meals?
enhanced uptake and better management of side effects
When should you consider the use of beta-alanine supplementation?
Short (30 sec to 10 min), sustained high-intensity sports e.g., rowing, track cycling, swimming, middle distance running.
In the weeks preceding a period of
training where training intensity is
prioritised, or before competition blocks.
Sports that involve repeated high-intensity efforts e.g., resistance training, team/field sports, racquet sports.
How can the response to beta-alanine vary between individuals?
Baseline muscle carnosine levels
- Athletes who follow a plant-based diet may have lower levels of muscle carnosine and therefore further room for improvment.
Training status
- Highly-trained individuals may experience smaller benefits from beta-alanine supplementation. However, this can still be worthwhile for athletes where small benefits can have a meaningful impact on sporting results.
What side effects can beta-alanine have?
Acute doses of instant release beta-alanine exceeding 800-1000mg can result i8n paraesthesia (tingling sensation, like pins and needles) on the skin that can last up to an hour and/or skin rashes.
What other important considerations are there with beta-alanine supplementations?
Economic cost: it requires a substantial investment given the long period of supplementation.
Inaccurate claims: inclusion of beta-alanine in common pre-workout supplements may contain an amount that is too small to have any effects on performance despite giving you a “buzz”.
What is the current recommended loading dose for beta-alanine?
3.2-6.4g of beta-alanine per day for >4-8 weeks