Buffering agents (beta-alanine) (NOT IN EXAM)

Question 1

Background - what does high rates of glycolysis during maximal intensity exercise lead to?

Answer 1

H+ accumulation = fall in intramuscular pH from ~7.1 to <6.5 (blood pH decreases from ~7.4 to 7.1)

Question 2

What effect does acidosis have on glycolysis?

Answer 2

Acidosis inhibits glycolysis (PFK),
reducing ATP production, causing
fatigue.

Various buffers minimise shifts in pH.

Question 3

What is beta-alanine?

Answer 3

A beta amino acid precursor of CARNOSINE (which is a dipeptide made of of 2 amino acids beta-alanine and histidine).

Question 4

Where is carnosine found and what is its role?

Answer 4

Found in human skeletal muscle, which has an important role as intracellular pH buffer.

Carnosine is found in red meat,
chicken and fish and sea food.

Question 5

Is dietary carnosine enough to enhance performance benefits?

Answer 5

No - beta-alanine supplementation is required for at least 4 weeks to achieve meaningful increases in muscle carnosine levels.

Question 6

Evidence - what is the % performance benefits ?

Answer 6

~2-3% during both continuous and intermittent high-intensity exercise
tasks ranging from 30 s to 10 min in duration

Question 7

Supplementation regime - What is the maintenance dose?

Answer 7

1.2g b-a/day

Consuming in split doses with meals can enhance uptake and cause better management of side effects

Question 7

Supplementation regime - What is the loading dose?

Answer 7

Either…
- 3.2g b-a /day for >8 weeks
OR
- 6.4g g-a/day for >4 weeks

Question 7

When should you consider taking carnosine?

Answer 7

• 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.

Question 8

How does the individual response to carnosine vary?

Answer 8

• Athletes who have lower levels of muscle carnotine may have more room for improvement.
• Highly-trained individual may experience smaller benefits from b-a supplements.

Question 9

What are the potential side effects of beta-alanine supplementation?

Answer 9

Acute doses of instant release beta-alanine exceeding 800-1000mg can result in paraesthesia (tingling sensation, like pins and needles) on the skin that can last up to an hour and/or skin rashes.

Question 10

Other than side effects, what are other important considerations?

Answer 10

Economic cost - requires substantial investment given the long period of supplementation.

Inaccurate claims - Inclusion of b-a in common pre-workout supplements may give you a ‘buzz’ - but the amount is generally too small to have any performance effects.