Week 11

Question 1

What form is creatine normally in?

Answer 1

Normally in a powdered form although coca cola released a drink version called powerade ultra last year.

Question 2

Creatine synthesis how does it occur?

Answer 2

Creatine is endogenously synthesized in the liver and kidney from arginine and glycine and creatine is mainly found in the muscle and the brain. 70% found as phosphocreatine and 30% as free creatine.

Question 3

Why is creatine important?

Answer 3

Phosphocreatine is important as it allows for rapid energy production.
ADP + PCR + H+ forms ATP and creatine- helps with ATP availability for metabolic work. Phosphocreatine also in its process of conversion to creatine consumes protons which decreases the muscle’s acidity.

Question 4

Creatine turnover

Answer 4

Creatine intake- 2 grams a day (1 grams endogenous, 1 grams dietary intake), 120 grams total body content (95% in muscle), creatine excretion - creatinine - urine - around 2 grams a day.

Question 5

Creatine sources

Answer 5

Red meat, supplements (eg.vegetarian ones etc.) , herrings

Question 6

How to get creatine into the muscle/ creatine loading

Answer 6

If you take creatine for a week can substantially increase creatine levels however if you stop taking creatine then values return back to around baseline. If you keep up small amounts of creatine loading after large amounts the first few weeks then you can help maintain higher creatine levels. If you hit smaller amounts for the a longer period of time you can still hit the same levels you would have done with the 7 days of high creatine loading.

Question 7

Phosphocreatine energy

Answer 7

Phosphocreatine energy does not last very long but generates energy very fast. You need some time to rebuild phosphocreatine stores.

Question 8

Creatine supplementation effects on mean power output

Answer 8

Creatine supplementation increased mean power output and increased sprint performance by 6 and 7% at 1 minute and 3 minutes rest though did not have an effect at 6 minutes rest. So found creatine does improve intermittent exercise as long as there is short intervals between sprints.

Question 9

Creatine strength training vs strength training and placebo for 6 weeks

Answer 9

Both groups improved strength though the creatine group improved strength a bit more and also increased lean mass by about 2kg- some of this may be water though as it can also increase water retention

Question 10

Would not generally associate creatine with endurance exercise as provides quick energy.

Answer 10

Used a loading period first and then checked the amount of creatine present in the muscle.
In terms of endurance performance found no significant difference between creatine and placebo- as endurance exercise does not generally rely on anaerobic systems such as the phosphocreatine system.

Question 11

Side effects of creatine-

Answer 11

Increases body mass by 1-3 kg- due to fluid retention within the skeletal muscle, increased FFM while using creatine still represents muscle.
Creatine has some reports of nausea or gastrointestinal distress however this can be decreased by consuming it with food or consuming in multiple smaller doses.
There is no evidence for creatine causing renal damage/failure, dehydration, cancer etc