Koffein og jakten på mer energi!

[Vegard L]

Ps! Kanrnitin kan ha en gunstig effekt på fettstoffskiftet.

tyrosinen kan også virke lett inn på stoffskiftet (skjoltsbukskjertelen).

Karnitin er en aminosyre som er viktig for å bringe fettsyrene inn i mitokondriene for å forbrennes. Derfor trodde man at tilskudd av karnitin ville øke mengden intracellulært karnitin og dermed øke fettforbrenningen. Dette viste seg å ikke stemme, og tilskudd av karnitin er rimelig bortkastede penger om dette er målet.

I boken Modern Nutrition: In Health and Disease, side 1735, kan du lese:

However, research and detailed reviews of the available research did not support an ergogenic effect of L-carnitine supplementation on fuel utilization during exercise, maximal heart rate, anaerobic threshold, VO2-max, time to exhaustion in various anaerobic or aerobic exercise tasks, performance in either a marathon or a 20-km run, or body composition (211-214)

Kildene det refereres til er følgende:

211: Supplemental carnitine and exercise. [Am J Clin Nutr. 2000] - PubMed - NCBI

these studies suggest that carnitine supplementation does not improve maximal oxygen uptake or metabolic status during exercise in healthy humans

212: Carnitine and physical exercise. [sports Med. 1996] - PubMed - NCBI

However, the following arguments derived from established scientific observations may be forwarded: (i) carnitine supplementation neither enhances FA oxidation in vivo or spares glycogen or postpones fatigue during exercise. Carnitine supplementation does not unequivocally improve performance of athletes; (ii) carnitine supplementation does not reduce body fat or help to lose weight; [...]

[...]Although there are some theoretical points favouring potential ergogenic effects of carnitine supplementation, there is currently no scientific basis for healthy individuals or athletes to use carnitine supplementation to improve exercise performance.

213: Carbohydrate supplementation, glycogen depletio... [Am J Physiol. 1991] - PubMed - NCBI

214: Long-term administration of L-carnitine to hu... [Clin Chim Acta. 2002] - PubMed - NCBI

CONCLUSIONS:

Long-term oral treatment of healthy adults with L-carnitine is not associated with a significant increase in the muscle carnitine content, mitochondrial proliferation, or physical performance. Beneficial effects of the long-term treatment with L-carnitine on the physical performance of healthy adults cannot be explained by an increase in the carnitine muscle stores.

Eller det korte svaret som Asle Bøe skrev - karnitintilskudd er ikke vist å ha gunstig effekt på fettstoffskiftet

[neigutten]

The Vegard has spoken