Leucine | TheFinalSprint.com - Track & Field, Marathons, Racing News, Training Advice, Elite Athlete Blogs, Interviews, Podcasts, Videos and More!

Lead Stories: Monday, December 1, 2008

Does leucine effectively increase endurance? Is it safe?

Posted February 19th, 2007 at 8:00 AM by Hariz Siddiqui

Section: Nutrition, Supplements

A study from Australia showed that leucine helps athletes exercise longer (European Journal of Applied Physiology, August 2006), so now athletes are lining up to waste their money on supplements that are no more effective than any other source of sugar.

Leucine is a branched chain amino acid that the liver readily converts to sugar. Your body needs extra sugar during endurance exercise, and it doesn’t care where it gets it. Your brain gets more than 95 percent of its energy from sugar in your bloodstream. It cannot store extra fuel in its cells.

However, there is only enough sugar in your bloodstream to last three minutes. To prevent blood-sugar levels from dropping, your liver constantly releases sugar from its cells into your bloodstream. There is only enough sugar in your liver to last up to 12 hours at rest, and you run out of liver sugar much faster than that when you exercise.
Read the rest of this entry »

Comment on this post | Permalink

Supplements Made Easy - Part 3

Posted October 26th, 2006 at 12:15 PM by Jonathan Faccone

Section: Nutrition, Supplements

This is Part 3 in my “Supplements Made Easy” Seriesfor runners and other endurance athletes. Make sure to also go back and read Part 1 and Part 2!

Shopping for supplements can be a daunting task, but remember to keep it simple and that supplementation will only help if you first help yourself by doing your best in giving your body what is needs via your food intake.

Once you have taken care of proper eating, you can move onto supplements. Keep in mind, everyone’s body is different and therefore supplementation choices that you pick should be as unique as yourself.

BCAA (Branched chain amino acids) include the leucine, isoleucine, and valine. They are essential for aerobic metabolism and may have performance enhancing qualities for endurance events lasting longer then three hours. Lack of BCAA’s during endurance events could accelerate the breakdown of muscle glycogen and cause premature muscle fatigue.

Glutamine is the most abundant amino acid found in the body and is usually used for strength training as a muscle recovery agent, but may benefit endurance athletes as well. Evidence has shown that in times of stress, like exercise, the body cannot produce enough of this amino acid. This has been shown to contribute to muscle breakdown, diminished immune function and reduced performance.

Supplementation with 6-8 grams/day of BCAA and glutamine has been shown to decrease protein degradation during ultra-distance triathlon competition, decrease exercise induced muscle damage after prolonged running, and has shown to improve performance in 40K cycling time trial performance Read the rest of this entry »

One comment, add yours | Permalink