GU: Learn the Science
The world's first energy gel is still the most efficient source of premium fuel available to athletes today. The original idea behind GU was to find the quickest way to deliver an appropriate amount of calories to an athlete during competition without upsetting his or her stomach. Since then, the formula has been tweaked and upgraded to take advantage of feedback from GU's elite athletes and the latest scientific discoveries. In addition to supplying the body with high-quality calories and electrolytes to keep it going, GU mitigates the energy-sapping effects of lactic-acid build-up, optimizes energy production, aids recovery by replenishing muscle glycogen stores and allows for greater mental focus through delayed onset of fatigue signals from the central nervous system. Yep, that's all in one packet of GU.
Maltodextrin & Glucose: GU's Carbohydrate Formula for Success
GU provides athletes with a shot of 100 calories in the form of 70-80% maltodextrin and 30-20% fructose (The ratio depends upon the flavor.). Why maltodextrin? It's a complex carbohydrate, and studies have shown that some complex carbs are actually digested faster than simple sugars like table sugar and honey. This matters because the quicker your body can tap these carbs, the less blood needs to be diverted away from your muscles to the stomach to digest them. This benefit also comes into play during recovery, as a packet of GU eaten just after exercise goes straight to work replenishing your muscle glycogen stores - the energy source first tapped by the body during intense physical exertion. Fructose is the principle sugar in fruit, and we use it because your stomach processes it faster than the maltodextrin, yet it doesn't produce a sugar high like you experience with simple sugars. We don't use more fructose because too much of it can upset your stomach and draw precious blood away from your muscles. Fructose also enhances the flavors - it's what makes you crave GU. But we don't make it too sweet. That's because studies have shown that our mouths become highly sensitive to sweet tastes after extensive exercise. As a result, what tasted sweet at the beginning of exercise will, two-plus hours later, taste overly sweet and become unpalatable. GU, on the other hand, will taste perfect, which means you'll continue to eat and keep your body fueled.
GU Amino Acid Blend: Puts the "Long"¯ in "Longer"¯
In addition to continuously resupplying your body with fuel, GU features a unique blend of amino acids to combat muscle fatigue, accelerate the conversion of carbohydrates into usable energy, and maintain mental focus.
When you stress your muscles, they fatigue and experience a rather unpleasant side-effect, metabolic acidosis (a.k.a., "the burn"). Both are primarily due to proton (H+) build-up1. In our research, we found studies2 that demonstrate how various naturally occurring proteins packed with histidine have buffered the muscles' acid build-up. That's because the histidine residues contained within these proteins are able to neutralize those nasty H+ ions, and therefore reduce the effects of acidosis. By adding histidine, we're encouraging the body to produce more of these buffering proteins and keep your muscles pumping harder longer. Also, the less damage done to your muscles, the faster they recover.
Citrates (potassium citrate, sodium citrate, and citric acid):
During physical exertion, the body requires energy to keep moving. Central to the production of energy is the citric acid cycle (Krebs cycle), which is responsible for the breakdown and processing of amino acids, glucose, and fatty acids into ATP3, the actual energy molecule that fuels your muscles. GU's citrate blend contributes to the citric acid cycle and promotes greater efficiency in the production of ATP. Why? Because the faster you can produce ATP, the sooner your muscles can use it.
Branched Chain Amino Acids (BCAA-leucine, valine and isoleucine):
When your heart and muscles are working hard, BCAAs become a major fuel source in addition to promoting protein synthesis - the converting of protein into fuel- as well as setting the table for rapid glucose biosynthesis3,4. GU's BCAAs also thwart muscle catabolism, a distressing natural situation where the body starts breaking down its own muscle to use as fuel. In addition, research5 suggests that BCAAs supplementation may delay the onset of central fatigue by blocking the transport of tryptophan into the brain, thus limiting the production of serotonin. This key neurotransmitter has been linked to depression of the central nervous system function which leads to feelings of sleepiness and fatigue6. By blocking this effect, GU helps you stay more alert and on top of your game.
Two C's (Calcium and Caffeine) for High Performance:
We put calcium into each packet of GU because you lose calcium during exercise, and your body needs it to thrive. Research has shown that there may be a link between muscle fatigue and calcium loss, so adding it back to your body is a good thing.
GU uses 20mg of caffeine (Strawberry Banana and Lemon Sublime have none, while Espresso Love has 40mg of the stuff) for two reasons: It acts as a stimulant - let's call this the caffeine-kick effec - and it helps the body metabolize fat during exercise, providing the body with an additional fuel source. 20mg is an ideal amount of caffeine to keep you alert and burning fat without getting a case of the jitters. The extra caffeine in Espresso Love is there for those days you really, really need help jump starting your workout.
GU's Antioxidant Blend: Saving You from Yourself
Each packet of GU comes with a healthy dose of vitamin C and vitamin E (how much depends on which flavor you choose). They're there because antioxidants provide a defense system against free radical damage to muscle tissues caused by the increased oxygen (oxidation) found in working muscles7. They won't boost your performance, but they protect against the muscle tissue damage that comes from a hard workout.
GU's Herbal Blend: A Little Homeopathic Love to Make Life Easier
Towards the end of GU's ingredient list is its Herbal Blend comprised of chamomile, a natural anti-inflammatory, and ginger, which naturally soothes the stomach as it quickly goes to work digesting the contents of each packet of GU.
And that's it. Everything inside each packet of GU is engineered to do one simple thing: provide your body with the essential requirements it needs to keep going for miles and miles and hours and hours. It goes down easy, and it goes to work fast so you donā€™t have to slow down.
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