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Product Detail & Benefits


The Anti-Fatigue Caps Formula:

Potassium/Magnesium Aspartate - A well-known nutritionist says it best regarding aspartic acid, "Because aspartic acid increases stamina, it is good for fatigue and plays a vital role in metabolism. It is good for athletes and helps to protect the liver by aiding in the removal of excess ammonia." Studies (Agersborg and Shaw 1962, Hicks 1964, Gaby 1982) show this combination provides substantial benefit to the prevention of fatigue. Aspartic acid also combines with other amino acids to form molecules that absorb toxins and remove them from the bloodstream, aids the function of RNA and DNA, and helps to protect the liver. Additionally, the potassium/magnesium aspartate compound increases production of a key substrate, oxaloacetate, which is involved in energy production.

OKG - Both ornithine and alpha-ketoglutarate (OKG) provide a readily available, non ammonia-producing source of glutamine in the body. Glutamine is depleted at high rates during exercise but cannot be replaced with regular glutamine as it creates excess ammonia on its own. OKG increases the amount of glutamine in the muscle and also helps prevent muscle catabolism. Another well-known nutritionist writes, "Both ornithine and alpha-ketoglutarate act in the body as an ammonia scavenger."


Extra Benefits:
Although Anti-Fatigue Caps is designed primarily for ammonia reduction in long distance events, the nutrients in the formula are excellent for helping counteract everyday fatigue.

Thoroughly tested over several years in the most extreme athletic endurance events, Anti-Fatigue Caps helps remove fatigue-causing, performance-robbing ammonia. During extended endurance exercise the body accumulates excess ammonia from protein metabolism, which interferes with glycogen production, disrupting energy output. Anti-Fatigue Caps is a one-of-a-kind supplement combining two well-known ammonia-scavenging nutrients. Clean up the waste products of combustion, or you'll pay the price. To stay strong in multi-hour events, you need Anti-Fatigue Caps.


  • Potent aspartate compound, yielding significant amounts of potassium and magnesium.
  • 10 mg per capsule of EES™ (blend of protease and phytase enzymes) for greater absorption and assimilation of the key nutrients in Anti-Fatigue Caps.
  • All vegetable (VCaps™) capsules.

Nutrition Labels:

Anti-Fatigue Caps
Supplement Facts
Serving Size 2 Capsules
Amount Per Serving % Daily Value*
Potassium Magnesium Aspartate 500mg
Magnesium (as magnesium aspartate) 50mg 12%
Potassium (as potassium aspartate) 70mg 2%
OKG (Ornithine alpha-ketoglutarate) 480mg
Enzyme Enhancement System™ (EES - A proprietary blend of protease and amylase 20mg
* The Percent Daily Values are based on a 2,000 calorie diet. Your daily values may be higher or lower depending on your calorie needs.
† Daily Value not established.
Other Ingredients: Stabilized Rice Bran, Beet Juice, Vegetable Capsules (plant cellulose and water)

Fueling & Usage Tips

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Race PR Kit - AES vol 8.14

The ultimate performance-enhancing trio for race days!

Epic Sessions - Supplement suggestions for workouts and races

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The supplements suggested for use prior to an epic workout or race can be thought of as a preemptive strike...

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Product Reviews

Rated 5 out of 5 by from PR I used Energy Surge and Anti Fatigue Caps for the first time in a race. Couldn't believe the amount of energy I had at the starting line. I ended up running my fastest mile ever as well as setting a new Personal Record by 16 seconds in the 5K.
Date published: 2014-10-29
Rated 5 out of 5 by from Pleasantly surprised about how good these are ! So I read the reviews and thought I'd give them a try - after all, Hammer products have never let me down so far.... and again, they didn't let me down. Having not run heavily in the last few years, I started running again, and to my pleasant surprise, when taking a couple of anti-fatigue caps in conjunction with a couple of endurolytes (which I also recommend) all washed down with lemon/lime HEED I found that I could run longer, faster and recover quicker - without the DOMS issues that I used to suffer from. Have just ordered some more. I am a convert !
Date published: 2015-02-23
Rated 5 out of 5 by from These ABSOLUTELY work with one caveat: These ABSOLUTELY work with one caveat: My personal experience is that AF caps work surprisingly well, unless you use them all of the time. It seems that with constant use (like daily rides), I either develop a tolerance or they just lose their "shine". BUT, when used only on those "special" or "gotta-go-hard-days" they are impressive. Constant use = "dull" or ineffective Occasional Use on Race Day Efforts = may impress you more YMMV
Date published: 2015-07-11
Rated 5 out of 5 by from Don't be Left in the Dark! I have been an endurance athlete for 6+ years and have just recently tried Anti-Fatigue Caps + Race Caps Supreme. I can't believe it has taken me this long to give one of the most effective performance enhancing products a try!! I was blown away by the difference this supplement combination made to my workout and overall energy within a high volume block of running workouts. If there is one combination to pen into your expense budget, it is Anti-Fatigue Caps + Race Caps Supreme!
Date published: 2014-03-13
Rated 5 out of 5 by from Staple Product! Anti Fatigue Caps are an absolute essential Hammer product. Combined with Race Caps, I rely heavily upon these two products for maximum performance!
Date published: 2014-01-04
Rated 5 out of 5 by from Great product! Anti-Fatigue really works! These capsules really help you stay strong till the end. They greatly reduce cramping and when paired with the Endurolytes, WOW! Performance all your competitors will envy.
Date published: 2015-06-15
Rated 5 out of 5 by from So far so good I've only used these with Endurance Aminos in two events so far so I won't say anything with any authority, but...I used them in a 3 hour marathon canoe race that I've done two previous years where I was a hurting unit at 2 hours, and this year I felt great. Could be my conditioning, but I tried the AF caps and they seemed to work. I also used them in a half century, and they definitely worked. I had no cramps or fatigue at any point. So far so good. Will be incorporating these little nugs of gold into my training as well.
Date published: 2014-07-04
Rated 5 out of 5 by from These work I use these before a long run or hard work out. I have felt a difference in my energy, and I seem to be able to work out harder when I take them. In fact, I have started giving them to my husband before his work outs and high school aged kids before they ski and run and they all notice a difference too. Great product to help you get through a tough workout with energy.
Date published: 2015-11-22
  • 2015-11-25T06:40CST
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