8/31/12

Stimulate Yourself


This topic is one that will be up for debate within the fitness community so bear with me as this is my opinion.  Let's say your low on sleep, running a hundred mph and trying to keep a fit and healthy lifestyle. The first thing to address is that not sleeping and thinking you'll  be healthy is pretty ridiculous, but i know that some of us have no choice. You may be getting plenty of sleep but are constantly having heavy lifting day's or very intense workouts [crossfit/EnduWod]. The body is made to handle a stress response but only to a certain extent. Once stress is past the point of being anywhere near homeostatic, a state of normality or proper function, we see injury. For example our bones have a level of homeostasis that we never think about.

When we run or do athletic movements the bones take force and are damaged/stressed; we have an intricate system of bone builders and breakers fixing the damaged bone and creating new, strong bone. Without a stress the bone does not have a response to rebuild more densely; similar to exercise and the body, without stress the body stops working hard to function "athletically." With too much stress the bone breaks and we have a screaming in pain situation.

Bones are not today's topic though, we're talking about the Central Nervous System [CNS] and it's response to fatigue. First and foremost some people consider CNS fatigue a theory, and that the fatigue is more peripheral. Some even believe that CNS fatigue doesn't exist. I believe that fatigue can occur anywhere between the CNS and the myofibrillar level. One theory on CNS fatigue is that it is a response to keep the body from harm when the muscles [myofibrillar] are fatigued. [1] That makes complete sense to me on a survivalist stand point. Seeing as how we don't sleep like a survivalist, who could easily get 8-10 hours a day, we may be receiving a CNS fatigue response that isn't necessary.

A study conducted that supports this idea was done on cyclists who were forced to ride at max effort for as long as possible. When fatigue was being reached the neurons were actually having inhibitory responses towards the CNS. [2] The conclusion states that the CNS was functioning to protect the organism from over exerting at the moment. This usually occurs in either a very hot environment or when the cells are oxygen deficient [hypoxic]. Once again though if you're competing or trying to do superhuman feats in the name of fitness this slows down our progress. We don't have to run from a lion later unlike our ancestors might have had too. We can exhaust our self now and not worry about survival later.

Okay ath-uh-leets this is the important part linking to the data above. When we're trying to do things that are super human, and our bodies are getting in the way we have to get the body to catch up. Stimulate Yourself. The first thing to compensate this fatigue is carbohydrates [3]. Research has shown that carbohydrates can delay overall fatigue along with CNS fatigue. We know the brain runs on fats and carbohydrates so there is no point to neglect either or if you're a high level athlete. Caffeine is a two edged sword. Depending on who you are caffeine has been shown to either stimulate and amp the CNS or delay and inhibit it.[4,5] My advice, and I'm not a doctor so this is not prescription, is to test how you respond to different levels of caffeine. For me I know that 200 mg of caffeine stimulates me, however anything that is near 300 mg seems to slow me down. NEVER test your caffeine levels on a competition day, that's suicidal. Another thing to try is BCAA's [6]. Some studies have found that when combing Branch Chained Amino Acids with carbohydrates overall fatigue and mental degradation decreased. In other words people were less tired and thought faster when taking these in conjunction.



A rule of thumb to live by is that we are all the same type of organism, we all share tons of DNA code, but we still all have our very own set of information. I'm not you, and you're not me. You may not need a CNS stim, it may be exactly what your looking for. Test it for yourself.

In conclusion I find that a good preworkout may be necessary for improved performance and a more enjoyable workout. I know that waking up at 6 to go do EnduWod is much more enjoyable and I can go harder when I have taken a Stimulating, carbohydrate based preworkout.



  1. Noakes TD. (2012) Fatigue is a Brain-Derived Emotion that Regulates the Exercise Behavior to Ensure the Protection of Whole Body Homeostasis. Retrieved (2012;3:82. Epub)
  2. Amann M. (Nov 2011) Central and peripheral fatigue: interaction during cycling exercise in humans. Retrieved (pubmed  43(11):2039-45.)
  3. Davis JM. Alderson NL, Welsh RS. Serotonin and central nervous system fatigue: nutritional considerations. American Journal of Clinical Nutrition. 2000 August; 72(2 Suppl): 573S-8S
  4. Graham TE. Caffeine and exercise: metabolism, endurance and performance. Sports Medicine. 2001;31(11):785-807
  5. Kalmar JM, Cafarelli E. Central fatigue and transcranial magnetic stimulation: effect of caffeine and the confound of peripheral transmission failure. Journal of Neuroscience Methods. 2004 September 30;138(1-2):15-26.
  6. Newsholme EA, Blomstrand E. Tryptophan, 5-hydroxytryptamine and a possible explanation for central fatigue. Advances in Experimental Medical Biology. 1995;384:315-20

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About Me

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BS, MS - exercise Physiology
EPC - Board Certified Exercise Physiologist

Published Thesis
The impact of three different forms of warm up on performance


The Effects of Glucose Supplementation on Barbell Velocity and Fatiguability in Weightlifting - A pilot study"

Graduate from Midwestern State University, founder of Endunamoo Barbell Club, and Endunamoo Strength and Conditioning. Working to help athletes physically reach their goals and achieve scholarships while spiritually pouring into as many people as possible on all platforms.