Diego's "Yes! Yes! Yes!" battle chant. Guida's pre-fight leaping and face slapping. The fighters staring into the distance, bobbing their heads to music only they can hear. Regardless of the preferred technique, they are all seeking the same thing. They are in search of the Superhuman.

The reality of superhuman feats of strength and endurance in combat has been known since the age of the Norse hero, Berserk. Originally identified in mammals as the fight or flight response, virtually all higher animals possess a neurologic trigger to maximize their ability to survive mortal danger.

In humans the response is modulated by the Sympathetic Nervous System (SNS), a branch of the autonomic nervous system that regulates the body's equilibrium. In an emergency, structures deep within the brain trigger the alarm; electrochemical signals are then fired through a chain of sympathetic neurons to the adrenal gland and other critical organs. The plenipotent adrenal gland pumps adrenaline and cortisol into the bloodstream -- in moments, arteries deliver the drugs to every cell in the body. Within fractions of a second the body is primed for maximal exertion.

There are numerous well-documented, quantifiable instances of the physical feats possible under maximal sympathetic stimulation. In 2006 a passerby named Tom Boyle Jr. saw a Camaro pin to the ground a young cyclist. In front of a dozen witnesses, Boyle rushed to the scene and lifted the car, allowing the cyclist to be pulled free. Factoring in leverage, Boyle dead lifted, without warm-up or equipment, close to 1,500 pounds: the Olympic record is less than two-thirds that.

In 1991 at the Track and Field World Championships, Mike Powell added an unheard of 30 centimeters to his previous best to set the long jump world record with a jump of 8.95 meters. It was a unique performance, triggered by ideal mind and body conditions: Powell never had a jump anywhere near 8.95 again.

And then there are examples less quantifiable but perhaps more amazing: In 2002 a slight Eskimo woman, Lydia Angiyou, attacked a polar bear menacing her child. She fought off the animal for several minutes before it was dispatched with a rifle.


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A fighter standing in the ring at full sympathetic arousal is an awesome physiologic specimen. Adrenaline pre-tensions the muscles, as taut muscle contracts with greater force than slack, causing the body to tremble in anticipation. The blood vessels feeding those muscles dilate, increasing the flow of oxygen and nutrients. Conversely, capillary beds in the skin shut down, making the skin cool and pale. This serves to shunt more blood to the muscles and lessens bleeding from anticipated wounds. The gut, a large drain of resources during the baseline "feed and breed" state, is shut down. A fighter has “butterflies,” nausea and over a long duration, necrotic bowel mucosa.

The heart accelerates and contracts with greater force -- often you can see a fighter's chest shaking with the force of each heartbeat. The lowered vascular resistance increases cardiac stroke volume even further; in milliseconds, cardiac output can leap from an unremarkable 5 liters per minute to more than 20 liters per minute. The bronchioles dilate, decreasing resistance in the lungs, and the fighter's respiratory rate increases. This increases oxygen intake and facilitates expulsion of the carbon dioxide that is the byproduct of muscle metabolism.

To feed the muscles, stores of glycogen are broken down into glucose, and fat stores are broken into consumable fatty acids. The pupils dilate, the mouth goes dry. Sweat covers the fighter, dissipating the heat of muscle exertion and making him more slippery in a predator's grasp.

The most fascinating preparations for battle occur in the brain itself. Concentration is heightened and focused. Endorphins and endocannabinoids are released to blunt the coming pain. The higher-level cognitive processes of judgment and planning are bypassed, or at least de-prioritized, and reflex and instinct are raised to prominence. The sometimes crass behavior of fighters suddenly victorious after a flash knockout should be no surprise -- they are high on powerful drugs.

In toto, an organism ideally designed for the work of thought, nutrition and reproduction has been transformed into a killing machine.



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For athletes, quantification of the extent to which effective triggering of the SNS can improve performance has perhaps best been achieved by Vladimir Zatsiorsky in his book, “Science And Practice of Strength Training, Kinetics of Human Motion.” Zatsiorsky posits that an average athlete can utilize at best 65 percent of his maximum potential strength. Through training and practice an elite athlete can capture as much as 20 percent more of that potential. The keys to unlocking the ultimate 15 percent lie beyond the conscious mind: The fighter who taps into that reservoir of power most effectively has given himself a crucial advantage.

There is of course a downside of the tremendous power unleashed by the SNS. Researchers describe the performance to stimulation relationship as “inverted U" shaped: Once optimization is achieved, further stimulation results in decreased performance. A little fear is exciting, a little more elicits a fortifying flood of neurochemicals and a little more renders an individual paralyzed and incapacitated. Some fighters rise to the occasion and some fighters choke at the moment of greatest pressure. Part of the mental art of fighting lies in consciously initiating the SNS and then preventing the fight or flight response from revving out of control. The fighters capable of that seem to have dynamite in their fists and ice in their veins.

That level of control over the autonomic nervous system requires hard won mental discipline. An easier path to triggering the SNS is to simply use chemical stimulants. Caffeine provides some competitive edge below 12 micrograms/ml: At these levels, just more than a Venti Starbucks coffee, studies show athletic endurance increases -- possibly by as much as 50 percent. Over-the-counter Sudafed, pseudoephedrine, is a cheap source of chemical stimulation. Cocaine and amphetamines are exceptionally potent stimulants. Even marijuana, clearly not a stimulant, may provide a competitive edge by mimicking the role of endocannabinoids in the brain.

When people wonder what keeps athletes in a sport where pain and injury are unavoidable, the answer may lie in the tremendous SNS stimulation it provides. Few human activities, and no other sport, can match the incredible stimulation an animal experiences by stepping into the ring with a known predator. Within seconds after the fight the SNS shuts down, adrenaline degrades and the fighting high is replaced by an emotional and physical crash. The only hope of recapturing that intense power, focus, thrill -- of once again being superhuman -- is to fight again.

Matt Pitt is a physician with degrees in biophysics and medicine. He is board-certified in emergency medicine and has post-graduate training in head injuries and multi-system trauma. To ask a question that could be answered in a future article, e-mail him at mpitt@sherdog.com.