Today, my usual daily bicycle ride to maintain my cardiovascular fitness and leg strength for my school-year sport of crew, my normal routine was interrupted to a large degree (to use euphemistic terms). During one of my high-speed intervals on one of the many bicycle/pedestrian paths around my house, I saw about 100 feet in front of me an older woman with an accompanying Beagle. As I approached the couple, the woman began to draw the dog towards her, apparently preparing to let me by, but within five feet, she let her dog go, prompting me to swerve off of the path.
This is where things get interesting. My eyes see my front wheel canted, trying to regain their grip on the pavement, but sliding in the post-rainstorm moisture. The eyes also are tuned into the odd slanted orientation of the horizon – a major roll and position cue in the brain. The fluid in the Superior Semicircular Canals of both my ears registers to my brain that I am severely off balance, slowly falling to the left. All of these signals are routed to the “emergency call center” of my brain – the Amygdala. Recognizing the immense danger my body is now subjected to and trying to initiate the “damage control protocols,” my Amygdala sends the “Fight or Flight” signal that we all are so used to hearing about to my Hypothalamus. The Hypothalamus is the “fire station” to the Amygdala’s “911 switchboard,” and routs the Fight or Flight message to my Adrenal Glands (which are directly above my kidneys). I would like you, my reader, to consider now the incredible speed with which this signal is routed… By the time my Adrenal Glands have received the signal to function, it has been less than a second!
My flustered Adrenal Glands have now begun to produce the Catecholamines Epinephrine (medical for Adrenaline) and Cortisol. Both of these hormones are “stress hormones” and play specific roles in our bodies. Cortisol deals with extended stress (like work) and counteracts insulin to supply you with increased blood sugar in situations where you might need it, and has an auxiliary use in the brain, where it stimulates the Hippocampus (the memory center) to make “higher definition” or more pronounced memories of the incident. Adrenaline is that instant energy boost you get when you are “flustered,” and increases heart rate drastically and stimulates the release of glucosamine in your muscles – the fastest and most powerful energy source your muscles have.
I have just hit the cold, hard, wet pavement. The Utricle (basically a human accelerometer) in my inner ear slams forward and informs my brain that, indeed, a collision has occurred. My hip hits first – a powerful impact injury along with the bite of gravel that scrapes skin away. Then my center of gravity shifts toward my torso and I slide for nearly ten feet on the top of my shoulder before coming to a stop on the ground. My bout with gravity has been settled and I have lost. It’s time to take inventory and go home.
I stand up. I feel no pain. The woman asks me if I am okay, if I need a ride home. I respond simply, “yeah, no I’m fine.” The Adrenaline and Cortisol coursing through my veins imbue me with incredible strength, but this is not the important physiological event in my body – Episodic Analgesia (a lack of pain) has been activated in my brain. My brain has “stopped” interpreting pain signals; it has determined pain is of no importance right now, that survival of the organism (yours truly), is of the utmost urgency. So I quickly and calmly reach into my First Aid Kit and pull out several alcohol wipes to clean my wounds, and I am surprised when I feel only the touch on my skin, and no pain whatsoever, no sting, no caustic burn of the alcohol.
My front tire wobbling, I ride home quickly and hang my bike up before heading straight to the shower. The pain is quickly setting in and I am breathing shallowly and shaking – the pain has stimulated the release of more adrenaline. My wounds are bleeding, but due to another miracle of the human body, are closing up – the body’s temporary solution to the bleeding, Platelets (think of them as little gobs of glue in the bloodstream), are sticking blood cells together to stop the flow of blood and close up the pressurized system that has been ruptured.
After my shower, the systems on alert in my body have calmed down and I am stinging all over my right side. The wounds are weeping and I take Acetaminophen to dull the pain, sit down at my computer to write this post, and wait for my wounds to dry and scab over.
Considering the fifteen mile-an-hour crash my body had taken, falling five feet and sliding ten, I would say that my body’s defenses have more than risen to the challenge. I sustained two six-by-two inch abrasions and one long scratch on my forearm, and am still recovering, but I feel great! The ingenious design of my body has ensured my survival to another day… and I expect it to be be tested many times more.