Endurance and Fight or Flight

Endurance training today for four hours and I have to talk about the dog owners around. Part of an endurance runner you have planned how to fuel and hydrate for the amount of calories you are using. I am a dog lover for sure but your little FiFi should be on a leash or behind a fence. That is the law after all. When I go out for a four hour run and know I have the rough winds to run against let me tell you what happens to my sympathetic nervous system when FiFi is biting at my ankles and you can’t run to catch her but your reassuring me that she is a sweet dog. Your sweet dog just waisted unnecessary energy from me. My heart rate rises which causes my fight or flight system to take over. The sympathetic nervous system uses nerve pathways to initiate reactions in the body, and the adrenal-cortical system uses the bloodstream. The combined effects of these two systems are the fight-or-flight response. When the hypothalamus tells the sympathetic nervous system to kick into gear, the overall effect is that the body speeds up, tenses up and becomes generally very alert. The combined effects of these two systems are the fight-or-flight response.The sympathetic nervous system sends out impulses to glands and smooth muscles and tells the adrenal medulla to release epinephrine (adrenaline) and norepinephrine (noradrenaline) into the bloodstream. These “stress hormones” cause several changes in the body, including an increase in heart rate and blood pressure. The sudden flood of epinephrine, norepinephrine and dozens of other hormones causes changes in the body that include:
heart rate and blood pressure increase
pupils dilate to take in as much light as possible
veins in skin constrict to send more blood to major muscle groups (responsible for the “chill” sometimes associated with fear — less blood in the skin to keep it warm)
blood-glucose level increases
muscles tense up, energized by adrenaline and glucose (responsible for goose bumps — when tiny muscles attached to each hair on surface of skin tense up, the hairs are forced upright, pulling skin with them)
smooth muscle relaxes in order to allow more oxygen into the lungs
nonessential systems (like digestion and immune system) shut down to allow more energy for emergency functions
trouble focusing on small tasks (brain is directed to focus only on big picture in order to determine where threat is coming from)
So please from all the runners I know…….keep FiFi away from me either leashed, chained or fenced! I now carry pepper spray and use it liberally. I truly appreciate your help on this!

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