Concepts Of Lifetime Fitness :: essays research papers

Concepts of Lifetime FitnessHomeostasis is the state of equilibrium in which the national environment of thehuman body stay relatively constant. Two tenuous examples of homeostasis ar how the body maintains a constant temperature and blood pressure during heavy physical activity or exercise. Although there are many separateactivities in the body that display homeostasis, I will only reason these two. Temperature in the human body is usually kept at or so 37 degreesCelsius. To maintain such a strict temperature, the body has a few functions tocombat the outside elements. People cannot make themselves cold as readily asmake themselves hot, however I will pay heed both homeostasis functions. Whenthe external temperature decreases, a portion of the intelligence called thehypothalamus detects the drop by means of the blood. To compensate, the brainsends chemical and electrical impulses to the muscles. These impulses tell themuscles to begin to father and relax at very high inte rvals. This is commonlyknown as shivering. The production of Adenosine Triphosphate or ATP in themitochondria of the muscles produces passionateness. If the body temperature does not stand immediately after this, then a second function begins. The brain willsignal the blood vessels near the skin to constrict or narrow in diameter. Thisoccurs so the heat deep in the muscles is conserved. Since the vessels are nowsmaller in diameter, less blood is geted to claim them. Since less blood isneeded through the vessels, the heart begins to slow. If the body remains inthis slowed state, hypothermia could result. Hypothermia is the condition inwhich metabolic processes are inhibited. The medical mankind has taken advantageof this by inducing hypothermia in patients that are undergoing organtransplants.To fight temperatures higher than normal, as in exercise or on hot days, thebody reacts in the opposite way than with cold. Again, the hypothalamus detectsthe change of temperature in the b lood. The brain signals blood vessels not toconstrict, but to dilate. This increases the diameter of the vessels, andresults in the need for more blood. Since more blood is needed to fill thevessels, the heart pumps fleet and that causes respiration to increase. Theincreased respiration will make the body pass some of the internal heat, likeplacing a fan in a window to cool a room. The blood vessels are dilated so theheat deep in the muscles is easily released. Another commonly known chemical mechanismto fight heat is sweating. Sweat glands found throughout the body arestimulated by the hypothalamus to excrete sweat and when the sweat evaporates,