The hypothesis was mostly supported by the data; however, there were a few unexpected data points where the heart rate was higher before the person exercised, or the heart rate stayed the same after exercising. The same goes for breathing where the respiratory rate was higher before the exercise or stayed the same after exercising. Most of the time the heart rate and respiratory rate increased after exercise because of the negative feedback loops trying to maintain homeostasis in the body. Homeostasis is how the body attempts to make an equal balance in itself so that the human can survive; such as the processes of cellular respiration and negative feedback loops. Cellular respiration helps maintain homeostasis by making oxygen and letting out carbon dioxide. Two negative feedback loops occur because of exercise. Negative feedback loops help maintain homeostasis. These negative feedback loops happen at the same time. The first negative feedback loop starts with exercising which increases CO2 in muscles and decreases oxygen traveling around. The CO2 is acidic and it lowers the pH of the blood. Since the pH of the blood is lowered, nerve receptors pick up on it and a message for the diaphragm and muscles to start contracting faster gets sent to the lower brain stem. After the contracting gets faster there is decreased CO2 in the blood and more CO2 is exhaled out of the body to maintain homeostasis. Then, pH levels in the blood and oxygen levels in the muscles start to rise. The second negative feedback loop is when exercise starts to make the brain get excited and the brain sends a signal to the adrenal glands to release epinephrine. The epinephrine is adrenaline and it increases the heart rate in the body which leads the person to breathe in more air and allows blood to flow faster to the muscles. More air being breathed in and blood flowing faster to the muscles is also an attempt by the body to maintain homeostasis.