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Cellular Respiration

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Does Lactic Acid Build Up Cause Muscle Burn? Have you ever felt a burning sensation in your muscles after an intense sprint, or maybe peddling up a hill on a bicycle? The common belief is that this burning sensation is caused by lactic acid build up in our muscles, which eventually forces us to stop exercising. But does lactic acid really cause muscle burn? The answer is a resounding “No”, it doesn’t.

In fact, lactic acid build up helps reduce the burn. While this article is a bit technical, it will help you understand the true dynamics of why you feel muscle burn during exercise and what lactic acid really is. How Lactic Acid Build Up Works Your body needs energy to function and glucose is its primary fuel source during exercise. So, during times when there is not enough oxygen, such as when you are exercising intensely, the cell cannot keep up production of ATP to meet its energy demands, leading to increased glucose break down into pyruvate, Now the pyruvate, instead of going through the Krebs cycle, is converted to lactate.

Creatine Supplementation in Athletes: Review. By Mark A. Jenkins, MD If you haven't yet heard of creatine supplementation you soon will. It is being promoted as a muscular performance enhancer, and there is scientific evidence to support this. Unfortunately, claims have escalated beyond science, and now athletes from a wide variety of sports have begun taking this substance. The pursuit of performance enhancing potions has historically been like the alchemists dreams turning lead into gold. Physiology of creatine in exercise The key to understanding creatine supplementation is to appreciate that it only helps with certain activities. Diagram 2 illustrates the energy pathwys that are the most important for all-out exercise of differing times. Diagram 2 Aerobic endurance athletes, such as distance runners and triathletes, represent a much different picture from power athletes.

Thus, "slow twitch" athletes cannot generate the speed and force of their "fast twitch" cousins, but they can do their thing for a long time. Cited References. CHAPTER 3: CALCULATION OF THE ENERGY CONTENT OF FOODS - ENERGY CONVERSION FACTORS. As stated in Chapter 1, the translation of human energy requirements into recommended intakes of food and the assessment of how well the available food supplies or diets of populations (or even of individuals) satisfy these requirements require knowledge of the amounts of available energy in individual foods. Determining the energy content of foods depends on the following: 1) the components of food that provide energy (protein, fat, carbohydrate, alcohol, polyols, organic acids and novel compounds) should be determined by appropriate analytical methods; 2) the quantity of each individual component must be converted to food energy using a generally accepted factor that expresses the amount of available energy per unit of weight; and 3) the food energies of all components must be added together to represent the nutritional energy value of the food for humans.

The unit of energy in the International System of Units (SI)[8] is the joule (J). 3.5.1 The Atwater general factor system. Glycolysis: Process of Glucose Utilization and Homeostasis. Return to The Medical Biochemistry Page © 1996–2014 themedicalbiochemistrypage.org, LLC | info @ themedicalbiochemistrypage.org Dietary carbohydrate from which humans gain energy enter the body in complex forms, such as disaccharides and the polymers starch (amylose and amylopectin) and glycogen.

The polymer cellulose is also consumed but not digested. The first step in the metabolism of digestible carbohydrate is the conversion of the higher polymers to simpler, soluble forms that can be transported across the intestinal wall and delivered to the tissues. The breakdown of polymeric sugars begins in the mouth. The main polymeric-carbohydrate digesting enzyme of the small intestine is α-amylase.

Oxidation of glucose is known as glycolysis.Glucose is oxidized to either lactate or pyruvate. Back to the top Aerobic glycolysis of glucose to pyruvate, requires two equivalents of ATP to activate the process, with the subsequent production of four equivalents of ATP and two equivalents of NADH. Muscle Soreness. Written by Daryl At least one time or another, all of us have experienced muscular soreness, particularly with weight-trianing programs. Generally, two types of muscle soreness are recognized. (1), Acute soreness, and (2) delayed soreness.

Acute Soreness The reasons for Acute Soreness. 1. Muscular pain is produced during contraction in which the tension generated is great enough to occlude the blood flow to the active muscles (ischemia). 2. 3. Delayed Muscle Soreness Acute soreness, although often an annoyance, does not pose much of a problem because it is short-lived (acute) and is alleviated when exercise is discontinued. From experiments designed to induce delayed muscular soreness, it has been found that the degree of soreness is related to the type of muscle contractions performed. 1. 2. 3. Studies designed specifically to investigate these theories concluded that delayed muscular soreness is most likely related to disruption of the connective tissue elements in the muscle and tendons. Science of the Olympic Winter Games. Cellular Respiration.