Biological Chemicals
... deliver oxygen to the working muscles and helps you to stay cool. As you lose water through sweat, you become dehydrated, decreasing the volume of blood circulating in your body and forcing your heart to pump harder during exercise. Because you now have less fluid in the body, there is decreased sweat production, causing heat to build up in the body. If you don’t take in enough fluids you are running the risk of fatigue, headaches and cramping. Obviously your performance wont be as good as it should if this happens to you. Task 3 vi) Glycosidic bonds are common in plant and animal tissues. A lot of glycosides are known. Some are very poisonous. Others, such as polysaccharides found in our cells, are not. A glycosidic bond is a type of covalent chemical bond that joins two simple sugars via an oxygen atom. The bond may be either above the plane of the ring as in a beta glycosidic bond or below the plane as in an alpha glycosidic link. Below are some examples of glycosidic bonds iv) Endurance athletes, e.g. marathon runners, rely on their stores of glycogen as a source of energy during competition. Carbohydrate loading is a legal method of boosting the amount of glycogen in the body prior to a competition. What is the process? Six days prior to a competition the process begins. · For the first three days the athlete consumes minimal carbohydrate and exercises so as to deplete the bodies glycogen stores. · In the last three days the athlete consumes primarily carbohydrate and reduces the training load. So what just does this process do? At the end of day three the body will think that there is a problem with its glycogen stores and that it should store more glycogen than normal. In the last three days, when the athlete consumes carbohydrate, the body will replenish the glycogen stores and hopefully top them up with a little bit extra. Some possible side effects are: · Muscle stiffness · Diarrhoea · Chest Pain · Depression · Lethargy vii) Drinking fluids during exercise is the best way to prevent dehydration and maintain physiological function. Most of us however, finish exercise at least slightly dehydrated. Isotonic drinks are specially formulated to replace fluids quickly and increase the proportion of ingested fluid, which is retained. Research studies have shown that the fluid in isotonic carbohydrate electrolyte drinks like Lucozade Sport is absorbed as quickly into the body as water. It is recognised that appropriately formulated carbohydrate electrolyte drinks provide the fastest possible fluid replacement. Drinks with a carbohydrate level above 6-8% e.g. fruit juice and some soft drinks, are not recommended during exercise for fluid replacement because as the percentage of carbohydrate goes up fluid absorption is slowed. Isotonic drinks increase the proportion of ingested fluid, which is retained. Drinking plain water causes a rapid fall in plasma osmolality and reduces the drive to drink even before sufficient fluid has been consumed to replace losses. The addition of electrolytes, especially sodium and potassium, to a drink reduces urine output in the post exercise period and is effective in increasing the fraction of the ingested fluid that is retained whereas plain water, caffeinated beverages and alcoholic beverages cause fluid loss by turning on urine production. In this way isotonic carbohydrate electrolyte drinks are effective in increasing the fraction of the ingested fluid that is retained thus promoting rehydration more effectively than water. There are not just energy drinks, which athletes can take now though that is perfectly legal, there are also energy bars. The newest energy bar on the market is the Boost Guarana. Cadbury have launched a challenge to energy drinks companies with Britain’s first stimulant chocolate bar. The new Cadbury’s bar, Boost Guarana is intended to stimulate mental energy by increasing attention span and alertness. It claims to new bar matches and in some cases, outperforms energy drinks. Leading brands in the field include Red Bull and Lucozade. Guarana is a South American plant extract known to native Indians for centuries. It’s a berry that grows specifically in Venezuela and northern Brazil whose seeds contain guaranine, which has a similar stimulant effect to caffeine. Isotonic sports drinks - Lucozade Sport etc. - provide fluid, energy and electrolyte replenishment. These components are depleted during exercise due primarily to an increased perspiration level - we sweat these elements out. Of course fluid (water) replacement is important - if water isn't replaced in our exercising system we rapidly dehydrate and in extreme cases exercise must cease completely. In more normal cases exercise performance dips far below an optimal level. Electrolytes are essentially salts lost in sweat. Replacing them will aid the digestion and osmosis of fluid absorbed into body's working muscles - without them the fluid within the drink will not be fully absorbed and the effects of dehydration will still soon rear their ugly head. Energy within isotonic drinks comes in the form of glucose. Working muscles use this as fuel during exercise training. Replenishing them during training will allow you to train longer than if you just took plain water on board. Drinking an isotonic sports drink directly after exercise will allow the body's recovery rate to improve, as glycogen re-synthesis will start ASAP. Sports drinks should be taken approximately an hour before sport for maximum effect. Task 4 – Lipids viii) ‘Endurance training affects a person’s ability to utilise fats’. I agree with the given statement because activities of many muscle enzymes responsible for the beta-oxidation of lipids increase with endurance training. This adaptation is essential to allowing endurance-trained muscle to burn lipids more efficiently, in turn reducing the demand placed on a muscle’s glycogen supply. Aerobic training also increases the rate at which free fatty acids are released from storage during prolonged exercise. This elevation of FFA enables muscle to burn more fat and fewer carbohydrates. Endurance trained muscles capacity to use fat is caused by the enhanced ability to mobilize FFA and the improved capacity to oxidize fat. Task 5 ix) Polypeptides and proteins are held together by amide bonds between the amino-end on one amino acid molecule, and the carboxylate-end of another amino acid molecule. In a peptide, this amide bond is called a peptide bond. Peptide bonds are quite strong and fairly rigid - amides have a resonance structure in which there is a double bond between the amide nitrogen and the carbonyl carbon. This resonance structure is very important to understanding the behaviour of peptide bonds - they are rigid and flat. In addition, an important property of peptide bonds is their ability to form hydrogen bonds. These hydrogen bonds are crucial for the formation of secondary structure in proteins, such as the alpha helix and the beta sheet. This involves the hydrogen on N (which has a significant partial positive charge due to resonance) forming a "bond" with a lone pair from nearby carbonyl oxygen. The formation of a peptide bond between two amino acids is an example of a condensation reaction. Two molecules are joined together with the accompanying removal of a molecule of water. A diagram showing this is below; - x) How does protein influence the role of the sport and exercise? Only a few amino acids can be used by muscles for energy and their oxidation accounts for only 2-5% of the total energy, even during intense exercise. Most of the energy for exercise comes from carbohydrate and fat. The best scientific studies have been unable to show that branched-chain amino acid ingestion during exercise benefits performance. In fact, a potential side effect of amino acid ingestion during exercise is excess ammonia accumulation (a by-product of amino acid breakdown), which could contribute to fatigue. It has been suggested that consuming a protein-carbohydrate mixture during exercise will raise blood insulin to higher levels than carbohydrate alone, increasing the use of carbohydrate in muscle to better delay fatigue. Although there are a few published abstracts that point to such a conclusion, these studies have yet to be published in a peer-reviewed scientific journal, so it is impossible to determine the validity of the results. At this point, we can only conclude on the basis of published research that ingesting amino acids (and likely protein) during exercise has no effect on exercise performance. Although future publications may provide a different perspective, it is hard to imagine how ingesting small quantities of protein or amino acids during exercise could benefit performance. For example, if higher blood insulin levels did result from ingesting a protein-carbohydrate drink during exercise, this could possibly reduce fat oxidation and fatty-acid availability. Well-trained athletes have an incredible ability to use fat as a fuel. In fact, this helps them save carbohydrate for when it’s needed the most; for example, during a finishing sprint. Along these lines, there are no good scientific data to show that ingesting protein along with carbohydrate during exercise spares the use of muscle glycogen or increases the uptake and use of blood glucose by muscle. Athletes are always searching for a competitive edge and often look to a supplement or special combination of nutrients to find it. Research has shown, however, that there are no magic-bullet supplements for improving sports performance and, while a cornerstone nutrient for the athletic diet. Protein plays an important role in helping the body recover from training and competition and a balanced nutrition shake or bar may be an effective way to jump-start this process. Enzymes At any given moment, all of the work being done inside any cell is being done by enzymes. If you understand enzymes, you understand cells. A bacterium like E. coli has about 1,000 different types of enzymes floating around in the cytoplasm at any given time. A protein is any chain of amino acids. An amino acid is a small molecule that acts as the building block of any protein. If you ignore the fat, your body is about 20-percent protein by weight. It is about 60-percent water. Most of the rest of your body is composed of minerals (for example, calcium in your bones). Enzymes have extremely interesting properties that make them little chemical-reaction machines. The purpose of an enzyme in a cell is to allow the cell to carry out chemical reactions very quickly. These reactions allow the cell to build things or take things apart as needed. This is how a cell grows and reproduces. At the most basic level, a cell is really a little bag full of chemical reactions that are made possible by enzymes! Enzymes have extremely interesting properties that make them little chemical-reaction machines. The purpose of an enzyme in a cell is to allow the cell to carry out chemical reactions very quickly. These reactions allow the cell to build things or take things apart as needed. This is how a...