The goal of this scientific study was to determine if the delayed onset of fatigue, as a result of consuming carbohydrates, was associated with stopping muscle glycogen depletion. Therefore, this web page is dedicated to presenting the important points of the study and to expand on those ideas in order to encompass a more general function of carbohydrates in our daily activities.
The basic outline of the experiment consisted of a control group and an experimental group; both groups contained endurance-trained cyclists who had fasted beforehand. The cyclists were required to maintain a constant 70% aerobic workload while they cycled. The control group was given a sweet drink that did not suffice as an energy source; the drink contained aspartame (NutraSweet) which has no nutritional value. The other drink contained nutritionally useful carbohydrate that had an equally sweet flavor. Cyclists were not told which drink they were receiving. This was done to avoid biases (such as cycling harder with the carbohydrate drink to "please" the scientists) from entering the experiment and thus corrupting the data.
Muscle biopsies to measure muscle glycogen were taken before excercise, after 2 and 3 hours of exercise, and at the time of fatigue (when the cyclists could no longer work at 70% of their aerobic capacity). Blood samples were also taken every twenty minutes and upon fatigue. These blood samples were used to quantitatively analyze the glucose levels in the blood at the various times.
The results of this study were that carbohydrate feedings during prolonged exercise delayed fatigue by one hour. As seen by the results of the carbohydrate feeding during the bicyclists' extensive exercise, glycogen utilization is not spared in ...
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Another clinical study was also done with Carbo-Crunch Bars by Shaklee. Cyclists pedaling at an energetic pace for more than three hours received Carbo-Crunch Bars and water or water alone. The speed was then turned up to sprint pace. Those who had been drinking water and eating the Carbo-Crunch Bars were able to last 24 minutes while those participants who had received only water lasted for an average of 2 minutes.
Results:
These clinical studies of Shaklee products show that carbohydrates help to prolong the onset of fatigue to keep the athlete going. Carbohydrate products have become so popular that dogs can even receive Power Bones, a product offering dogs a burst of energy from glucose and endurance from carbohydrates. The regular intake of carbohydrates during exercise help to keep body-sugar levels steady and prolong the onset of fatigue.
The data collected during this experiment has shown that a relationship likely exists between the rate of muscle fatigue and the time spent performing vigorous exercise prior to the set of repetitive movements. This is likely due to a build-up of lactic acid and lactate as a result of anaerobic respiration occurring to provide energy for the muscle cell’s movement. As the pH of the cell would have been lowered, the enzymes necessary in the reactions would likely not be working in their optimum pH range, slowing the respiration reactions and providing an explanation to why the average number of repetitions decreased as the prior amount of exercise increased.
For this experiment to work correctly, the following controls must be followed: Each subject must have at least 7 hours of sleep the night before the workout session. There is to be one and only one designated exercise per day. This is because if more than one exercise is done per day, the results can get corrupted. The same amount of pre-workout must be consumed by each test subject. (2 scoops of C4 with 12oz of water) The exercises that are performed must be done correctly in order for them to be considered valid. The exercises that are to be done after the pre-workout is consumed should be done around 30 to 35 minutes after. “To take C4 Extreme, simply mix 1-2 scoops of C4 Extreme with water (or juice), 15-30 minutes prior to your workout” (www.cellucor.com) Test subjects should remain hydrated throughout the day to ensure peak perfor...
AERENHOUTS, D., DERIEMAEKER, P., HEBBELINCK, M., & CLARYS, P. (2011). Energy and macronutrient intake in adolescent sprint athletes: A follow-up study. Journal Of Sports Sciences, 29(1), 73-82.
Muscle fatigue is a decline in ability of a muscle to generate force within any part of the body. Muscular fatigue is a particular response when it comes to an untrained athlete that is starting an intense workout program, and the muscles of the body is not able to respond in an orderly manner as it would respond to an elite athlete. This paper will focus and provide general information about recent studies on peripheral fatigue. Peripheral fatigue is one of the sites for possible fatigue and its where neural, mechanical, or energetic events can hamper tension development. Neural fatigue is a factor of peripheral fatigue, which occurs when the nerves are unable to generate a signal and this reduces the ability of the muscle fiber to contract which is considered to be metabolic fatigue. Neural factors deals with the movement of action potential going through a process to produce a muscle contraction and when this process does not go through the proper steps then fatigue set in because the muscles will not be able to contract. Neural fatigue has two main factors which is, a shortage of...
The strict limitation of carbohydrates in a diet may appear to give the desired result of weight loss, but actually brings many health risks. Instead, carbohydrates help to reduce health risks, and also provide your body with key sources of energy. Not only are carbohydrates the main source of energy for the body, but they also create fiber which helps the body’s organs to function properly. The consumption of carbohydrates is important for normal functions of the body, but especially for the performance of an athlete. In order for maximum athletic performance, a large amount of carbohydrates must be consumed throughout the period of a workout. Overall the right amount of carbohydrates and exercise are necessary for a healthy diet.
Philp, A., Burke, L. M., & Baar, K. (2011). Altering endogenous carbohydrate availability to support training adaptations doi: 10.1159/000329279
Miller, SI and Wolfe, RR. "Physical exercise as a modulator of adaptation to low and high carbohydrate and low and high fat intakes." European Journal of Clinical Nutrition. 53:112-9, Apr. 1999
Shi X, Gisolfi CV. Fluid and carbohydrate replacement during intermittent exercise. Sports Med 25 (3): 157-172, 1998.
In 2002, a group of Australian researchers published a paper entitled the "Effect of different protocols of caffeine intake on metabolism and endurance performance". Caffeine use during sporting events has become much more popular and has widely studied. The purpose of the research was to examine the work increasing (ergogenic) effects of differing regiments of caffeine on metabolism and performance while simulating the typical nutritional preparation an athlete would do for a race. The study also sought to examine the effect of timing of caffeine intake, comparing results when caffeine was given before an event (precaf) to results from caffeine given during an event (durcaf). In addition, the researchers wanted to understand the practice of endurance athletes drinking defizzed Coca-Cola towards the end of a race. It was widely observed that many triathletes and marathoners feel they derive a boost from consuming Coca-Cola in the final stages of an event as a replacement to sports drinks.
A randomized, counterbalanced intervention approach increased validity of the data compared to the previous observational study. However, there were only 10 participants who were studied over a short period of time. Increasing the number of participants would be a valid approach to either confirm or negate the most recent findings. In addition, a short-time period is not ideal when studying the body of adults who have had steady eating habits for at least 10 years. Extending the time period over which participants alter their diets would allow more time for adjustments to be made within the body. While the data was determined to be significant, it is hard to tell if one would have similar findings if done over a longer period of time, or if the body would continue to change. Furthermore, testing was not inclusive of the causation of the results; while there are implications of causation seen by the correlation of the studied factors, it is possible that other factors were involved and influenced results. By altering the systemic pH, it is possible that the enzymes responsible for the breakdown of the macronutrients were not able to function at their optimal level. By changing the diet, and therefore the systemic pH, enzymes may not have been able to break down nutrients as efficiently, therefore causing a difference in RER during exercise. However, further research is
Graham, TE. (1998) Effects of Caffeine on Metabolism, Exercise Endurance and Catecholamine Responses and Withdrawl. London
Carb cycling, a diet plan that alters the intake of carbs on a daily basis in order to keep metabolism high without a plateau or muscle loss, is growing in popularity for everyday people, endurance athletes, power lifters, and body competitors. That is not too surprising considering its simplicity and effectiveness. The basis of carb cycling is that from day-to-day one’s diet is constantly changing in the amount of carbohydrates and fats that are consumed. This results in overall fat loss while gaining muscle with more psychological ease, making it one of the easiest diets out there; however, there is no day-by-day instruction manual to follow. It takes knowledge and knowing one’s body. Everyone’s body is different; thus, every diet will be different, but learning how to alter the diet based on one’s body and daily routines is the key. To be more specific, endurance athletes have very different nutrition needs than power lifters, non-endurance sports, and less active people.
Innumerous scientists confirm that nutrition and dietary supplementation can deeply affect molecular and cellular processes that occur in the body during the exercise and the recovery process. This brief review analyzes the potential for performance enhancement through protein supplementation ingestion, and the importance of nutrition education for sports supplement users.
Serious athletes push their limits to become stronger and faster. A key feature of physical activity is that it increases the rate of energy use, causing athletes to have a greater need for energy nutrients (carbohydrate, protein, and fat) (Bernardot, 2006). The practice of sports nutrition has evolved over the years and has become increasingly complex. At one time, the focus was on achieving a high protein intake, especially animal protein. This idea is attractive since it is easy to believe that a high intake of protein will support the building and repair of muscle proteins. In the latter part of the last century, the focus shifted. It was recognized that an adequate intake of protein is essential for all athletes; however, the role of carbohydrate and water became the focus of sports nutrition strategies (Maughan, 2011). Serious athletes recognize that adoption of a dietary strategy that meets their nutritional goals will maximize the possibility of competitive success. The athletes who correctly match energy and nutrient needs to their training schedules are ultimately the ones who succeed.
Carbohydrates are the best fuel for athletes because they take less oxygen to burn than protein or fat. You'll be able to exercise harder, both during training and competition, when you eat enough carbohydrates. Each gram of carbohydrate provides 4 calories.