Should an ultra-marathon runner ‘carb-load’ before an event?
Introduction Carbohydrate-loading or carbo-loading is a diet that consists of carbohydrates in a high consumption to increase an athlete’s performance. Carbohydrates are the body’s primary source of energy and with eating this food group, it allows for energy to be sustained for long distance athletes.
The carbo-loading diet involves training and nutrition that maximises ones muscle glycogen storage prior to an endurance competition. It was originally said that there are two phases to carbohydrate loading; the depletion phase and the loading phase. The depletion phase consists of 3-4 days of high training and low carbohydrate intake in order to stimulate the enzyme glycogen synthase. This is then followed by the loading phase which comprises of 3-4 days of rest with high carbohydrate intake. The two phases enhance the muscles carbohydrate storage beyond the body’s usual inactive levels. The depletion phase was then thought to be unnecessary and so now only the ‘loading phase’ is needed in order to evaluate muscle glycogen levels.
Carbohydrates are essential or the body to function as they are converted into glucose by the body. The glucose is then dissolved in ones bloodstream and diverted to the parts of the body that use the most energy, such as the muscles and the brain. Eating these foods before a competition allow the blood-glucose levels to be maintained throughout the event. Then, from this, no further carbohydrate consumption is needed during the course of the event.
Carbohydrate loading increase muscle glycogen levels by 30-100 mmol/kg ww which improves performance over a set distance from 2-3%. Improving glycogen levels allows athletes to exercise at their ideal pace for a longer period of time.
In contrast to carbohydrate loading, Professor Tim Noakes, states how eating little carbohydrates, no more than consuming 50 grams a day, and replacing this with healthy fat intake with improve one’s health.
Any athletes exercising continuously at a fairly high intensity for 90 minutes of longer should carbohydrate load. The main sports where athletes should carbohydrate load are; cycling, marathon running, long distance triathlons, skiing and endurance swimming. It is not ideal for team sports where matches are played every 3-4 days.
Literature Review 1. Gallop, R. (2003). The Problem 1: Carbohydrates. The GI Diet. Canada. Pp. 7-14
This article focuses on how carbohydrates are required for ones diet to be healthy one. Many people cut down or even cut out carbohydrates in their diets when focusing on weight loss. Instead of this, one should choose good carbohydrates rather than bad carbohydrates. The consumption of carbohydrates have increased over the years, especially the intake of grans. They are rich in fibre, vitamins and minerals, including antioxidants which are believed to protect the body against heart disease and cancer.
According to Gallop, R (2003), ‘carbohydrates are the primary source of energy for your body’. This is a very valid statement as carbohydrates are essential or the body to function as are converted into glucose by the body. The glucose is then dissolved in ones bloodstream and diverted to the parts of the body that use the most energy, such as the muscles and the brain.
This is a reliable source as the information is relevant to the researcher’s hypothesis; that carbohydrates are important in providing the body with long, sustainable energy. It is a valid source as author, Gallop, R, graduated from the University of Oxford which is one of the most prestigious Universities in the world. It is a useful source as it provides necessary information about carbohydrates however is limited in the sense that the book, The GI Diet’s, main focus is on low GI food rather than carbohydrates which is only focused on in one chapter. The source is also outdated as it was published 12 years ago and this information may have changed slightly due to recent sciences however, on the contrary, it shows how carbohydrates have been the main source of energy for many years.
2. AIS Sports Nutrition. (2009). Carbohydrate loading. Available at: http://www.ausport.gov.au/ais/nutrition/factsheets/competition_and_training/carbohydrate_loading [Accessed on 6 February 2015].
This source states how carbohydrate loading was a strategy developed in the 1960’s that involves training and nutrition that maximises ones muscle glycogen storage prior to an endurance competition. Carbohydrate loading increases muscle glycogen levels by 30-100 mmol/kg ww which improves performance over a set distance from 2-3%. Improving glycogen levels allows athletes to exercise at their ideal pace for a longer period of time.
Any athletes exercising continuously at a fairly high intensity for 90 minutes of longer should carbo-load. The main sports where athletes should carbohydrate load are; cycling, marathon running, long distance triathlons, skiing and endurance swimming. It is not ideal for team sports where matches are played every 3-4 days. It suggests that females are less responsive to carbohydrate loading, especially during the follicular phase of their menstrual cycle, however, this topic has not had enough research done to prove this speculation.
This article states the common mistakes made when carbohydrate loading which include; not eating enough carbohydrates, not reducing the amount of intense exercise 3-4 days before the competition, not being prepared to gain weight, or using carbohydrate loading as an excuse to eat everything in excess which includes mostly fats and this defeat the point of ‘carbohydrate’ loading.
This is a valid source as it was written by sports nutritionists whom specialize in both nutrition and sports which allows the source to be beneficial for both these aspects of the researcher’s topic. It is a useful source as it gives necessary information, all relating to the topic ‘Should an ultra-marathon runner ‘carb-load’ before an event?’ however, it does provide extra information such as how females benefit to this diet as opposed to males. The limitations to this source is that it was updated in 2009 and it focuses only on all the positive sides of carbohydrates which could be seen as biased however, all of the information is backed up biologically, proving it to be logical and beneficial.
3. Beresini, E. (2014). The Truth behind the High-Fat-Low-Carb Cult. Available at; http://www.outsideonline.com/fitness/bodywork/the-fit-list/Why-Charity-Races-Are-Losing-Money.html [Assessed on 19 February 2015].
This article concentrates on the banting diet, which is a low carbohydrate, high fat based diet. It states that it is an ideal diet for weight loss however for athletes, it will decrease the pace of your performance. It is in contrast to carbohydrate loading, Professor Tim Noakes, states how eating little carbohydrates, no more than consuming 50 grams a day, and replacing this with healthy fat intake with improve one’s health.
Then an alternate example is given; the Kenyan diet. This diet consists of 78% carbohydrates and Kenyan runners are the greatest long distance runners in the world. Diets play an important role in part of training and preforming at a competitive level. According to Fitzgerald, M (2014) ‘Decades of research indicate that high-carb diets are optimal for endurance and that ingesting carbohydrates during endurance exercise enhances endurance.’
Banting is the key diet to weight loss and improved health as it encourages the body to burn fats rather than fuels. This diet also reduces the risks to many diseases such as heart disease, strokes, diabetes and cancers. The high-fat-low-carb diet makes athletes leaner however it causes them to lose power due to the impairment of the muscles’ ability to burn carbohydrates. Athletes essentially train their bodies to use fats for fuel and decrease the reliance on carbohydrates.
The body needs carbohydrates for fuel when competing at a fast pace and banting, or high-fat-low-carb diet does not permit one’s body to do so. Fitzgerald, M (2014) also states that ‘eating carbs is almost a universal practice among the world’s best endurance athletes.’
This is a fairly recent source which suggests that the information is updated and applicable today. There is however, irrelevant information included in the source. Author, Beresini, E (2014), refers to multiple previous researchers’ information, such as Noakes, T and Fitzgerald, M. This article does give a broad perspective to both high-carbs-low-fats as a diet and the differing diet consisting of high-fats-low-carbs which allows the researcher to see both diets in detail and their effect on athletes. The limitations to this source is that majority of it is backed up evidence from previous researchers, which is information one can acquire from the books written by those researchers. It is also a fairly informal article as the author uses informal language and improper sentences at times.
4. Noakes, T. (2013). Is the banting diet ideal for athletes? Health 24. Available at: http://www.health24.com/Diet-and-nutrition/Nutrition-basics/Tim-Noakes-on-carbohydrates-20120721 [Accessed on 23 January 2015].
This article motivates the biological needs of the Banting diet. It states how it benefits people who suffer from diabetes, such as Mr T Noakes himself, people who are carbohydrate resistant and people who are pre-diabetic. It is when one’s body is unable to clear the bloodstream from the breakdown product and indigested carbohydrate glucose in the liver and muscles. Instead insulin can be put into the body where most of the carbohydrates ingested will be directed straight into fat cells where contributes to progressive weight gain, continuous hunger, tiredness and in time, pancreatic failure as well as diabetes.
This diet should not be seen as a short term fix but rather as a lifestyle as once you go back to your old ways, the lost weight shall be regained within a few weeks. It requires discipline as the brain needs to overcome its ‘addiction’ factor where the brain will produce ‘fake’ symptoms of craving the foods that it is used to. This makes initially starting a diet without carbohydrates difficult. To make this diet easier, it would require a purpose such as suffering from diabetes.
This article suggests how this diet is ideal for slower athletes who compete in the Argus Cycle Tour and Comrades Marathon. With adopting this diet, they will lose the tendency to overeat, which is the opposite effect of carbohydrate loading. These overweight cyclists and runners whom initially eat a large consumption of carbohydrates as according to Noakes’s book Lore of Running (1994) states that ‘athletes must maximise their carbohydrate intakes to optimise their performances.’ However due to their unknown CR their performance results are low, these athletes should consider the banting diet and it will lower their BMI’s and improve their performance times by hours without any additional training.
Without a high carbohydrate intake, you will not perform properly during exercise. It is understood that carbohydrates are relatively ineffective fuels for those suffering from CR so no risk regarding exercise to those with CR will be impaired if they cut their carbohydrate intake, which is what Noakes himself has done. According to Noakes, T. (2013) ‘Instead I am certain that the less carbohydrate that those with CR ingest (both in training and in racing), the better they will perform.’
This is a contradicting source to the previous used sources to show diversity and contradict the researcher’s hypothesis being that ultra-marathon athletes should consume carbohydrates before an event. Professor Tim Noakes has been an author to many sources as well as been referred to in many sources as he has done much research on this topic. This article was for banting, however it was not biased in anyway as it stated how this diet is ideal for specific types of people and is not ultimate for top athletes. This article is a fairly personal source as Noakes gives much of his private input and involves his daily diet as well as his personal exercise results. Noakes refers to his book Lore of Running which is an individual source the researcher used prior to this, both counter act from different sides of the diets yet provide the same information. This is a recent source which means it is up to date and the information is relevant in today’s times.
5. Liesbet, D. Steenkamp, G. (2000). Sports Nutrition. Eating for Sustained Energy. South Africa. Pp. 19-20
Athletes should eat low-GI carbohydrate diets as this gives them sustained energy. Athletes should be eating 1g CHO per kg body weight (depending on the duration and intensity) a few hours before they exercise or compete. The carbohydrate-storing ability in the body is limited, therefore it needs to be reloaded regularly.
This article focuses on how athletes should eat low-GI carbohydrate foods as they give slow release because they are digested slowly which therefore supply energy for hours later after intake. Eating these foods before a competition allow the blood-glucose levels to be maintained throughout the event. Then, from this, no further carbohydrate consumption is needed during the course of the event.
After an event, carbohydrates are crucial within the first half an hour to an hour as the exercised muscles will continue to absorb glucose from the bloodstream which happens at a rapid rate after exercise.
It states how carbo-loading is a legal technique for enhancing an athlete’s performance by eating a high intake of carbohydrates such as bread, potatoes, rice, pasta, at least 3 days before a competition. Authors Liesbet, D. and Steenkamp, G. suggest how this diet is not ideal for everyone, with the alternative diet being Tim Noakes’s banting diet.
Despite this source being published 15 years ago, the information is still valid and useful. This article focuses particularly on carbo-loading which makes it very relevant and beneficial. This source is good as in order to avoid being bias, authors Liesbet, D. and Steenkamp, G. show the alternative diet.
The secondary information I used was previous findings of researchers and used that to put together my research. My research was mostly conducted from articles off the internet and from books and magazines. A well-known, qualified, professor, Tim Noakes, who has investigated this topic broadly. I have used his findings and interviews of his to base my research on and use the results. An example of a website accessed to research Tim Noakes’s information is Health24 which also focuses on the opposite effect of carbohydrates and more on the intake of fats.
Process of findings
A lot of information has been gained through looking at various professors, athletes and dietician’s opinion based research, as well as my own research.
Carbohydrates are stored as glycogen in the lover and in muscles whereas fat is stored under the skin and around internal organs. It can be said that the energy that carbohydrates provide raise the intensity during exercise from 10% to up to 90%. Therefore with filling one’s body storage with carbohydrates, they are increasing their glycogen storage which ensures a larger, sustainable energy.
AIS Sports Nutrition. (2009). Carbohydrate loading. Available at: http://www.ausport.gov.au/ais/nutrition/factsheets/competition_and_training/carbohydrate_loading [Accessed on 6 February 2015].
Beresini, E. (2014). The Truth behind the High-Fat-Low-Carb Cult. Available at; http://www.outsideonline.com/fitness/bodywork/the-fit-list/Why-Charity-Races-Are-Losing-Money.html [Assessed on 19 February 2015].
Gallop, R. (2003). The Problem 1: Carbohydrates. The GI Diet. Canada. Pp. 7-14
Liesbet, D. Steenkamp, G. (2000). Sports Nutrition. Eating for Sustained Energy. South Africa. Pp. 19-20
Noakes, T. (2013). Is the banting diet ideal for athletes? Health 24. Available at: http://www.health24.com/Diet-and-nutrition/Nutrition-basics/Tim-Noakes-on-carbohydrates-20120721 [Accessed on 23 January 2015].
Dengue Fever: Diagnosis and Treatment
Dengue fever is a common tropical infection. This acute febrile illness can be a deadly infection in cases of severe manifestation, causing dengue hemorrhagic shock. In this brief article, I will summarize and discuss the diagnosis and treatment of this disease. For diagnosis of dengue, most tropical doctors make use of presumptive diagnosis; however, the definite diagnosis should be based on immunodiagnosis or viral study. Focusing on treatment, symptomatic and supportive treatment is the main therapeutic approach. The role of antiviral drugs in the treatment of dengue fever has been limited, but is currently widely studied.
Dengue is a significant mosquito-borne infection. An arbovirus named dengue virus is the causative agent. Due to the nature of the mosquito-borne infection, dengue has become a significant public health threat in many developing tropical countries. Dengue had been present throughout tropical regions of the world for more than 50 years. Of several tropical regions, Southeast Asia is accepted as the area with the highest prevalence of this disease. A severe hemorrhagic form of dengue infection has become a leading infectious cause of death for local people in Southeast Asia. Francisco Pinheiro, a former researcher from the Division of Disease Prevention and Control, and the Special Program for Vaccines and Immunization, Pan American Health Organization (DC, USA), said that the highest incidence of dengue could be seen in Southeast Asia, particularly in Vietnam and Thailand, which together account for more than two-thirds of the overall reported cases in Asia. Hence, several groups are now carrying out research and development on dengue infection in this area.
At present, due to the efficient mosquito-borne method by which the virus is transported, dengue is not confined within the tropical region, but is sporadically reported from many nontropical countries. It is accepted that it is now a global issue. In South Asia, there have been many reports of dengue epidemiology coming in from India. An increased incidence among the pediatric population in the over-populated areas can be seen. Dengue infection has also been reported in nontropical regions of Asia, such as East Asia and China. Luo et al. noted that epidemics of dengue fever are closely related to the situation of neighboring countries, especially those is Southeast Asia. This indicated the possibility of importation of viruses from these countries, with the epidemics usually arising due to immigration of dengue patients from endemic areas. Similarly, dengue infections also already extend to Australia and dengue has been accepted as a significant emerging infection of concern in Australia. Outbreak of dengue infection in North Queensland gave great concern to the local CDC. In Queensland, it is advised that general practitioners report all clinically suspected cases of dengue in any arriving travelers. For Africa, America,[9-11] Europe[12-14] and Africa[15-17] the increase in reported cases of dengue highlights the necessity to prepare to combat this viral disease.
Focusing on the natural characteristics of dengue, this acute febrile illness can be deadly in cases of severe manifestation, causing dengue hemorrhagic shock. Patients usually visit the physician on the second or third day after the first appearance of fever, and after self-treatment of the illness by some self-prescribed antipyretic drugs. However, after unsuccessful self-treatment, the patients usually end up visiting the physician with a chief complaint of an unexplained high fever and malaise. In this brief article, I will summarize and discuss the diagnosis and treatment of this disease.
Pathogenesis, Natural History