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Nutrition and Performance. Exercise and Performance Tutorial Presentation. By…. Ice Breaker – Famous Faces. Who am I?. Who am I?. Who am I?. Who am I?. http://www.youtube.com/watch?v=URghSgfHrh0 . Who am I?. Who am I?. Who am I?. Who am I?. Who am I?. Types of Carbohydrates:.
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Nutrition and Performance Exercise and Performance Tutorial Presentation
Who am I? • http://www.youtube.com/watch?v=URghSgfHrh0
Types of Carbohydrates: Monosaccharides: (Simplest carbohydrate) -Glucose -Fructose (in fruit and honey) -Galactose Disaccharides: (a carbohydrate composed of 2 Monosaccharides) -Lactose (galactose and glucose) -Sucrose (fructose and glucose) -Maltose (glucose and glucose) Polysaccharides: (complex carbohydrates. Made up of many Monosaccharides and bonded together.) -Glycogen (energy stores in animals and humans-primarily in liver and muscles) -Starch and Fibre (carbohydrates stored in plants. In fruit, seeds, rice, wheat, corn, grains etc)
Role of Carbohydrates in Sports: -Carbohydrates are a major energy source during sport and exercise. -When consumed, blood glucose levels rise and are used as energy for working muscles. -Glycogenesis- blood glucose is converted into glycogen and stored in the muscles and liver. -Glycogen stores have a large impact on sports performance, as muscle glycogen may decrease or increase due to carbohydrate consumption. -Glycogenolysis, glycogen is broken down and converted back to the blood as glucose. This will be the primary source for the body’s energy.
Glycaemic Index: What is it? • Glycaemic Index (GI) is the index for comparing the blood glucose response from the ingestion of various foods. • The more complex the carbohydrate, and the more fat, protein and fibre in the food the lower the GI level will be.
Glycaemic Index: continued… • GI values can be interpreted intuitively as percentages on an absolute scale and are commonly interpreted as follows:
Hyper and Hypoglycaemia: • Hyperglycaemia occurs when plasma glucose levels are elevated, such as after a meal, the pancreas receives signals to release insulin into the blood. It is generally found in people with diabetes. • Hypoglycaemia is caused by a low blood glucose level during and after exercise as the liver fails to release glucose at a rate that can keep up with glucose consumption. An example would be consuming too much sugar causes a come down effect.
Hyper and Hypoglycaemia: What is the difference between hypoglycaemia and hyperglycaemia? • Hypoglycaemia is caused by having low levels of glucose ie. Too much sugar causes a come down effect. • Hyperglycaemia (high blood sugar) is a condition, in which an excessive amount of glucose circulates in the blood plasma.
Hyper and Hypoglycaemia: How do we remember the difference between the two? • Hypo = Low • Hyper =High
Rebound Hypoglycaemia: How/why it happens? - Athletes consume High GI carbohydrates 15-45 minutes before exercise. - Insulin is released, and its levels within the body elevated. - In response to these insulin levels, 'glucose uptake by the muscles reaches an abnormally high rate' (Wilmore et al. 2008: 332) leading to low blood glucose levels = Hypoglycaemia.
Rebound Hypoglycaemia: Why is it detrimental to sports performance? - This 'can lead to early exhaustion by depriving the muscle of its primary energy sources' (Wilmore et al. 2008: 332). (Wilmore et al. 2008: 333)
Rebound Hypoglycaemia: How to avoid it? - Ensure that High GI carbohydrates are not taken within the 15 - 45 minute period before commencing exercise. - Research indicates (Vegetarian Nutrition 2008) that endurance can be improved taking carbohydrates 1-4 hours before exercise. - Take a lower concentrated carbohydrate substance, ie. less than 6% - Liquid Carbohydrates can be consumed late in a long duration exercise, without causing Rebound Hypoglycaemia.
Blood Glucose Loading: • Is the carbohydrate intake directly before competition. • A pre-competition meal should be consumed at least two hours before competition. • A pre-competition mal can prevent hunger and provide essential energy fuel for competition. • Recommended pre-competition meal is 200-500 calories
Carbohydrate Loading: • Is not just eating flat out!! • Rather it is the process used by most endurance athletes to boost glycogen stored in days leading up to an event. • Can increase the distance over a set period of time by 2-3% (AIS 2004)
Carbohydrate Loading: • Two types: • Strict (Old theory) • General (Modern day)
Carbohydrate Loading: Strict (6-7days): Day 1: Exhaustive bout off exercise Days 2-4: Eat fat and protein foods 3 times per day with minimal exercise Days 5-7: Eat a carbohydrate rich diet with minimal exercise Taken from AIS (2004) and Wilmore et al. (2008)
Carbohydrate Loading: General (3-4 days): • Similarly to step 3 of Strict just eat a carbohydrate rich diet with minimal exercise for the 3-4 days leading up to an event. • Research found that similar if not better results were produced by athletes using this variation of the strict protocol. Taken from AIS (2004) and Wilmore et al. (2008)
Carbohydrate Loading: What does a high carbohydrate rich diet look like? - 400-700g per day - The following diet is suitable for a 70kg athlete aiming to carbohydrate load. - Taken from AIS (2004)
Carbohydrate Loading: Breakfast: • 3 cups of low-fibre breakfast cereal with 11/2 cups of reduced fat milk • 1 medium banana • 250ml orange juice
Carbohydrate Loading: Snack: • toasted muffin with honey • 500ml sports drink
Carbohydrate Loading: Lunch : • 2 sandwiches (4 slices of bread) with filling as desired • 200g tub of low-fat fruit yoghurt • 375ml can of soft drink
Carbohydrate Loading: Snack: • banana smoothie made with low-fat milk, banana and honey • cereal bar
Carbohydrate Loading: Dinner: 1 cup of pasta sauce with 2 cups of cooked pasta • 3 slices of garlic bread • 2 glasses of cordial
Carbohydrate Loading: Late Snack: • toasted muffin and jam • 500ml sports drink
Experiment Time: • 4 Volunteers • 2 Females & 2 Males • 2 x Placebo substances • 2 x 12.6% glucose substances (doubles strength energy drink)
Experiment Time: • Each volunteer will run for 20 minutes. • Each volunteer will wear a HR monitor (remember to spit on the pads) • Then we will compare results and investigate the data.
Experiment Time: • Class split into 4 groups as a support team to each volunteer. • Each team is responsible for collecting data shown on page 53 of lab manual.
Experiment Time: Team Roles: • 1 Timer keeper • 1 H/R monitor • 1 RPE monitor (refer to graph on pg 52 of lab manual) • 1 Warm up and 1 warm down coach (OHS) • 1 lap counter • Encouragers/cheerers
Experiment Time: LETS DO IT!!!!
Discussion Time: • Fill in graph page 55 of lab manual • What effect did the ingestion of glucose have on performance? • What are the potential benefits of pre exercise ingestion of glucose? Why? • What are the potential negative consequences of pre exercise glucose intake? Why? • Based on what we have found, and the information in the text, for what activities would you recommend pre exercise ingestion of glucose? • And at what concentration/amount?
THE END!!! Thanks to everyone who has participated.
References Department of Sport nutrition, AIS (2004) AIS Sports Nutrition: Carbohydrate Loading [online]. Available: http://www.trainingsmartonline.com/images/Free_Triathlon_Articles/carbohydrate_loading.pdf[Accessed 5 August 2008] McArdle, W., Katch, F. & Katch, V. (2006) Essentials of Exercise Physiology. 3rd Ed. USA: Lippincott, Williams Wilkins.Vegetarian Nutrition (2008)[online].Available: http://www.vegetariannutrition.info/vn/vn_athletes.htm [Accessed 09 Aug 2008].W. B. Saunders Company (1999) Role of Carbohydrate in Physical Activity. Clinics in Sports Medicine. 18(3): 469-484Wilmore, J.H., Costill, D. L., & W. Larry Kenney (2008) Physiology of Sport and Exercise, (4th Edition) Human Kinetics, Champaign, IllYager, Zali (2008) In an email communication on 6 August 2008: Blood Glucose Loading. Available email: Z.Yager@latrobe.edu.au [Accessed 6 August 2008]Yager, Zali (August 2008) Exercise and Performance lecture [3] notes: Nutrition for Exercise. Available: http://webct.latrobe.edu.au/webct/urw/lc9140001.tp0/cobaltMainFrame.dowect [Accessed 4th August 2008]All images sourced from Google Images and Microsoft Clip Art