Nutritional Strategies

Evaluate the appropriateness of nutritional strategies that aim to improve sport and exercise participant’s performance.

Oxford English Dictionary (2003) defines a strategy as: 'a plan of action designed to achieve a long-term or overall aim'. So a nutritional strategy is a plan of action of what type of foods to eat, the quantities to eat them in and how long to do this for.

A very popular nutritional strategy used by many endurance athletes is called 'Carb loading' or 'Carbohydrate loading'. Class Notes (2015) describes Carb loading as: 'eating a higher than usual carbohydrate intake for 1-4 days prior to an event while tapering training'.

Jacques Delorme (2012). The video above describes the basics of carb loading and explains how athletes are using it as strategy for their particular sport.

Here is a diagram to show the theory of Carbohydrate loading. As you can see when we get to around 5 or 4 days before an event exercise/training decreases dramatically and the amount of carbohydrates eaten should increase heavily. 

The theory behind this is explained by Class Notes (2015) as follows: 'Muscle glycogen levels are normally in the range of 100-120 mmol/kg ww (wet weight).  Carbohydrate loading enables muscle glycogen levels to be increased to around 150-200 mmol/kg ww.  This extra supply of carbohydrate has been demonstrated to improve endurance exercise by allowing athletes to exercise at their optimal pace for a longer time.  It is estimated that carbohydrate loading can improve performance over a set distance by 2-3%.'

Therefore, the point of carbohydrate loading is to boost muscle glycogen levels to be able to perform over a longer period of time at a higher intensity. The sports performers who could benefit from carb loading are performers who are competing at a moderate or high intensity for over 90 minutes. For example, marathon runners, cyclists and endurance swimmers. 

Kara Corey (2014). The video above shows a marathon runner 'carb loading' before an upcoming marathon. The important part of the video is where the marathon runner says she has reduced her training hours and on the day before the marathon she is doing no training at all. The most common mistake by athletes is that they increase the amount of carbs but don't reduce training. Not resting will not give the full benefit of boosting the muscle glycogen stores as the majority of carbs will be used for training rather than being saved for the event.

A less scientific strategy is 'Food Preparation', this where an athlete or sport performer prepares several meals for each day which will contain sufficient nutrients required for them. The video below shows the daily food intake for a rugby player. It shows the importance of not just eating Protein and Carbohydrates and to always include fruit and vegetables in your diet. The video explains how preparing meals can improve your diet and sport performance.

James Haskell (2014). By not preparing foods you may miss out on nutrients you need or over intake on some. 

Another strategy to follow is called the Harris Benedict equation. 'The Harris Benedict Equation is a formula that uses your BMR and then applies an activity factor to determine your total daily energy expenditure (calories).' (Class Notes 2015). The video below describes the formula used and how to apply it to different sports performers. 

(Class Notes 2015) The diagram above shows in detail the formula used for males and females and how to work out your BMR (Basal Metabolic Rate) and PAL (Physical Activity Levels). 

The Harris-Benedict equation is a good starting strategy to use to find out a fairly accurate BMR. This will help to review if a sports performer has had enough calories or too many. However, the equation doesn't take into account lean body mass, therefore people with high lean body mass may under estimate calorific needs and obese people may over estimate calorific needs. It is also hard for a sports performer to define their activity level into lightly active, moderately active, very active and extremely active; it is too vague description without any numbers to back up each category.

Another nutritional strategy is to use Sports drinks rather than water to hydrate yourself before, during and after exercise. 

Hypertonic Sports Drinks

Hypertonic drinks contain over 8%t of carbohydrate and have a slower rate of absorption. Although they provide a source of carbohydrate replenishment, they are not ideal for optimal rehydration and may need to be consumed with other fluids. These are best used in the recovery stage after exercise.

Isotonic Sports Drinks

Isotonic drinks contain the same concentration of glucose to water as is found in your blood: 4–8% or up to 8g per 100 ml of water. They usually contain sodium, which makes them quicker to be absorbed into the bloodstream. An isotonic drink is useful whenever exercise has been prolonged or during warmer weather when sweat loss is higher. They can also be used effectively before exercise.

Hypotonic Sports Drinks

Hypotonic drinks have a lower concentration of carbohydrates and are more diluted than isotonic or hypertonic sports drinks. They contain less than 4% carbohydrate (4g per 100 ml of water) and are generally easily absorbed and well tolerated. Although water is adequate for non-endurance training or when sweat losses are small, these drinks may encourage fluid replacement through enhanced taste.

Class Notes (2015)

The above reference shows what sports drink provide on top of what water can. Water is considered sufficient for low intensity and short duration exercise however for high intensity and endurance sports a sports drink can improve sport performance as they provide carbohydrates (for energy), glucose and hydration.

It is important to always consider that your nutritional requirements are different from everybody else. Therefore, always seek professional advice from a nutritionist or doctor before implementing any strategies first.

References:

Oxford English Dictionary (2003) Strategy [Online] Available from: http://www.oxforddictionaries.com/definition/english/strategy [Accessed 2015]

Kara Corey (2014) Day of Eating | Pre-Marathon Carb Load [Online Video] Available from: https://www.youtube.com/watch?v=sG4LIJJisS0 [Accessed 2015]

Class Notes (2015) Nutrition for Sport Performance [Online] Available from http://vle.chesterfield.ac.uk/course/view.php?id=3196 [Accessed 2015]

Jacques Delorme (2012) Sports Nutrition - Carb Loading [Online Video] Available from: https://www.youtube.com/watch?v=5_1QXEbFjvk [Accessed 2015]

James Haskell (2014) The Daily Food Consumption of a Rugby Player [Online Video] Available from: https://www.youtube.com/watch?v=geYW-WWBIjI [Accessed 2015]

Claire Adam (2015) Harris Benedict Equation [Online Video] Available from: https://www.youtube.com/watch?t=60&v=0M6xfC2kDNY [Accessed 2015]

Class Notes (2015) Limitations of The Harris-Benedict Equation [Online] Available from: http://vle.chesterfield.ac.uk/course/view.php?id=3196 [Accessed 2015]

Class Notes (2015) Hydration Through Sports Drinks [Online] Available from: http://vle.chesterfield.ac.uk/course/view.php?id=3196 [Accessed 2015]

Optimal Hydration

Dehydration is where the body has less water and fluids than what is required. This can have adverse effects on bodily functions and sports performance.

'Water is essential for life. It accounts for about 60% of our body weight and performs crucial roles such as carrying nutrients and waste products between our major organs, helping regulate body temperature, lubricating our moving parts, and acting as a shock absorber.' Derbyshire E (2015)

Derbyshire E (2015) states that: 'our brains are 73% water, poor hydration can have an adverse effect on how our brains function.'

These refrences support the importance of hydration for everybody, especially sports performers who are vunerable to dehydration. 

The video above is from the leading sports drink brand Lucozade, it explains the benefits of hydration and what it can do to your performance.

'Dehydration of greater than 2% loss of body weight increases the risk of nausea, vomiting, diarrhoea, and other gastro-intestinal problems during exercise. Dehydration reduces the rate of fluid absorption from the intestines, making it more difficult to reverse the fluid deficit.' Class Notes (2015) This refrence shows the small margin it takes to become dehydrated and how difficult it is to re hydrate afterwards. Exercise causes sweating which means fluids are lost from the body, if not replaced by water or sports drinks this will result in a drop in bloood volume. This means the heart will have to work harder to circulate blood which can mean a higher chance of muscle cramps and dizziness.

It is so important for sports performance that during the FIFA World Cup 2014 in Brazil, FIFA sanctioned that in certain matches that play be stopped for 3 minutes in both halves in order for teams and officials to have a 'drinks break'.

Here are some pictures from the last sixteen knockout game between The Netherlands and Mexico in Fortaleza. Temperatures exceeded 32C and drinks breaks were taken around th 30th and 75th minutes. FIFA allowed this to happen from pressure they recieved from Head coaches and managers of the participating countries. 

This is further evidence of how important it is to hydrate as the biggest sporting body in the world is prepared to stop a World Cup match twice in order to take on fluids.

Hyponatraemia

Class Notes (2015) defines Hyponatremia as 'a rare condition that happens when there is too little sodium in the body. It can occur in athletes who drink too much water.' The likelyhood of this happening in dry hot conditions is small as it would be hard to drink too much due to the execissive sweat loss. It is more common in cool damp conditions where sweat loss is lower. Endurance athletes have a higher risk of Hyponatraemia and it can have serious effects on health. Cells, Lungs and Brain can swell from excessive amounts of water in your body also leading to confusion and headaches. 

It is important not to over hydrate for any sports performer as physically it makes you heavier and you can feel bloated; this can cause an athlete to feel uncomfortable when running and slow them down considerably. If the sport requires a lot of hand eye coordination and is a fine skill, then headaches and confusion are going to hinder your performance considerably. For example, if you watch a Snooker or Darts player they will always have a jug of water next to the board or table to drink from between shots. 

Class Notes (2015) The above table shows the fluid guidelines for before, during and after exercise. This will change depending on the type of sport and environment in which its being played in. For example, if the sport is intense and a lot of sweat is being lost, combined with hot sunny conditions then the sport performer may want to take on extra fluid during the exercise or implement more breaks for fluid replacement.

Class Notes (2015) Above shows how to work out sweat losses and sweat rates. To give you a more accurate guideline, some professional athletes will work out their sweat losses and sweat rates in order to know how much fluid to take. Every athlete is different and by knowing the exact amount of fluid intake required for you body will maximise your performance as the body doesn't have too much or too little fluid. This may only be a slight advantage but if opposition athletes have taken too much they may feel heavy and bloated meaning you can move quicker and sharper than them. Or if they haven't hydrated enough they will become weak, slower and not as mentally quick; all disadvantages to the opponent.

References:

Derbyshire E (2015) The Essential Guide to Hydration [Online] Available from: http://www.naturalhydrationcouncil.org.uk/wp-content/uploads/2012/06/The-Essential-Guide-to-Hydration-AUG1.pdf [Accessed 2015]

Lucozade Sport (2012) Lucozade Sport Performance Day 2012 - Hydration [Online Video] Available from: https://www.youtube.com/watch?v=WzB-sPj9uOQ [aCCESSED 2015]

Class Notes (2015) Hydration and Sports Drinks [Online] Available from: http://vle.chesterfield.ac.uk/course/view.php?id=3196 [Accessed 2015]

Class Notes (2015) Nutrition for Sports Performance [Online] Available from: http://vle.chesterfield.ac.uk/course/view.php?id=3196 [Accessed 2015]

Fats for Sports Performance

According to Class Notes (2015): Fats are 'a nutrient and a source of energy and they are required as part of a healthy diet'. They are important to us because they 'add taste and texture to foods, makes us feel full longer and help absorb fat-soluble vitamins'. Class Notes (2015)

Fats are important to include in your diet, however in small quantities; this is because they have useful functions however they can hinder the body if the quantity increases.

Polyunsaturated fats (PUFA)

Contain Omega 3 which is important as the body cant produce it itself. Commonly found in fish, eggs 

Monounsaturated fats (MUFA)

Help to decrease the risk of heart disease

Examples: Olive oil, peanuts and canola oil.

Saturated fats (SFA)

High in Saturated fat foods can increase the risk of heart disease. 

Examples: Butter, cakes and pastries.

Trans fats (TFA)

Act like saturated fats in the body and come from commercially prepared foods.

Examples: French fries, donuts and pizza.

Sports Performers:

20-35% of you total Calorie intake per day should come from fats, however this varies depending on the individuals exercise or training programme.

My recommended daily calorie intake is around 3000 on a moderately active day, which means the total calories I should receive from fats is between 600-1050.

According to Class Notes (2015) fats 'helps us absorb fat-soluble vitamins' this is important as our body needs fat-soluble vitamins for various processes. We know fat-soluble vitamins can help the immune system and strengthen bones. It is important for everybody to include some type of fats in their diet at the correct amount, in order for these fat-soluble vitamins to be useful. 

In terms of a Sports performer it is even more important to have a good immune system and stronger bones. A golfer travels from country to country every week playing tournaments therefore if they are ill it will be difficult to rest it off as they play for four days straight. It is important for a golfer to have a strong immune system which would mean getting the right fat-soluble vitamins in their diet. In order for these vitamins to be absorbed and used by the body the golfer would have to intake some fats.

References:

Class Notes (2015) Fats The Basics [Online] Available from: http://vle.chesterfield.ac.uk/course/view.php?id=3196 [Accessed 2015]

Protein for Sports Performance

According to Class Notes (2015) : 'Proteins are molecules that have many enzymatic and structural functions related to the growth, maintenance and repair.' 

Class Notes (2015) states: 'The goal of dietary protein intake is to contribute the amino acids (EAA’s) necessary to assimilate proteins for skeletal structures and hormones, function as cell membrane receptors and maintain fluid balance.'

Given the definition of what a protein is they are an integral part of any diet. Even more so for a sports performer as proteins primary function is to grow maintain and repair muscle.

Required protein intake is measured by nitrogen balance. For example if the amount of protein intake is positive this is called protein synthesis and if the intake is negative (not enough then this is called protein degradation. 

The video above explains the effects of a positive or negative nitrogen balance. During protein synthesis anabolic processes occur causing muscles to repair and build after exercise. However during protein degradation this is where the muscles have been used during exercise but not repaired by the intake of protein. If you went to the gym and did some strength training but didn't intake protein afterwards the muscles would be damaged and catabolic processes would occur. This shows the importance of protein regardless if your work out or not.

'The RDA (Recommended Daily Allowance for protein in normal sedentary individuals is 0.8g/kgBW (1kg=2.2lbs)' (Class Notes 2015)

However all athletes need an increased amount of protein in their diets compared to sedentary individuals no matter what the sport is. Below is what I researched to show their are different RDA's of protein for contrasting sports performers.

Who? How Much?

RDA for sedentary adult 0.8 g/kg BW/day 
Physically active adult 1.0 g/kg BW/day 
Endurance athlete 1.2 - 1.4 g/kg BW/day 
Strength athlete 1.4 - 1.8 g/kg BW/day 
Adolescent athlete 1.0 - 2.0 g/kg BW/day 
Maximum for adult athletes up to 2.0 g/kg BW/day 

Chowdhury Zaman M.B.B.S., M.S., Dr. Ken Lin, Ph.D. Biochemistry, William O’Neill (2007)


'Protein intake equal to 10-20% of total calories will meet the protein requirements of most athletes. The type of sport and total calorie intakes influence protein requirements. For example, cross country skiing and ice hockey both require a high level of energy intake to meet energy expenditures.' Chowdhury Zaman M.B.B.S., M.S., Dr. Ken Lin, Ph.D. Biochemistry, William O’Neill (2007)

Using the reference theory above I have calculated my protein RDA below:

Sports Performer	Example	Recommended Daily Allowance	My RDA Protein
Sedentary Individual	Exercise less than once a week	0.8 x KgBW	63.2g
Endurance Athlete	Marathon Runner Footballer Basketball player	0.8-1.2 x kgBW	94.8g
Strength Trainer	Power lifter	1.2-1.8 x KgBW	142.2g

If athletes consume 15% of their calories as protein are they getting enough to promote an increase in FFM?

On a day where I complete doerate exercise I require around 3100kcal.

15% of 3100 = 465kcal
465kcal / 4kcal = 116g
116 / 79kg = 1.4g per kg/BW

The idea of consuming 15% of your diet as protein works well as it links in well with the RDA numbers produced earlier. On a moderate exercise day I require 116g of Protein whereas in the study above I varied between 94-142g of protein per day depending on exercise. This number fits in with previous evidence and recommendations therefore it could be a quicker way for an athlete to work out how much protein to intake.

Protein Sources:

Complete Proteins (Contain all 9 essential amino acids EAA's)

Examples: Complete Proteins (Meat, Fish and Diary products)

Incomplete Proteins (Contain some of the 9 essential amino acids)

Examples: (Nuts and Grains)

If an athlete is vegetarian or vegan they can supplement meat and fish with synthesized pure amino acids. They can also use protein shakes to ensure they are receiving all 9 essential amino acids.

Refrences:

Class Notes (2015) Athletic Performance and Protein Intake [Online] Available from: http://vle.chesterfield.ac.uk/course/view.php?id=3196

Christine Dobrowolski (2014) 7.4 Protein: Nitrogen Balance [Online] Available from: https://www.youtube.com/watch?v=9NPGU5XSc54 [Accessed 2015]

Chowdhury Zaman M.B.B.S., M.S., Dr. Ken Lin, Ph.D. Biochemistry, William O’Neill (2007) A Review of the Importance of Amino Acids in Sports Performance [Online] Available from: http://vle.chesterfield.ac.uk/pluginfile.php/283028/mod_resource/content/1/Protein%20%28Amino%20Acids%29%20and%20Sports%20Performance.pdf [Accessed 2015]

Carbohydrates for Sports Performance

The primary purpose for carbohydrates is to provide energy for the brain and muscles. It is also the preferred macronutrient used by the body for energy so it is an important part of a sports performers diet. Carbohydrates are stored within the muscles and liver in the form of glycogen.

Glycemic Index

Carbohydrates can be separated into three groups which are part of the glycemic food index. The first category is the high glycemic index foods and are typical foods such as bagels, white bread and doughnuts. The second category is called moderate glycemic index foods and includes white rice, cereal and pita bread. The final category is called low glycemic index foods and examples of these foods would be beans and milk. 

The reason carbohydrates are split into these categories is because our body reacts differently due to the contents of the nutrient. For instance, this diagram shows a high glycemic food (white bread) and a moderate-low glycemic food's effect on our blood sugar response. Due to high glycemic foods having more glucose in them, our blood sugar levels increase rapidly after eating and then suffer a big drop after an hour. Whereas, a moderate-low glycemic food increases blood sugar levels more evenly over a longer period of time. This is important for a sports performer to understand because different types of carbohydrates will give us different functions. Depending on what sport you are participating in it may be beneficial to consume different types of carbohydrates.

Pre Exercise CHO Requirements

The aim of a pre exercise meal is to maximise the muscle and liver glycogen stores ready to be used during exercise.

A power lifter is performing at a high intensity for a short period of time. More glucose will be expended within a short period of time; therefore it needs to be provided priory to exercise. It would be more beneficial for a power lifter to consume high glycemic foods around 15 minutes before competing. This is because they require a big boost of energy to work at high intensity, high glycemic foods would be perfect for this under an hour. 

Contrasting this sports performer with a marathon runner who is working at a less intensity but require to last longer; because of the lower intensity the carbohydrates need to provide energy for the marathon runner for over 2 hours. Therefore, moderate to low glycemic foods should be apart of the pre exercise meal. The ideal time to eat prior to exercise is 2-4 hours.

Pre Event Nutrition Preparation (2015) states: 'Research suggests that endurance performance is improved when athletes consume a substantial amount of carbohydrate (200–300g) in the 2–4 hours before exercise.'

Therefore, consuming 1-5 grams of Carbohydrate per KG of BW 2-4 hours before exercise would benefit a sports performers performance. If I followed this guideline in my practice I should include between 79-395 grams of CHO in my pre exercise meal.

The video above gives an insight from a professional nutritionist and dietitian on the types and amounts of food that is good to eat before exercise.

Post Exercise CHO Requirements

According to IOC (2015) 1-2 grams of CHO per KG of BW is recommended to be included in your post exercise meal. The meal should be consumed up to 4 hours after completing exercising. Post exercise I should have 79-158 grams of carbohydrate in my meal. 

Refrences:

IOC (2015) Carbohydrate for competition [Online] Available from: http://vle.chesterfield.ac.uk/course/view.php?id=3196 [Acessed 2015]

LIFESTYLE MEDICINE (2013) The Glycemic Index Explained [Online Video] December 2013 Available from: https://www.youtube.com/watch?v=F1YDR2S7SPU [Acessed 2015]

MonkeySee (2013) What to eat before exercise [Online] Available from: https://www.youtube.com/watch?v=ou37Js1mzEU [Accessed 2015]

Class Notes (2015) Carbohydrate for Sport Performance [Online] Available from: http://vle.chesterfield.ac.uk/course/view.php?id=3196

Pre Event Nutrition Preparation (2015) Pre Event Preparation [Online] Available from:  http://vle.chesterfield.ac.uk/pluginfile.php/283037/mod_resource/content/1/Pre-Event%20Nutritional%20Preparation.pdf

Micronutrients - Breakdown of Vitamins and Minerals

Definition: 'Any substance, such as a vitamin or trace element, essential for healthy growth and development but required only in minute amounts.' (Collins English Dictionary 2003) 

As well as vitamins, micronutrients can be found in minerals which are natural, organic and come from the ground. Whereas, vitamins are substances that cant be made by the body and need to be provided by diet. Vitamins do not provide energy but are required for many processes within the body. There are two types of vitamins: fat solubles and water solubles.

Vitamins A, D, E and K are fat soluble and Vitamins B and C are water soluble.

What processes within the body do vitamins help with?

Vitamin A:

- Normal Iron metabolism

- Normal Vision

- Immune system

Examples: Carrots, Cod liver oil, Sweet potato, Pumpkin

Life stage group	RDA Adequate intakes (AI*) μg/day	Upper limit μg/day
Infants 0–6 months 7–12 months	400* 500*	600 600
Children 1–3 years 4–8 years	300 400	600 900
Males 9–13 years 14–18 years 19 – >70 years	600 900 900	1700 2800 3000
Females 9–13 years 14–18 years 19 – >70 years	600 700 700	1700 2800 3000
Pregnancy <19 years 19 – >50 years	750 770	2800 3000
Lactation <19 years 19 – >50 years	1200 1300	2800 3000

Institution of medicine (2000)

Vitamin D:

- The absorption and use of calcium and phosphorus

- Blood calcium levels

- Bones and teeth

- Muscle function

- Immune system

Examples: Sun light, Oily fish, Supplement tablets

Vitamin E:

- Antioxidant

- Protect cells against oxidative damage

- Excess Carbon

Examples: Wheat germ oil, Sunflower oil

mg/day	Age
Infants
4	0 to 6 months
5	7 to 12 months
Children
6	1 to 3 years
7	4 to 8 years
11	9 to 13 years
Adolescents and adults
15	14 and older

 National Institute of Health (4 May 2009)

Vitamin K:

- Blood clotting

- Maintenance of normal bones

Examples: K1 - Kale, Cabbage, Brussels sprouts K2 - Meat and Diary products

Vitamin B:

- B1 - Thiamine releases of energy from carbohydrates

- B2 - Riboflavin releases energy from carbohydrates, fats and protein

- B3 - Niacin releases energy from food, reduction of tiredness and fatigue

- B6 - Pyridoxine nervous system, helps regulate blood processes

- B12 Cyanocobalamin red blood cells, helps regulate blood levels

B1

B2

B3

B6

B12

(Wikipedia 2015)

Vitamin C:

- Immune System

Examples: Kakadu plum, lackcurrant, Red pepper, Parsley, Broccoli, Redcurrant

References:

Collins English Dictionary (2003) micronutrient [Online] Available from: http://www.thefreedictionary.com/Micronutrients [Accessed 2015]

National Institute of Health (4 May 2009) Vitamin E fact sheet [Online] Available from: http://ods.od.nih.gov/factsheets/VitaminE-HealthProfessional/ [Accessed 2015]

Institution of Medicine (2000) Daily reference intakes [Online] Available from: http://www.iom.edu/Global/News%20Announcements/~/media/474B28C39EA34C43A60A6D42CCE07427.ashx [Accessed 2015]

Wikipedia (2015) B Vitamins [Online] AVailable from: http://en.wikipedia.org/wiki/B_vitamins [Accessed 2015]