Lecture 6 - Nutrition for Exercise and Health PDF

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Nutrition for Exercise and Health...

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NUTRITION FOR EXERCISE AND HEALTH WHAT IS NUTRITION: - Science of food → sums total of all process involved in both the utilisation of food ● Indigestion - How do we take food in ● Digestion - Broken down and goes through digestive tract ● Absorption - nutrition absorbed out of food ● Metabolism - Used as an energy source, powering something within the body FUNCTION OF FOOD: - Provision of energy ● Sustain biological processes and functions - Promotion of growth and development ● Stunted growth caused by not having adequate nutrition - Regulation of metabolism ● Maintain core body temperature ● Wounds healing ● Heart beating - Protection of organs ● Mainly through fat CATEGORIES OF NUTRITION: Macro - nutrients - Larger quantities ( grams) → Essential food source ● Large quantities on a daily basis ● This consists of → Carbohydrates → Fats → Proteins ● Maintain organisms structural and functional integrity ● Fueling biological work - Provides energy during both rest and physical activity Micro - nutrients - Smaller quantities (micrograms) ● This consist of: → Vitamins → Minerals ● Facilitate the energy transfer ● Tissue synthesis - regulate anabolic and catabolic reactions ● Effective regulation of metabolic processes → Links to body maintaining homeostasis CARBOHYDRATE: - Simple Carbohydrates ● Monosaccharides - Basic carbohydrates (Single sugar molecules) → Glucose (Natural) → Fructose (Natural)

→ Galactose (Combines with glucose to produce lactose) ● Disaccharides - (Two sugar molecules) → Sucrose → Maltose → Lactose - Complex Carbohydrate ● Oligosaccharides - (Between 3 to 10 sugar molecules) → Maltotriose → Maltodextrn ● Polysaccharides - (Several hundred thousand sugar molecules) → From plants = starch → From animals = glycogen - Energy source - Stored as Glycogen - Converted to fat FUNCTIONS OF CARBOHYDRATES: - During exercise: ● Energy source - muscles contraction ● Protein sparer - keep protein in muscles ● Breaking down fat - glycogen depletion ;incomplete fat breakdown - ketone bodies → raise body fluid acidity ● Fuel for CNS - Brain needs Carbohydrate to function DIETARY FIBRE: - Edible parts of plants that are not broken down and absorbed by humans - Divided into water: ● Insoluble (eg. cellulose) ● Soluble (eg. pectin and inulin) - Improved luxation and protects against colon cancer ● Risk of CVD ● Risk of Type II diabetes - Improved weight management FUNCTIONS OF FIBRE: Insoluble fibres

Soluble fibres

- ↑ Satiety (bulky food) - ↓ Energy density of meals and rate of gastric emptying - influences the rate of micronutrient absorption - Stool regulating properties in the colon ● ↓ transit time through the intestines ● Promotes bowel regularity

- Properties to ↓ blood cholesterol concentrations and normaise BG - Highly fermentable: ● Promotes healthy gut flora and immune system.

FUNCTIONS OF DIETARY LIPIDS: - Fuel to most cells - protection of vital organs - fat soluble vitamins ( A,D,E & K)

- Hormones - cell membrane CHOLESTEROL: - Lipid found in animal cell membrane ● Maintains fluidity of membrane ● Aids in the metabolism of fat soluble vitamins (Eg. estrogen and vitamin D) ● Precursor for vitamin D synthesis & other steroid hormones - Lipoproteins ● Very low density lipoproteins (VLDLs) → Mostly lipids → Carries cholesterol to arteries from liver ● Low - density lipoproteins (LDLs) → Carries cholesterol to arteries from liver ● High density lipoproteins (HDLs) → Most protein and least lipids and cholesterol → Remove excess cholesterol from the arteries and carried to liver PROTEIN: Structure: - Proteins are chains of amino acids (300 AA) - 20 amino acids acids in human proteins ● 11 can be synthesised (non essential AA) ● 9 can not (essential AA) - RDA ● 0.8-1.2g/kg bw FUNCTIONS OF PROTEIN: - Synthesis of body protein - Structural parts of all cells ● Muscle, skin, hair ● Bones and teeth (minerals embedded in protein structure) - Synthesis of transport proteins, immune proteins - Synthesis metabolic mediators & other regulatory substances ● Neurotransmitter, hormones , DNA , RNA WATER: - Body contains - 60 to 70% water - Water intake typically 2-2.8 L/ day (=1.1.5L from fluid) - Produce water as a by product of ATP - Functions of Water ● Lubricating joints ● Maintaining body temp ● Carrying nutrients to cells via blood

Carbohydrate loading:

- Create a state where the body has excess carbohydrates readily available for a specific event.

DIETARY CARBOHYDRATE INTAKE AND ENDURANCE CAPACITY:

PERFORMANCE DECREMENT:

LEG GLUCOSE UPTAKE:...