Sport Books Publisher1 Nutritional Requirements: Types and Sources of Nutrients

Sport Books Publisher2 Nutrition The science of food and how the body uses it in health and disease

Sport Books Publisher3 Essential Nutrients 1.Proteins 2.Fats 3.Carbohydrates 4.Vitamins 5.Minerals 6.Water In this context, ‘essential’ refers to nutrients that the body is unable to manufacture (or not in sufficient quantities) They must be obtained from the diet

Sport Books Publisher4 Essential Nutrients Necessary for energy Needed for the building and maintenance of tissues Relied upon for the regulation of body functions

Sport Books Publisher5 Energy-Providing Nutrients Three nutrients provide the body with energy: 1.Proteins 2.Fats 3.Carbohydrates

Sport Books Publisher6 Energy Measurements Energy is expressed in ‘kilocalories’ 1 kilocalorie = 1000 calories Kilocalorie = Calorie (note capital ‘C’) 1 kilocalorie = heat required to raise the temperature of 1kg of water 1°C An average person requires approximately 2000 kilocalories per day

Sport Books Publisher7 FATS 9 Cal/g ALCOHOL 7 Cal/g CARBOHYDRATES 4 Cal/g PROTEINS 4 Cal/g Calorie Densities of Various Energy Sources

Sport Books Publisher8 Proteins Found in every living cell Act as structural components for: 1.Muscles (actin & myosin) 2.Bones (collagen matrix surrounding bone) 3.Blood (haemoglobin & plasma) 4.Enzymes 5.Some hormones (messenger proteins – ex. Insulin, which regulates glucose metabolism) 6.Cell membranes (transport, shape, receptors)

Sport Books Publisher9 Proteins Composed of chains of amino acids Each amino acid is made different by it’s side chain 20 commonly recognized amino acids Nine essential amino acids (cannot be synthesized by your body) 1.Histidine 2.Isoleucine 3.Leucine 4.Lysine 5.Methionine 5.Phenylalanine 6.Threonine 7.Tryptophan 8.Valine

Sport Books Publisher10 Protein Individual sources of protein are ‘complete’ if they supply all nine essential amino acids Complete protein sources include animal products such as meat, cheese, fish, eggs, poultry and milk

Sport Books Publisher11 Protein ‘Incomplete’ protein sources include those foods that do not contain all nine essential amino acids Usually from plant sources such as grains, beans, peas, and nuts Still good sources of amino acids Foods must be combined to get all amino acids (rice and beans for example)

Sport Books Publisher12 Protein Protein should comprise 10-15% of total caloric intake Protein consumed in excess of needs is stored as fat Inadequate protein consumption can lead to muscle wasting