Each of the following foods provides ~ 10 g of protein. These foods have moderate to low fat contents and are rich in other nutrients.

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1 Background Proteins, made up of amino acids, are the major structural component of muscle and other body tissues. There are 20 amino acids, 8 of which cannot be made by the body and therefore must be included in the diet. Vegetable or plant proteins can be limiting in one or more essential amino acid and therefore, food sources need to be combined in such a way to ensure all amino acids are consumed. This is particularly relevant for people who avoid all animal proteins such as milk and eggs. Proteins also have important functional roles in the body, being used in the production of hormones, enzymes and haemoglobin. Therefore, an adequate dietary intake of protein is essential for growth and repair of body cells, optimal muscle function, transmission of nerve impulses and immunity. Protein can be used as energy but it is not the body s preferred energy source and is only utilised when the body s carbohydrate and fats stores are lacking. This can be detrimental to other processes in the body which require protein such as tissue maintenance, growth and repair, and immune function. Good Sources of Protein Each of the following foods provides ~ 10 g of protein. These foods have moderate to low fat contents and are rich in other nutrients. Animal Sources 2 small eggs 30 g (1.5 slices) reduced fat cheese 70 g cottage cheese 1 cup (250 ml) low-fat milk 35 g lean beef, lamb or pork (cooked weight) 40 g lean chicken (cooked weight) 50 g grilled fish 50 g canned tuna or salmon 200 g reduced fat yoghurt 150 g light fromage frais Plant Sources 4 slices (120 g) wholemeal bread 3 cups (90 g) wholegrain cereal 2 cups (330 g) cooked pasta 3 cups (400 g) cooked rice 3/4 cup (150 g) lentils/kidney beans 200 g baked beans 120 g tofu 60 g nuts or seeds 300 ml soy milk 100 g soy meat Limber Sports Performance - Nutrition Information 1

2 Do Athletes Need More Protein? Most well trained athletes require only marginally greater protein intakes than those of generally active people. For example, Endurance athletes in heavy training require extra protein to assist their body to repair and recovery after training and also to cover a small proportion of their energy costs. Athletes who are in early stages of strength training require more protein in this initial stage until their body adapts to the stress of resistance exercise. Adolescent athletes who are growing are another group which have additional protein requirements. Despite this, all athletes tend to have increased energy intakes allowing them to easily consume larger protein intakes than sedentary individuals. In fact, most athletes protein intakes are well in excess of the recommended requirements and thus there is little scientific justification for special high protein diets or protein supplements. Estimated Protein Requirements Group Protein Intake (g/kg/day) Sedentary men and women Elite male endurance athletes 1.6 Moderate-intensity endurance athletes (a) 1.2 Recreational endurance athletes (b) Football, power sports Resistance athletes (early training) Resistance athletes (steady state) Female athletes ~15% lower than male athletes (a) Exercising approximately four to five times per week for min (b) Exercising four to five times per week for 30 min at <55% VO2peak Special Cases of Inadequate Protein Intake While most athletes consume more protein than their requirements, some exceptions to this may include athletes on very low energy diets or those cutting out large numbers of food groups for example fussy eaters, those with extensive allergies or food intolerances, travelling athletes with restricted food supply and poorly constructed vegetarian diets. These athletes should consider consulting a dietician to avoid reductions performance such as strength and power losses. Limber Sports Performance - Nutrition Information 2

3 The Benefits of Post-Exercise Protein Intake Rather than focusing on the quantity of protein in an athlete s diet it is the timing of protein intake that is most crucial. Including protein in your meal immediately after exercise and in the following 24 hours, enhances muscle uptake and retention of amino acids. Importantly, the effect of post-exercise protein intake is exemplified when the protein is combined with carbohydrates. Therefore a snack or meal rich in protein and carbohydrates is the best choice following training for muscle repair, adaptation to training and refuelling for the next session. Snacks or Light Meals High in Protein & Carbohydrates Flavoured yoghurt/milk drinks Low fat fruit smoothies Liquid meal supplements (reputable brands eg Sustagen Sport) Sandwiches with lean meat, low fat cheese Breakfast cereal with low fat milk Sports bars Protein Supplements It s all the craze now days for athletes to have supplements before and after their workouts. The fact is, that with a balanced and varied diet athletes consume all the protein they need for proper muscle repair and recovery. Supplements are useful to have when a meal or snack is not conveniently available, but they are not necessary for seeing results from your workout. Remember that not only are supplements expensive but there is no justification for the large quantity of protein they provide and they usually contain little other nutrients and minimal carbohydrates which are also important for recovery. Two great, inexpensive supplements are Sustagen Sport and Skim Milk Powder 1/3 cup of either, added to a cup of milk can provide you with extra protein, calcium and also carbohydrates, without costing much at all! Limber Sports Performance - Nutrition Information 3

4 Will Increasing Protein Intake Help Me Lose Weight? High protein diets are currently very popular in the media, but they are often lacking in scientific research. It is not advised that athletes have a high protein and low carb diet as carbohydrates are essential for fuel when exercising as well as for the brain. If an athlete is attempting to decrease their energy intake they might consider increasing the protein intake slightly which can help reduce appetite. However, this will only be successful if low fat proteins are chosen. Overall, just simply increasing protein intake will not help you lose weight. Losing weight is the result of the right combination of diet and exercise. Can Excessive Protein Intake be Harmful? Daily protein intakes under 2 g/kg body mass in healthy individuals are unlikely to be harmful. The effects of higher intakes are uncertain. High protein diets can lead to increased excretion of calcium which would be a concern for athletes at risk of weakened bones, for instance, female athletes with low energy intakes not menstruating. High protein intakes are also known to accelerate pre-existing kidney disease. Excessive protein diets also tend to be expensive, especially with the use of protein supplements. High protein diets may also increase fluid needs, however the most common issue with high protein diets is that other valuable foods eg fruit, vegetables, carbohydrates and fibre are often being displaced in the diet. Limber Sports Performance - Nutrition Information 4

5 References AIS Sports Nutrition 2009, Protein, Australian Sports Commission ACT, Australia, < Burke & Deakin 2006, Clinical Sports Nutrition, 3rd edn, McGraw-Hill Australia Pty Ltd. Joint WHO/FAO/UNU Expert Consultation. Protein and amino acid requirements in human nutrition. World Health Organ Tech Rep Ser 2007; 935: Marsh, KA, Munn, EA & Baines, SK 2012, Protein and Vegetarian Diets, MJA Open, 1 Suppl 2: Limber Sports Performance - Nutrition Information 5