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Protein Supplements Welcome to the first monthly nutrition bulletin of the New Year. I’ve heard rumblings about whether golfers could benefit from taking a protein supplement so I thought this would be a good topic to start 2007! Protein, and its effect on performance and body composition, has interested athletes since ancient times when eating raw meat was thought to be beneficial for muscle gain. Many athletes today, particularly power and strength athletes, still believe that a high protein diet will enhance sporting performance. Such beliefs are further fuelled by the claims made by manufacturers of protein and amino acid supplements (amino acids are the building bricks of protein). Protein and muscle mass Muscle mass is determined by the training effect and not by excessive intakes of dietary protein. Protein is important – after all it is what muscle is made of – but it is training that stimulates protein synthesis. Strength is proportional to the crosssectional area of the muscle and this is related to increases in the diameter of the individual muscle fibres making up the muscle. As a result of training, there is an increase in amino acid transport into the muscle cells which enhances their incorporation in the muscle proteins. Not only does the muscle get stronger but the tendons get thicker and the bone gets stronger, particularly where the tendon joins the bone. All these adaptations are obviously vital if injury is to be avoided. Anabolic steroids often cause a mismatch as muscle increase is not matched by tendon increase and this can result in injuries where the tendon joins the bone. To gain muscle mass you need to increase the workload on your muscles by a well-planned training programme and eat a diet that contains not only protein but also adequate energy. Recent research seems to indicate that taking a “small” amount of protein before resistance training and having a carbohydrate and protein snack immediately after training can help to increase muscle mass and reduce post-exercise muscle protein breakdown as well as restore the carbohydrate or glycogen stores in the muscles. This would encourage rapid tissue repair and help to prevent muscle soreness developing. The amount of protein that is needed is small in relation to the amount of carbohydrate - of the order of 50g carbohydrate and 10g protein. This translates neatly into some very easy refuellers – * chicken, tuna, lean meat, ham or egg sandwich, * peanut butter baguette or roll * milkshake or smoothie made with milk and fruit * bowl of cereal and milk * baked beans on toast * scrambled or poached egg on toast Protein requirements Current general recommendations for protein intake, set at 0.75g protein per kg body weight per day, are based on a sedentary lifestyle and do not take into account the effects of taking regular exercise which will require an increase in protein intake. Current evidence suggests that strength or speed athletes (sprinters, rugby players etc) should consume about 1.7 - 1.8g protein per kg body weight per day and endurance athletes (marathon runners etc) about 1.2 - 1.4g protein per kg body weight per day. However it is unlikely that golfers even need to increase their intake to the level of endurance athletes. It certainly means that golfers should NOT be reaching for the nearest protein or amino acid supplement but instead should be ensuring that they include a wide variety of protein rich foods in their daily diet. If you are meeting your energy requirements (not losing weight and not gaining weight – unless of course you are actually trying to adjust your weight) you will almost certainly be consuming more protein than the estimated requirement. Just so you can check what your protein intake is here are portions that provide 20g of protein: Food - Weight of food - Portion of food Beef, lamb, pork - 75g - 2 medium slices Chicken - 75g - 1 small breast Fish - 100g - 1 medium fillet Fish fingers - 135g - 5 fingers Tuna in brine - 100g - 1 small can Prawns, boiled-no shell - 100g - approx 30 small prawns Semi/skimmed milk - 600ml - 1 pint Cheddar cheese (reduced fat) - 60g - 2 matchbox sized pieces Eggs - 3 size - 2 eggs Baked beans - 400g - 1 large can Lentils (cooked or canned) - 265g - 6½ tablespoons Nuts - 100g - 100g bag Seeds - 100g - 100g bag (6tbsps) Tofu, steamed - 250g The safest and simplest way to maintain an adequate protein intake is to eat a wide variety of foods. Many sources of vegetable protein (peas, beans, lentils and nuts) contain large amounts of carbohydrate, dietary fibre, vitamins and minerals as well as protein and these foods should be included perhaps more often than at present. Foods included in the diet primarily for their carbohydrate content also make significant contributions to the overall protein intake, not so much because they are a rich protein source but because they are eaten in such large amounts. For example, 4 slices of bread, 8 tablespoons of cooked pasta or 12 tablespoons of cooked rice will each provide 10g protein. Muscle growth (new muscle or muscle repair) is stimulated only in the presence of adequate amino acids so it makes sense to spread the intake of dietary protein throughout the day in order to maintain optimal blood amino acid levels. Not enough protein in the diet It is possible not to eat enough protein if you are seriously restricting your food intake to lose weight (body fat). Golfers who are fussy eaters may also be at risk of not eating enough. Poor protein intakes can lead to loss of muscle, slow recovery after exercise and if protein intakes are chronically low, serious health implications. However this is very, very unusual. Are protein supplements necessary? As energy intake increases to meet the extra energy costs of exercise, there is an automatic increase in protein intake too. A need for protein supplements is therefore extremely unlikely. One pint of milk will provide a similar amount of protein as a serving of protein supplement (most supplements are based on milk protein) at a much lower price. Protein for weight loss? Protein rich foods do seem to make you feel fuller and for longer than foods rich in carbohydrate or fat. I’m not talking about Atkins-type diets here but by increasing protein intake slightly and decreasing carbohydrate intake slightly and keeping fat intake low, you may find you can lose a little bit of weight. Aspects that led health professionals to be so anti-Atkins (and quite rightly) such as the effect on blood cholesterol levels, increased risk of kidney stones or loss of calcium from the bones do not seem to happen when the changes are only slight. Eating butter, cream, fat on meat etc and cutting back all carbohydrates to virtually nothing is definitely not the way to lose weight for anybody and certainly not top level golfers. Perhaps the simplest, safest and best advice is to make sure you have protein and sufficient carbohydrate (to keep up your energy levels) at breakfast, lunch and your evening meal. Jane Griffin Sports Dietitian and Nutrition Consultant