Nutrition for Rugby

The science

Intro

1. In order to achieve a greater proportion of lean body mass to fat mass, calorific expenditure needs to match or exceed calorific intake.

2. Energy balance (EB) = energy intake (EI) – energy expenditure (EE))

3. Professional rugby players EI is about 4012.6 - 5015.76 Kcal/d (Lundy et al., 2006) – ours should be slightly lower because our EE will not be as high (3800ish on a training day – this isn’t allowing for anybody who is looking to lose weight).

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Carbohydrates (CHO)

• The primary fuels which are used to support muscle activity are derived from carbohydrate and lipid sources.
• Since body fat stores contain enough energy to fuel low intensity, long duration activity for several days, it is generally felt that the rate limiting fuel during any type of strenuous, sustained activity, such as rugby, is CHO.
• CHO contribution becomes greater as the intensity increases towards the end of a match or training session and also during intermittent moments of explosive power and speed. Strength and power is essential in rugby. These requirements call upon anaerobic conditions and glycogen (stored form of CHO) stores are used rapidly.
• Total stores of CHO are limited and often substantially lower than the requirements of many athletes (you guys) therefore CHO intake prior to, during and post exercise is imperative to maintain or enhance performance.

Consumption:

• Guidelines for CHO intake indicate that daily recovery or fuel needs for an athlete with a moderate exercise programme should be 5-7g/kg/day – therefore if you weigh 80kg you should be eating 400-560g of CHO a day.
• If lower this may be insufficient for adequate glycogen (stored form of CHO) stores and circulating blood glucose, considering rugby players average size and energy requirements involving large anaerobic power and strength components.
• A decrease in exercise energy output followed by a cessation of exercise will occur if inadequate glycogen stores result.
• Preferably, the majority of dietary carbohydrate should come from complex carbohydrates with a low to moderate glycaemic index (GI) – these release energy over a more sustained period of time rather than a quick burst of energy and then a plummet again. – Examples are bran cereals, muesli, oats, wholegrain bread, pasta, rice, potatoes, bananas.

Proteins

• For rugby, the protein requirement would be the amount necessary to increase muscle mass, strength and power but also endurance and therefore could increase the energy contribution of protein.
• Muscle growth can only occur if muscle protein synthesis (re-building) exceeds muscle protein breakdown.
• The protein target for the average person of around 12-15% total daily energy intake is easily achieved as long as diet is not restricted.  Insufficient protein availability may lead to impaired metabolism, decreased lean tissue recovery, and possibly a decreased synthesis of oxidative enzymes and mitochondria.
• Increasing protein intake beyond the recommended level is unlikely to result in additional increases in lean tissue because there is a limit to the rate at which protein tissue can be amassed.
• The timing of protein ingestion is important, for example a protein and CHO containing snack both before and immediately after resistance exercise can help maximise training adaptations by increasing the production of anabolic hormones, reducing protein breakdown and supplying amino acids for muscle building
• Lundy et al, (2006) suggests a protein intake of 1.6-2.0g/kg/day for male rugby players (2nd rowers and props, weighing 100kg should be eating about 180-200g of protein a day to increase muscle mass– must be doing high amounts of intense exercise with this though – Centres/Wings (80kg) should be eating about 144-160g)
• In order to consume 190 g protein per day, a rugby player weighing 100 kg needs to eat 949 g of chicken/lean red meat, or 1 kg fish, or 800 g cheese, or 38 eggs, 5.7 litres of milk, or nine cups of lentils per day. These are huge amounts of food (not advisable – unused protein turns to fat)
• Many of the foods containing protein are also very high in fat.  For example, an 800g steak fillet contains 16 - 24 teaspoons of fat (100g fat).

Fats (lipids)

• Fat intake for male rugby players should be about 25+/-5% of total energy intake.
• Low fat diets, in addition to compromising health, reduce IMTG (Intra-Muscular Triglyceride stores), and a certain quantity of dietary lipid may be crucial for supplying free fatty acids to exercising muscle, especially in the later stages of a rugby match where this energy reserve is crucial.
• It has been shown that athletes should get 25-30% of their energy from dietary fat to ensure rapid replenishment of IMTG following exercise. If this is insufficient it can affect subsequent exercise and may also apply to rugby players
• During moderate exercise both CHO and lipids are oxidised, as exercise duration increases so does lipid oxidation (the use of fats as fuel - energy)

Fluids

• A decrease in aerobic work is likely with less than 2% dehydration
• Fluid should be ingested regularly in an attempt to consume the maximal amount of fluids during exercise that can be tolerated without gastrointestinal discomfort up to a rate equal to that lost through sweating.  However this is not always practical for large sweat losses. Fluid should not be ingested at rates greater than the sweat loss as this can increase the chance of hyponatraemia which can be just as, if not more, critical than the effects of dehydration.
• Below et al (1995) found water ingestion of 1330 ml, during and post exercise, improved performance in a subsequent time trail.  Furthermore when a 6% CHO drink was given the effects were enhanced. Jentjens and Jeukendrup (2003) suggest using beverages containing 1.2 g/kg/hour CHO is sufficient to replace glycogen storage

Suggestions in more simple terms

Pre – exercise consumption

- Eat extra carbohydrate and drink plenty of fluid in the 24 hours before the game. This will give you the best chance of performing well.

- On the day of a match it is important to have a good breakfast with whole wheat bread, cereals, muesli with milk, fruit (apple and banana). So you have a good start of energy within your body, before starting the match

- Have your last meal 3-4 hours before the game (eg, cereal and toast, pasta and red sauce) and a light snack 1-2 hours before (eg. banana roll and sports drink).

- If you suffer from pre-game nerves or can't compete with a full stomach, try having nutritious drinks (eg. smoothies) or eat early and top up with small snacks or drinks closer to the game.

- Try to drink 400-600ml of fluid 60-90 minutes before starting exercise.

- Pre-exercise carbohydrate ingestion of 25g in a solution significantly increases endurance performance in trained individuals

During exercise consumption

- It is important to top up fluid levels and carbohydrate during a game to minimise fatigue and help concentration.

- Sip from a drinks bottle during breaks in play. Don't spit it out.  150ml-200ml every 15 mins in demanding conditions.  

- Drink some sports drinks (4-8% carbohydrate) in place of water as they top up carbohydrate and fluid.

- At half time, aim for 200-400mls of sports drink or water. Carbohydrate gels can give an added boost to energy.

Recovery/post-exercise consumption

• Poor recovery after the game can lead to decreased energy during the following week of training. It can also slow down repair of injury.
• Drinking and eating for recovery is important to play at your best.
• Drinking and eating carbohydrate rich foods and protein as soon as possible after the game will increase your rate of recovery.  For example, you could eat a banana sandwich, sports drink, or bread and mince (i.e. clubhouse).
• For every litre of fluid lost, you should consume 1.2-1.5L fluid to ensure sufficient re-hydration. 
• A recovery diet that is high in carbohydrate (~10 g kg–¹ body mass/day) will allow athletes to restore their exercise capacity on the following day.

Choice of Drink

Water – is fine if you are exercising for an hour or less.  Drink small amounts throughout the day.

Hypotonic – have a lower concentration of particles than normal blood concentrations.  Contain less energy than isotonic or hypertonic drinks, but may not produce the same gastrointestinal discomfort that some people experience with the other more concentrated drinks.  Examples of these are any diluted juices or sports drink containing less than 4g carbs per 100ml (tells you on the bottle)

Isotonic – most common sports drink (lucozade sport being an example).  They contain a similar concentration of particles to normal blood levels (4-8g carbs per 100ml).  Great for energy and electrolytes before, during and after exercise.  Also help increase carb intake during carbo-loading periods.

Hypertonic – more concentrated than blood levels (>9g carbs per 100ml) – Lucozade Energy I think is 16g per 100g.  These have slower absorption rates than both hypotonic and isotonic.  They may not provide salts (essential for rehydration).   These drinks are best for restocking after prolonged exercise and for carbo-loading.  Some fruit juices also fall in this category.

Eating tips

• Be high in energy. Eat 3 meals and regular snacks everyday
• Take on lots of complex carbohydrate rich foods eg. Muesli, wholemeal bread, grains, oats, rice, pasta, lentils, potato, some fruits, smoothies. These should form the basis for most meals and snacks.
• Go moderate in protein rich foods for example lean meat, chicken, fish, pulses (such as lentils), eggs, milk, nuts, seeds and low-fat dairy products. You don't need a lot of protein to "bulk up". The amount of energy you eat is more important.
• Go low in fat. Avoid too much margarine (or butter), fatty meats (red meats), high fat takeaways (all takeaways) and snacks, fried food and creamy sauces. 
• Eat fruit & vegetables. These are needed for preventing illness, building muscle and repairing injury.
• Minimal alcohol. This is not going to be read and taken seriously and I am no one to talk but alcohol can lead to poor recovery, slow repair of injury and contribute to excess weight.

Basically……….

• Include enough carbohydrates as primary energy force, with the emphasis on the correct carbohydrates (low GI) for sustained energy throughout the day.
• Include enough protein to help with muscle building (important for after gym and training sessions where the muscle have been broken down)
• Consume limited amounts of fats, especially animal fats and harmful trans-fatty acids – stick to fats from plants and fish: supply the essential fatty acids.

Some healthy switches

Higher GI                       Switch to………………… Lower GI

Crunchy style muesli                                                          sugar-free muesli

White bread                                                                        pitta bread

Baguette                                                                              sourdough bread

Over-ripe banana                                                              under/medium ripe bananas

Biscuits                                                                    oatcakes

Cakes                                                                                   fruit loaf    

Flavoured yoghurt                                                              plain yoghurt with fresh fruit

Ketchup                                                                            tomato salsa

Bagel                                                                                     Tortilla wrap

Baked potato                                                                       Sweetcorn

Healthy ‘sudden bursts’

Medium-GI Carbs

Ripe banana, kiwi fruit, pineapple, sultanas, plain biscuits

Caffeine

Coffee or tea.  Don’t have too much of them though – save it for a real need.

Iron-rich energy foods

Eating too little iron can leave you feeling exhausted, so try an eat an iron-rich food everyday.  For example, lean red meat, eggs, bran cereals, sardines, dried apricots and dark green leafy vegetables.