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IT IS THROUGH MANY YEARS of combined experience and having the unique privilege of working at the Sport Science Institute of South Africa that this book has evolved. We have worked with many general fitness enthusiasts, development, elite and Olympic athletes as well as international teams, and so have been able to develop a comprehensive hands-on nutritional approach, which integrates cutting-edge scientific principles that will help all individuals, regardless of their level of sport, to achieve their common goal – to perform at their best.

Sports nutrition is no longer a secret, based solely on anecdotal evidence. Before the 1960s, sports nutrition had evolved largely through self-experimentation, trial and error, and tradition, but with relatively few controlled studies. Sports nutrition is now a well-established science in its own right and it is well recognized that diet affects an athlete in many ways.

At the very basic level, good nutrition plays an important role in the maintenance of health, allowing the athlete to train and compete. Understandably an athlete needs to be healthy, and free of injury and illness to train adequately. Beyond health maintenance, nutrition can have a serious effect on performance through hydration, weight maintenance, and providing optimal fuel to train, compete and recover repeatedly.

Nutrition is a controllable factor that plays a role through the entire life of an individual; and for a world-class athlete proper nutrition can make the difference in winning, assuming that all other factors (genetic, behavioural, socio-economic, cultural and environmental) are equal.

Sportspersons are constantly bombarded with the latest sports nutrition fashions and trends. Too often, the magic offered by sports supplements diverts attention away from real performance enhancing and controllable factors like sports-specific nutrition matched to training regimes. It is a challenge to keep abreast and make practical sense of all this information, to separate the facts from the myths, and then to incorporate this into training and competition routines.

This book consolidates the scientific research in such a way that the athlete, the parent, the trainer, the clinician and dietitian are provided with practical and sport-specific nutrition game plans. Recommendations take into account the real life situations in which athletes find themselves and the foods that are most likely to be available to them. At times this means recommending the best choice of fast foods, for instance. To get the most out of this book, read part 1, which gives a good overview of sports nutrition and introduces new concepts such as fat-loading, the latest modified fluid guidelines, new issues around chronic fatigue, travel and jet lag, male eating disorders as well as the use and abuse of some of the latest supplements. Part 2 divides sports (ranging from golf, gymnastics, weightlifting, running, rowing, and team sports to extreme sports) into different chapters, depending on the features of each sport that affect nutrition requirements.

MEASUREMENTS

We tried to give quantities in user-friendly measurements. Amounts were rounded off to be more practical. Metric quantities were converted to measurements most commonly in use for that particular food. No conversions were given where the metric measurement is the international standard, for instance in scientific formulae and Olympic distances. The mathematical symbol ≈ is used to indicate the approximate equivalent.

NUTRIENTS

When we refer to a nutrient (carbohydrate, protein, fat or alcohol), it is always in g (grams).

Examples: 50g carbohydrate list

1.5–2g protein/kg body weight

500g carbohydrate per day

(Macronutrient requirement expressed as a percentage of daily intake can be misleading due to the wide range of requirements of athletes in different sports. It is also more practical and direct to give grams of nutrient per kilogram of body weight.)

ENERGY

Both kilojoules (kJ) and kilocalories (kcal) are provided.

1kcal = 4.82kJ, 1kJ = 0.2389kcal

When referring to the unspecified energy content of food or a person’s energy intake in general, we used the word ‘calories’, which seems to be understood worldwide. In this book the word ‘calories’ refers to kilocalories (kcal).

RECOMMENDED DIETARY ALLOWANCES

Dietary Reference Intakes (DRIs) consist of four different values: Estimated Average Requirements (EAR), Recommended Dietary Allowances (RDA), Adequate Intakes (AI), and Tolerable Upper Intake Levels (UL).

In the United Kingdom, however, Dietary Reference Values (DRV) are used. It is the generic term for Estimated Average Requirement (EAR), Reference Nutrient Intake (RNI) and Lower Reference Nutrient Intake (LRNI).

European Union regulations require Recommended Daily Amounts (RDAs) to be shown on food and supplement labels.

These recommendations are rough estimates and are always open to debate.

WEIGHT/HEIGHT

Kilograms (pounds) and metres (feet and inches)

1kg = 2.205 lb, 1m = 3.281ft

FOOD QUANTITIES (SOLIDS)

Household measures were chosen

250ml = 1 cup

25ml = 2tbsp

5ml = 1tsp

Ounces were chosen for smaller quantities, e.g. 90g (3 oz)

1g = 0,05327 oz

Pounds were chosen for larger quantities, e.g. 250g (½ lb)

1kg (1000g) = 2.205 lb

Other practical quantities were left as is e.g. 2 sports bars, 3 medium fruit.

FLUID QUANTITIES

Metric measurements have been converted into the measurement most commonly used for that particular fluid. Since most quantities are estimates and rounded off, we made no effort to distinguish between the UK and US measurements where these differ.

Water and sports drinks were converted to pints

(1 litre = 2.11 US pints or 1.76 UK pints)

Fruit juice to fluid ounces

(1 litre = 33.814 fl oz US and 35.195 fl oz UK)

Colddrink quantities were converted from ml to fl oz.

Quantities of milk, yoghurt and liquid meal replacement were converted to cups.

ALTITUDE

Metres to feet (1m = 3.281ft)

DISTANCE

Metres to yards (1m = 1.094yd), but note that Olympic distances were kept as standard.

SIZING IT UP

ONE SERVING	SIZE-WISE
90g (3 oz) red meat/poultry/fish	Deck of playing cards
Medium apple/pear 150g (5 oz)	Tennis ball
30g (1 oz) cheese	One matchbox
125ml (½ cup) of ice cream	Tennis ball
125ml (½ cup) of pasta/rice/vegetables	Tennis ball
30g (1 oz) or 2tbsp nuts/sweets	one handful
1 medium potato (90g; 3 oz)	Computer mouse
1 biscuit (15g; ½ oz)	A bath plug
250ml (1 cup) of cereal	A tight fist
5ml (1tsp) butter	A thumb tip
1 muffin/cinnamon bun/roll	A doorknob or fist
1 pancake or waffle	A CD