Preparing the Body for
Sport
Frances Campbell
Exercise Physiologist
Science and Sport
 Physiology
Body
 Psychology
Mind
 Biomechanics
Internal and External Forces
Physiologists
 Nutrition
 Fitness Testing
 Research
 Supplements
 Injury Prevention
SPORTS NUTRITION
"The amount, composition and timing
of food intake can profoundly affect
sports performance"
IOC Consensus Conference on
Nutrition and Sports Performance
Around the world, athletes and coaches recognise that
nutrition plays a major role in achieving success in sport.
The benefits of eating well include:
•Optimal gains from the training program
•Enhanced recovery between workouts and events
•Achievement and maintenance of an ideal body weight and
physique
•A reduced risk of injury and illness
•Confidence in being well-prepared to face competition
•Consistency in achieving high level competition performances
UK Dietary intake
Values refer to % of energy intake
Healthy diet
Optimum diet for sport
Why is an athletes diet different?
 Energy
 Increased energy demands from increased activity
 Maintenance of energy balance must be assessed
 Weight loss
 Increased fluid intake
Food for Energy
Energy from the diet is stored as body fat or glycogen
(carbohydrate in muscles and liver) and can be broken
down to provide energy.
Glycogen is the main source of energy during short bursts
of activity and at the start of exercise.
There is only a small store of glycogen in the body, and as
exercise continues the store becomes depleted and the
body starts to use some fat to provide energy. Most people
have quite a large store of body fat.
People who are fitter use up their store of glycogen more
slowly, and tend to use their stores of body fat for fuel
more readily.
Carbohydrates to fuel your training!
 Preferred fuel for aerobic and
anaerobic energy systems
 Delay fatigue in exercise
lasting longer than 60 minutes
 Essential role in recovery
 Strength and power athletes
require approximately 57gms/Kg body weight for hard
training
 Endurance athletes 7-10gms/Kg
body weight
Carbohydrate
 Athletic performance
limited by CHO availability
 High intensity + long
duration sports
 High CHO diets maximize
glycogen stores + 
performance
 Requirements sugar/starch,
liquid/solid dependent on:
Timing + type of physical
activity
DIETARY CARBOHYDRATES AND
GLYCOGEN
Preparing for Sport
gut
blood
liver
glycogen
glucose
100 g
glycogen
300 g
muscle
Typical training day for an elite boxer
 Running/Cardio
30-60mins
 REST/MEAL
 Sparring/Boxing
3min rounds 30sec rest 10-15 rounds
 REST/MEAL
 Weight Training
2 muscle groups pre session 4 sets of 20 reps
per muscle group 180 reps per gym session
What about protein?
The body uses protein from the diet for growth and
repair of tissues – which is of great importance if you
suffer from strain/injury during training.
Does it help build muscles and aid recovery?
Protein can help build muscle in resistance sports such
as weight lifting but be warned excess protein is
turned into adipose tissue (fat!)
Protein
 Large Organic compounds made of amino acids
 Complex structure difficult to break down
 The body rarely uses protein as a source of fuel
 Protein often used as a food supplement to aid muscle
growth
 Proteins are an extremely important macromolecule
Protein
Fat
Fat
 Can be liquid or solid depending on structure
 Different kinds of fats.
Saturated
Unsaturated
Fatty acids (Omega 3,6,9)
 NOT ALL FATS ARE BAD – all about balance
Another approach to having “extra” glycogen – train your
body to use less
The alternative to maximizing the availability of CHO is to conserve CHO
by maximizing the capacity to oxidize fat. The essential theory underlying
this strategy is the reciprocal relationship between FAT and CHO in terms
of providing energy for exercise.
Glycogen
Triglyceride
Glucose
Pyruvate
Free Fatty Acid
Acetyl-CoA
Fatty Acyl CoA
TCA (Krebs) cycle
Exercise and Supplements
 Diet is important for all athletes
 Due to lifestyle and training programmes and energy
demands its not always possible to gain requirement
from foods
 Many athletes use food supplements
Types of Supplements






Carbohydrate shake, and bars
Protein shakes, and bars
Caffeine supplements
Energy drinks
Vitamin supplements
Iron + calcium supplements
Vitamin supplements
If you have a healthy balanced diet
then you should not need to use
vitamin supplements. However, if
you do take one pick a multivitamin/mineral supplement
providing no more than 100% RDA
(recommended daily allowance)
BUT … at what point
does the use of
supplements become
cheating ???
Athletic substance abuse
“The International Olympic Committee (IOC) published its
first list of banned doping classes in 1967, in which it
listed narcotic analgesics, sympathomimetic amines,
psychomotor stimulants, and miscellaneous central
nervous system stimulants. Since that time the list has
evolved and grown, with the incorporation of anabolic
steroids in 1974, blockers and diuretics in 1985, and
peptide hormones in 1989”.
Responsibility of athletes
 It is the responsibility of the athlete to understand their
rights and responsibilities and to be aware of what they
are putting in their body, despite whether there was an
intention to cheat or not
 Athletes should seek advice if they have any questions
or doubts about their responsibility, medication or
treatment.
 It's what's inside that counts
Caffeine’s Ergogenic Effect



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Increased mental alertness/concentration central nervous system stimulant
Elevated mood/ decreased fatigue
Enhanced catecholamine release
Improved muscular strength
Effect Depends on:
Individual caffeine status
Individual variability
Caffeine dosage and administration
 Illegal (>12ug/ml)
approx.. 5-6 cups of strong coffee or 4 vivarin for a 150 pound person
consumed 2-3 hours before performance
Alcohol
 Alcohol effects all cells in the body.
 Alcohol (ethyl alcohol, ethanol) is a drug, it can also
be classified as an energy source as it provides
energy, about 7 kcal per gram.
 “uneconomical” - more oxygen needed to metabolize
a gram of alcohol than a gram of carbohydrates or fat
 The effects of alcohol are dependant on the blood
alcohol concentration.
Alcohol
 Alcohol may influence both psychological and
physiological processes related to physical performance.
 Psychologically, alcohol may benefit performance by
increasing self-confidence, decreasing sensitivity to pain,
or removing psychological barriers to performance.
 However, the most prevalent use of alcohol in sports
competition is related to its ability to reduce excess
anxiety.
Anabolic Steroids
 Testosterone (must be injected or it will be
destroyed by digestive enzymes)
 Anabolic Androgenic Steroids (AAS)
synthetic drugs designed to mimic the effects of
testosterone; taken orally or injected
 Human Growth Hormone (anabolic)
used like steroids to increase muscle mass
 Beta Adrenergic Agents (Clenbuterol)
Athlete substance abuse
 IOC list of banned substances
Amphetamines
Reduce fatigue, improve alertness, improve reaction time,
increase aggression and competitiveness. May be used outside
of competition to improve training. Contained within
recreational drugs.
Release neurotransmitters such as noradrenalin, dopamine, and
serotonin
Found in over the counter medicines such as cold remedies and
decongestants.
Athlete substance abuse
β agonists
Potent bronchodilators and may, therefore, improve
performance in aerobic exercise
Commonly found in asthma inhalers
Allowed for medical reasons
6% of athletes at the 2000 Sydney Olympics
declared the use of β agonists.
Athlete substance abuse
Anabolic androgenic steroids
Anabolic androgenic steroids (AAS) are used to improve
strength by increasing lean body mass, decreasing body
fat, prolonging training by enhancing recovery time, and
increasing aggressiveness and energy cardiovascular,
cosmetic, hepatic, infections, reproductive, and
psychiatric.
Other inhibiting factors
 Sleep
Sleep is important for the body and the brain, helps recovery and
healing from the stress of exercise.
 Stress
Emotional stress effects performance be reducing commitment and
concentration levels particularly important in sports with high skill
factors.
 Injuries
Injuries reduce training intensities and effect performance. Injuries
can be a sign of over training or incorrect diet.
Questions