sports science - option d(3)

3.1: Define the term Basal Metabolic Rate (BMR)

The lowest rate of body metabolism that can sustain life

3.2: State the components of daily energy expenditure

• Basal metabolic rate

• Thermic effects of physical activity: energy expenditure above the resting metabolic rate (RMR) to allow for physical activity

• Thermic effects of feedings: the increment in energy expenditure above RMR due to the energy cost of processing food for storage and use

3.3: Explain the relationship between energy expenditure and intake

• Energy input (calories in food) and energy output (calories expended in daily physical activity) affect one another

3.3: Explain the relationship between energy expenditure and intake - Weight Loss

• Reduce caloric intake below daily energy requirements

• Maintain normal caloric intake and increase energy expenditure (through additional physical activity above daily requirements)

• Decrease daily caloric intake and increase daily energy expenditure

3.3: Explain the relationship between energy expenditure and intake - Weight Gain

• Increase caloric intake above daily energy requirements

• Obesity can result is a long-term positive energy imbalance exists

3.4: Discuss the association between body composition and athlete performance - Fat Mass

• the greater the relative amount of body fat on an athlete (above optimal levels), the poorer their performance will be

• a small degree of athletes may benefit from increasing their fat mass

• e.g. sumo wrestlers

3.4: Discuss the association between body composition and athlete performance - Fat Free Mass

• increasing fat free mass is desirable to athletes that require strength, power and muscular endurance

• undesirable to athletes requiring cardiovascular endurance e.g. long jumper/pole vaulter

3.4: Discuss the association between body composition and athlete performance - Accuracy of Body Fat Measurements

• The use of laboratory-based measuring methods (hydrostatic weighing dual/energy-energy X ray absorptiometry (DXA)……) is costly and highly skilled but produces accurate results

3.5 Discuss dietary practices employed by athletes to manipulate body composition

• Reduced carbohydrate diet: reduction of glycemic load, decreased insulin secretion

• Low glycemic index foods and high-fibre based diets

• Diet pills