Option D Nutrition for sports, exercise, and health Flashcards
(42 cards)
Outline the features of the principles components of the digestive system.
Mouth: mechanical digestion and chemical digestion
Esophagus: peristalsis action (muscles contracting)
Stomach: rugae, lumen, mucus coating
Small Intestine: villi and microvilli increase the area for absorption
Large Intestine: water balance, vitamin absorption
Pancreas: production of enzymes
Liver: production of bile
Gall Bladder: storage of bile
Outline the two forms of digestion that take place inside the mouth.
Mechanical digestion involves teeth breaking up food.
Chemical digestion by salivary enzymes, like amylase, breaks down carbohydrates.
State the typical pH values found throughout the digestive system
Mouth: 5.5-7.5
Stomach: 1.0 to less than 4.0
Small Intestine: 6.0-8.0
Describe the function of enzymes in the context of macronutrient digestion.
Enzymes are catalysts, proteins that work optimally under specific conditions (temperature and pH).
Optimum Environment:
Specific pH and temperature for each enzyme.
Substrate-specificity (e.g., Pepsin in stomach pH 1-4).
Increase in Body Temperature:
Increases metabolic rate and digestive process rates.
Substrate-specific:
Pancreatic lipase breaks down fats.
What is the role of Enzymes in Macronutrient Digestion
Catalysts speed up digestion.
Enzymes break down macronutrients into small molecules for absorption.
Specific enzymes for each macronutrient (e.g., Lipase for fats).
Explain the need for enzymes in digestion
Allow digestion at body temperature for survival.
Specific for substrates, enabling independent digestion of molecules.
LISTS THE ENZYMES THAT ARE RESPONSIBLE FOR THE DIGESTION OF CARBS, LIPIDS, AND PROTEINS FROM THE MOUTH TO THE SMALL INTESTINE
CARBS: Salivary Amylase, Pancreatic amylase
LIPIDS: Pancreatic lipase
PROTEINS: Pepsin, Trypsin, Protease
Describe the absorption of glucose, amino acids, and fatty acids from the intestinal lumen to the capillary network
Before entering the capillary network or the lymphatic system
Glucose, fatty acids, and amino acids cross
Brush-border membrane
Pass through the cytosol of the absorptive cell
The basolateral membrane
State the reasons why humans cannot live WITHOUT water for a prolonged period of time.
- Basic substance for metabolic processes.
- Regulates body temperature.
- Enables transport of essential substances.
- Allows for nutrient and metabolic waste exchange.
State where extracellular fluid can be located throughout the body
- Eyes, Saliva, Gall Bladder, Glands.
Compare water distribution in trained and untrained individuals
- Fat in Adiposities: Untrained individuals have more fat storage cells with less water.
- Trained Individuals: More muscle, less fat, and higher body water percentage.
Compare and contrast water distribution in Olympic sprinters and inactive individuals:
-
Similarities:
- Water distribution in intra and extracellular spaces.
- The water content of tissues remains relatively constant.
- Muscle glycogen stored with water.
-
Differences:
- Sprinters have higher water content in plasma.
- Sprinters have lower adipose tissue percentage.
- Sprinters have higher muscle glycogen and muscle mass.
Explain that homeostasis involves monitoring levels of variables and correcting changes in levels by negative feedback mechanisms.
- Homeostasis maintains a stable internal environment.
- Sensors, controllers, and effectors regulate variables.
- Antagonistic mechanisms alternate to maintain equilibrium.
- Negative feedback inhibits actions that disrupt homeostasis.
Explain the roles of the loop of Henlé, medulla, collecting duct, and ADH in maintaining the water balance of the blood.
D.2.5 Roles of Loop of Henlé, Medulla, Collecting Duct, and ADH:
- ADH: Controls water and salt levels.
- Low fluid levels stimulate hypothalamus receptors.
- ADH released, increasing water permeability in kidneys.
Describe how the hydration status of athletes can be monitored.
- Urine Color: Indicates hydration levels.
- Urine Osmolarity: Measures particle concentration.
- Variation in Body Mass: Monitors changes.
- Hydrometer: Measures liquid density.
Explain why endurance athletes require a greater water intake.
- Increased energy expenditure requires more hydration.
- Excess heat is managed by sweat evaporation.
- Lack of sodium replenishment leads to hyponatremia.
- List the Effects of Hyponatremia:
Headaches, Weakness, Disorientation, Seizures, Coma, Death.
Discuss the regulation of electrolyte balance during acute and chronic exercise
- Electrolyte balance issues in endurance exercise.
- Profuse sweating leads to sodium loss.
- Too much water intake can dilute electrolytes.
- Dehydration induces ADH, promoting sodium retention.
Define the term basal metabolic rate (BMR)
the lowest rate of body metabolism that can sustain life
State the components of daily energy expenditure.
Basal Metabolic Rate (BMR).
Thermic Effect of Physical Activity.
Thermic Effect of Feeding (energy needed to process food).
Explain the relationship between energy expenditure and intake
Energy Intake = Energy Expenditure for Weight Maintenance.
Weight Loss: Energy Output > Energy Intake.
Weight Gain: Energy Output < Energy Intake.
Weight Maintenance: Energy Output = Energy Intake.
Discuss the association between body composition and athletic performance
- More mass requires more energy for movement.
- Athletic performance depends on sustaining power anaerobically and aerobically.
- Excess weight increases injury risk.
- Lower body fat is generally associated with improved endurance.
List the Importance of Fat:
Shock absorption, Heat Regulation, Buoyancy, Fuel Storage.
Discuss dietary practices employed by athletes to manipulate body composition
- Individualized nutrition plans for training and competition needs.
- Carbohydrates as the primary fuel for intense efforts.
- Adjusting Macros, Caloric Intake, Water Intake, and Supplements.
