Digestive system
Explain peristalsis including the locations where it occurs.
Peristalsis is a physical digestive process using wave-like contraction to propel bolus through the esophagus and chyme through the small intestines.
What is the difference between glucose and glycogen?
Very similar. Glucose is the sugar we ingest, glycogen is the sugar we store in the liver or muscles.
Provide 2 reasons why dietary fibre or roughage is essential to the digestive system.
- Prevents constipation
- Lowers cholesterol
- Helps control blood sugar levels
- Increases the feeling of being full
- Promotes regular bowel movement
What can athletes do to avoid dehydration?
- Drink water and hypotonic sports drinks prior to their event.
- Drink water and isotonic sports drinks during their event.
- Drink water and hypertonic sports drinks after their event.
- Drink 100-200ml every 15mins during.
Why are villi so significant to the digestive system?
Villi line's the wall of the small intestine increasing the surface area which will also increase the rate of absorption and digestion.
Describe the whole process of breaking down fats.
Bile attaches to the fat molecules from the gall bladder.
The pancreas releases pancreatic lipase which attaches to the bile and sats to break them down into glycerol and fatty acids.
Intestinal lipase is released by the small intestine walls to complete the same process for fats.
Provide 3 differences between saturated and unsaturated fats.
- Saturated are solid at room temperature whereas unsaturated are liquid.
- Saturated include animal-based products eg dairy and meat, unsaturated are derived from plants eg sunflower seeds, canola oil and avocado.
- Saturated are unhealthy and unsaturated are healthy.
Explain carbohydrate cycling.
Carbohydrate cycling is when an individual matches their carbohydrate intake to the energy expenditure. High carb days = high intensity and/or long duration of training. Whereas low carb days may be a rest day or where low-intensity training is completed.
How does carbohydrate loading benefit athletes?
Allows athletes to store glycogen which can be used for longer in competitions and also delays the onset of fatigue.
Name the 2 functions the pancreas has in assisting digestion.
- Produces digestive enzymes eg pancreatic lipase or pancreatic amylase
- Releases hormones eg insulin
Name the two structures in the pharynx and define their role in ensuring food and air get to the correct location.
Uvula - prevents food and liquid from going up the nasal cavity.
Epiglottis - covers the passage and prevents food and liquid from going into the lungs.
Name the two water-soluble vitamins and explain their role.
Vitamin B = helps release energy, promotes good vision, and functioning of nerves and aids in metabolism and digestion.
Vitamin C = immune support, protecting cells and keeping them healthy eg skin cells, blood cells, and bone cells.
Explain what cholesterol is and provide examples of 2 foods high in cholesterol.
Cholesterol is a waxy-fat like substance that builds up on the inside of arteries narrowing the passage which increases the risk of blood clots and heart disease.
High cholesterol foods include: red meat, full fat dairy, baked goods/sweets, friends foods, butter and palm oil.
Explain the impact of consuming high GI foods would have if consumed 60 mins prior to beginning a competitive game of netball. Would this benefit their performance?
High GI foods would cause a spike in their blood sugar levels as they are absorbed quickly. This would be beneficial if they were about to begin their warm-up as they would feel energised and motivated, however, it will likely be used up before the game because high GI foods are absorbed rapidly. They would also need to consume moderate and low duration foods to have sustained energy for the duration of the game.
What is the formula for calcuting BMR?
BMR = weight x 24nrs x 4.2 - male
BMR = weight x 24hrs x 3.8 - female
Why is the liver so important?
The liver produces bile and without it, we would not be able to break down fats.
It's also responsible for detoxing the body of any harmful substances eg alcohol and lactic acid
And lastly, it stored glycogen (excess glucose).
Name 4 functions of water in the body.
- Assisting in the flow of blood through the vessels.
- Eliminating byproducts and waste from the body
- Regulating body temperature
- Diluting toxic waste to prevent organ failure
- Maintaining cell health
- Avoiding dehydration
What are the BMI norms for someone within the normal weight range for males and females?
Male = 20.1-25
Female = 18.5 - 23.6
NSW Health (doesn't use gender to differentiate) Normal weight: BMI of 18.5 to 24.9
- Refuel with low and high GI foods to replenish glycogen stores.
- Repair with high-protein foods eg meats to begin cell regeneration ASAP
- Rehydrate with water and electrolytes
Provide 2 reasons why athletes consume a small amount of dietary fibre pre-event?
- To reduce fecal bulk
- Maximise water absorption
- Minimize gastrointestinal discomfort, flatulence and diarrhea.
Explain the role of gastrin.
Gastrin is a hormone released by the lining of the stomach which stimulates the release of gastric acid eg hydrochloric acid. This allows the stomach to break down protein at a faster rate. It also assists in the growth of new cells for the lining of the stomach.
Explain the role of phosphorus in the body and include 2 examples of foods that are high in it.
Phosphorus is needed for bone and teeth health, helps with the regulation of blood pressure, production of ATP, and nervous system transmission of nerve impulses. Dairy = milk, yogurt, and cheese. Seafood = salmon, tuna, and sardines. Also in meat, poultry, eggs, nuts, and whole grains but not in the same quantities.
Explain ketosis and why some people may want their body to go into ketosis.
Ketosis is a metabolic state that occurs when your body burns fat for energy instead of glucose because it is not avavaiable.
This is often linked to fasting and is used to reduce body fat.
It is perceived as a easier way to loose weight rather than eating healthy and exercising.
Explain how low sodium and potassium may impact performance. Include 1 food high in each mineral.
- Blood pressure regulation.
- Upset pH balance which impairs nerve and muscle functions.
- Impact the regulation of fluid and nutrients in and out of body cells.
Sodium: potato chips, processed meats, pies, nuggets, sausage rolls, sauces, spreads and other condiments.
Potassium: dried fruits, beans, lentils, avocados, bananas, spinach, broccoli, potatoes.
How does bile work?
Bile emulsifies/attaches to the droplets of fat along with the pancreatic or intestinal lipase to break down fats into glycerol or fatty acids. Without bile, we would not be able to break down fats