Energy and Physical Activity Flashcards
What is the role of carbohydrates?
This is the most important source of energy and includes starch, dietary fibre and sugar.
What are the 2 classifications for carbohydrates?
- Complex
- Simple
How many types of carbohydrates are there?
2
What are simple carbohydrates?
Simple carbohydrates are broken down quickly by the body to be used as energy. Simple carbohydrates are found naturally in foods such as fruits, milk, and milk products. They are also found in processed and refined sugars such as candy, table sugar, syrups, and soft drinks
What are complex carbohydrates?
Complex carbohydrates, found mostly in whole plant foods, maintain their natural fibre and fuel your body with the energy it needs. Examples include beans, oatmeal, 100% whole-wheat bread, quinoa, barley, potatoes, sweet potatoes, and many other plant foods.
What is the role of fats as a fuel source?
We need only a small amount of fat in our diet. Fats and oils belong to the chemical family known as lipids and are an important source of energy. They are a source of essential fatty acids, protect vital organs, and insulate us against extreme temperatures.
What are 3 types of fats?
- Saturated fats
- Monounsaturated fats
- Polyunsaturated fats
What are saturated fats?
Found in animal products (e.g. cheese).
- Builds up cholesterol
What are monounsaturated fats?
Avocado, nuts, olive oil. There is evidence to show it’s good for us.
What are polyunsaturated fats?
Fish, nuts, soybeans. Reduces cholesterol, it’s good for us and our hearts).
What is the role of proteins?
Helps with the growth and repair of muscles. Helps to fight disease and infections.
- Animal protein: fish
- Plant protein: lentils, tofu
What is the role of ATP?
The body uses the high-energy molecule called ATP (adenosine triphosphate) to supply the energy needed for physical activity. ATP consists of one molecule of adenosine, linked to 3 molecules of phosphate by high-energy bonds. When one of the high-energy bonds breaks, energy is released. This also means the ATP has now lost one of the phosphate molecules - it has now become ADP (adenosine diphosphate). ADP cannot be used to supply energy but remains in the body waiting to once again become ATP.
What are the 3 energy systems that the body uses to supply ATP?
- Alactacid system (sometimes called the ATP/PC system)
- Lactic acid system (sometimes called the anaerobic glycolysis system)
- Aerobic system (sometimes called aerobic glycolysis system)
ATP in the body:
The body stores a small amount of ATP in the muscles, ready if immediate movement is necessary. When the bond to a phosphate molecule breaks away it releases energy for this movement.
What is the role of the Alactacid System?
This system works to re-supply a phosphate molecule by splitting a compound called creatine phosphate. While this system is very efficient and quick, it lasts only 10-12 seconds as the body has a limited supply of creatine phosphate. Supplies of creatine phosphate can be stored in approximately 2 minutes.
What is the role of creatine phosphate in the alactacid system?
Creatine phosphate is one molecule of creatine and one molecule of phosphate. By splitting the compound, phosphate is made available to turn ADP back into ATP. ATP can then split to provide energy and the cycle continues.
What is the role Lactic Acid System?
When the body needs fuel for longer than 10 seconds and the supplies of creatine phosphate are diminishing, the lactic acid system can begin supplying ATP for activities lasting up to 2-3 minutes.
How does the Lactic Acid System function?
This system functions by breaking down carbohydrates to form glucose. Excess glucose is stored as glycogen in the muscles and liver. Glycogen breaks down to produce 2 ATP molecules and pyruvic acid. Without oxygen, the pyruvic acid becomes lactic acid. When this lactic acid builds up in the body it causes fatigue in the muscle.
