Achievement Standard 2.3 Demonstrate understanding of the application of biophysical principles to training for physical activity.
COMPONENTS OF FITNESS There are several ways that we can classify fitness because fitness is specific to the requirements of each individual. We usually think of ‘being fit’ as being aerobically fit, but does our Olympic Weightlifter or 100 meter sprinter need to be able to run a Marathon to be successful in their sport? No, therefore the requirements to succeed in their sports are very different. What does fitness mean to you. Write down what your definition of fitness is and how do you judge if you are fit or not?
We classify our Components Fitness into 2 categories Health –related fitness Skill-related fitness Health-related components directly affect our health and well being, while Skill-related components tend to affect our performance level in our chosen sports rather than our health.
Health –related fitness Cardio-respiratory Endurance Muscular Strength Muscular Endurance Flexibility Body Composition
Skill-related components Power Balance Co-ordination Speed Agility Reaction time
Fitness testing Endurance Muscular strength Muscular Endurance An understanding of these components is vital for sport. After analysing the requirements for your sport you can then tailor a programme that caters for those components. You would then test the fitness levels for the different components. Think of tests that would cover the following components Endurance Muscular strength Muscular Endurance Flexibility Power Agility Speed
ENERGY SYSTEMS Energy for muscular activity and other biological work comes from the breakdown of adenosine triphosphate (ATP). ATP loses one phosphate molecule and breaks down to Adenosine diphosphate (ADP). Energy is then released. ATP storage is limited. The body must regenerate its ATP as quickly as it is broken down. This regeneration connects the ADP and a Phosphate together again to create ATP again. There are three energy systems for this: ATP-PC system Lactic acid system Oxygen (or aerobic or alactacid) system
The ATP-CP System This is used for high intensity exercise for tasks of approx. 10-20 secs (eg. sprinter). This system uses a chemical fuel reserve, Creatine Phosphate, which is stored in the muscle. This process is anaerobic (meaning it does not require the use of oxygen for it to work). CP is broken down into Creatine and Phosphate and the energy released from the breakdown is used to combine ADP and Pi to produce ATP.
The Lactic Acid System This is used for high intensity exercise for tasks of approx. 30 secs-3 mins (eg. 400m runner). The lactic acid system uses the anaerobic breakdown of glycogen which occurs in the cell. Glycogen is the form that carbohydrate is stored in the body (in the liver and in muscles). This process does not require oxygen. Lactic acid build-up occurs during this phase. This causes fatigue.
The Aerobic System Used for low intensity exercise that is longer than 2 mins (eg. Marathon runner). The Aerobic system produces its energy by utilising oxygen. This system uses glucose from the muscles. If glucose runs out, fatty acids are used. Finally if fat stores are depleted, protein is used. The results are the regeneration of ATP molecules and the production of by-products - water and carbon dioxide.
Summary of Energy Systems ATP-CP System Lactic Acid System Aerobic System Anaerobic Anaerobic Aerobic Very rapid Rapid Slow Chemical: CP Food: glycogen Food: CHO, Fat, Protein Very limited ATP Limited ATP Unlimited ATP Muscular stores Lactic Acid causes No fatiguing limited fatigue by-products Explosive, sprint 30 sec to 3 min Endurance 100m 400m Marathon