Nelson Physical Education Units 3 & 4
Test your knowledge solutions
Chapter 11
Nelson Physical Education
VCE Units 3 & 4
Test your knowledge solutions
Chapter 11: Training adaptations
Test your knowledge p. 283
1 a Muscular hypertrophy allows for increased storage of glycogen.
b Anaerobic glycolysis leads to the formation of lactic acid. Most people consider lactic acid to be an unwanted waste product. Once oxygen becomes available, or the exercise intensity decreases, some lactate is oxidized to form ATP (energy) and some is synthesised to glucose in the Cori cycle. This then becomes available for other muscles to use as a fuel/energy.
2 a Increased use of fats should theoretically allow exercise to continue for longer as more carbohydrates are ‘spared’ for later use.
b Aerobic conditioning increases the enzyme ‘glycogen synthase’, and this increases the ability to convert glucose to glycogen as well as storing it. Thus aerobic conditioning can potentially avert hypoglycaemia as a fatiguing factor.
c Blood glucose levels can be maintained during exercise by either eating glucose-rich foods (lollies) or drinking glucose-rich ‘sports’ drinks throughout the athletic performance.
3 a Aerobic exercise (walking, cycling, swimming, etc.) is often prescribed for cardiac patients as a means of improving the structural and functional capacity of the cardiovascular and respiratory systems. The exercise reduces cholesterol (increases HDLs), increases cardiac blood flow and capillarisation and maintains cardiac musculature. The aerobic exercise also reduces the risk of suffering another heart attack compared to patients who undertake no aerobic exercise.
b High intensity workouts should be avoided by people suffering heart conditions/problems because they lead to rapid increases in blood pressure and result in rapid elevated heart rate. Both of these factors place great loads on the heart. Resistance training can be undertaken by people suffering heart conditions/problems but it must be supervised and involve light resistances of the order of 30–50% of 1 RM.
4 a Aerobically trained athletes have a greater a-VO2 diff. because:
· they are are able to direct more blood to working muscles
· they have increased numbers of oxidative enzymes and mitochondria which are able to extract more oxygen at muscle sites
· they have increased haemoglobin and myoglobin levels and an associated increased oxygen transport capacity to working muscle cells.
b In response to anaerobic training, greater volumes of blood pass through the lungs (pulmonary capillaries), which results in a greater proportion of used air being replaced by fresh air at the alveoli. This leads to the alveoli being better ventilated and having higher oxygen pressure to drive more oxygen into the blood to travel to working muscles.
c The increase in the amount of oxygen extracted at the muscular level potentially allows greater energy to be obtained from the aerobic energy system.
5 a Fast-twitch ‘A’ fibres are partially aerobic. They have a fast contraction speed and well-developed capacity for both anaerobic and aerobic energy transfer. These fibres respond well to aerobic training and can take on ‘aerobic’ characteristics. As a result of aerobic training, Peta’s fast-twitch ‘A’ muscle fibres will increase in their ‘aerobic’ characteristics, such as increased mitochondria, increased oxidative enzymes, increased myoglobin, increased triglyceride stores, increased capillary density and increased glycogen synthase. These will better allow her to play the role of centre which relies more heavily on aerobic energy production, which will improve as these functions all increase.
b fibre characteristics that will improve in response to aerobic training:
· Increased mitochondria – increased aerobic metabolism of fats and carbohydrates
· Increased oxidative enzymes – improved ability to produce aerobic energy
· Increased myoglobin – greater stores of oxygen at muscles allowing for more ATP to be produced aerobically
· Increased triglyceride stores – improved fuel usage at low intensities and allows glycogen to be spared for higher intensity efforts
· Increased capillary density – greater supply of oxygen to working muscles
· Increased glycogen synthase – better able to convert glucose to glycogen to be stored for use in game
c Given that training adaptations are reversible, it is important that the hard work put into training and developing improvements does not ‘slip’. An off-season program of maintenance ensures that pre-season training will bring Peta back to competiton levels quicker than if more training effects had been reversed. A maintenance program is also likely to prove advantageous in terms of her immune system and may reduce the likelihood of injury and contribute to improved health and well-being.
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