info@idealtermpapers.com
Case Study Assessment
Endurance exercise presents considerable challenges to the major body systems, particularly when undertaken in high environmental temperatures. The athlete may take several different measures before and during endurance exercise to improve performance and to avoid untoward consequences. However, despite these precautions, the athlete may experience a variety of different problems ranging from unpleasant to life threatening.
1. When exercise is performed at >70%VO2max in a high ambient temperature ( = 35oC), ventilation (VE) is higher at any given workload than when it is performed in a moderate temperature of ?16oC.
i. What mechanisms might underlie this effect? On the basis of recent evidence, which is/are the more likely to
be important?
ii. On the basis of what is known of how different physiological mechanisms adapt in high environmental
temperatures (eg sweating, cutaneous vasodilatation), how might you expect exposure to a high ambient
temperature over 10 days or so, to affect the ventilatory response to exercise in an athlete who competes in
high ambient temperatures? Explain your answer. How would you test your proposals? Is the change you
propose likely to be an advantage or disadvantage to performance? Explain your answer.
2. When exercise is performed at >70%VO2max in a high ambient temperature with adequate hydration, muscle lactate accumulation and venous plasma lactate concentration have been shown to be higher than when exercise is performed at the same intensity in a moderate temperature.
i. On the basis of the available evidence, are these effects likely to be due to changes in the cardiovascular
response to exercise, or to changes in metabolism?
3. When exercise is performed at >70%VO2max in a high ambient temperature, but without adequate hydration, the cardiovascular response to exercise is compromised and fatigue occurs earlier. Typically the athlete shows a smaller increase in cardiac output, arterial blood pressure gradually falls and the increase in leg
muscle blood flow is reduced.
i. Discuss the reflex mechanisms that may contribute to these cardiovascular changes. What are the most likely
explanations for the earlier fatigue and which is most likely on the basis of current evidence?
4. At most marathon events, supplies of water and “sports” drinks are provided in intervals along the route. Some runners take the opportunity to drink at regular intervals, to avoid dehydration.
Others throw bottles of water to avoid overheating.
Measurements made at the end of such races have shown that a substantial number of runners had a plasma sodium level of <135mmol/L and in some, plasma sodium feel further after the race. Some of these runners had maintained body weight, or even gained body weight during the race. Nausea during and after the race was common; some vomited after the race; many complained of headache. i. On the basis of available evidence, what is the most likely explanation for the adverse changes during the event ie nausea, headache etc? How would the kidney deal with this situation? How many sympathetic and hormonal influences on renal function contribute to the outcome? ii. On the basis of published evidence, what is the most likely explanation for the further fall in plasma sodium after the race? 5. The traditional view has been that a high carbohydrate diet is the best preparation for endurance exercise so that intramuscular stores of glycogen are maximized. However more recently it has been argued that adding more fat to the diet can improve performance and limit fatigue, providing carbohydrate intake is maintained at 35-40% of total calories. i. If you were designing a study to test whether any improvement in performance on such a high fat diet were due to increased fat oxidation, what types of evidence could you look for and what measurements might you make? ii. How would you expect muscle fibre type and composition of the individual to affect fat oxidation during endurance exercise? 6. Athletes who have a complete spinal transection between thoracic levels 3 and 5 rely on their upper body musculature foe wheel chair endurance events. They have no motor control of muscles below the lesion and no sensory feedback from these regions to the brain. i. How would you expect the cardiac response (heart rate and stroke volume) to exercise at >70%VO2max in these athletes to differ from that of an able bodied athlete.
Use the available evidence to support your answer.
ii. On the basis of current evidence, how would you expect this level of spinal cord lesion to affect the ability of the athlete to maintain body temperature when the event takes place in high ambient temperatures?
Are you looking for a similar paper or any other quality academic essay? Then look no further. Our research paper writing service is what you require. Our team of experienced writers is on standby to deliver to you an original paper as per your specified instructions with zero plagiarism guaranteed. This is the perfect way you can prepare your own unique academic paper and score the grades you deserve.
[meteor_slideshow slideshow="slide2"]Use the order calculator below and get ordering with idealtermpapers.com now! Contact our live support team for any assistance or inquiry.
[order_calculator]
