Exercise Biochemistry
(08PEB022)

June 2009

2 Hours

PART A: SHORT ANSWER QUESTIONS (allow 60 minutes for this section)
Answer all the questions in this section
50 marks are available for this section

1. Briefly state the role of the following proteins in skeletal muscle: (5 marks):
(a) myosin
(b) hexokinase
(c) lactate dehydrogenase
(d) carnitine acyl transferase
(e) creatine kinase
2. Explain why the contribution of anaerobic metabolism to energy supply increases with increasing exercise intensity. (5 marks).
3. Explain why adenine nucleotide loss occurs during very high intensity exercise. (5 marks).
4. Explain how some amino acids can be used as a fuel for exercise. (5 marks)
5. Describe the role of GLUT4 proteins in carbohydrate utilisation at rest and during exercise.
(5 marks)
6. List the major modifications to the metabolic response to exercise as a result of endurance training. (5 marks)
7. What supplements might an athlete use to improve performance in high intensity exercise that results in fatigue in about 1-10 minutes? Include a brief description of their metabolic role. (5 marks)
8. Describe the main factors responsible for the integration of fat and carbohydrate metabolism. How are these affected by changes in substrate availability? (5 marks)
9. Which three factors account for the measured individual variability in any physical performance phenotype? (2 marks)
10. Explain how one gene can produce several different proteins. (3 marks)

1

11. What is heritability, and why are twins studies used to research its influence on physical performance? (5 marks)

PART B: ESSAY QUESTIONS
Answer TWO of the following questions (allow 30 minutes per question)
50 marks are available for this section

1. Discuss the roles of hormones and cytokines in the regulation of the blood glucose concentration and the mobilization of fat for use as a fuel during exercise.
2. Explain how exercise and diet affect protein turnover in muscle.
3. Describe the function and regulation of pyruvate dehydrogenase (PDH) and discuss its role in metabolism during prolonged exercise
4. Describe the main elements of Eric Newsholme's "Central Fatigue" hypothesis. Include some reference to specific studies that support or refute this hypothesis.
5. Discuss how IGF-1 may regulate the hypertrophic response of skeletal muscle to resistance exercise. 2