sports science - option d(5)

5.1: State the normal levels of blood glucose at rest

4.00mmol/L - 4.5mmol/L

5.2: Outline the causes of hypoglycemia and hyperglycemia - Hypoglycemia

Low blood glucose below the necessary level to support the body

Causes:

• Insufficient food intake

• Excessive exercise (e.g. marathon)

• High insulin level among diabetics

5.2: Outline the causes of hypoglycemia and hyperglycemia - Hyperglycemia

Excessively high levels of blood glucose

Occurs when the body does not have enough insulin

Causes:

• Infections (cold or flu)

• Low insulin level in diabetics

5.3: Explain the transportation of glucose across the cell membrane when at rest and during physical activity - Resting Conditions

Transport proteins: GLUT1

• During rest, most glucose enters cells via the GLUT 1 transporters.

5.3: Explain the transportation of glucose across the cell membrane when at rest and during physical activity - During Exercise

Transport proteins: GLUT1, GLUT4

• GLUT4 transporters are also stimulated, without insulin, during physical exercise as a result of other stimuli such as calcium ions

5.4: Outline the effect of training on an athlete's ability to take in glucose at the cellular level

Exercise increases the amount of GLUT4 transport protein in cells which, in turn, enables a higher rate of glucose uptake into the cell for use as fuel

Training appears to result in changes to the amount of GLUT4 in the skeletal muscle cells as part of the initial adaptive phase.

Training effects on GLUT4 are reversible when training ceases.