1. Diabetes Mellitus and Osteoporosis

2. Diabetes Learning Outcomes
Explain the role of insulin and glucagon in the control of blood glucose levels;
State that non-insulin dependent diabetes mellitus (NIDDM) is generally associated with obesity;
Describe how cells become resistant to the effects of insulin in NIDDM;
Describe the effect of exercise on blood glucose levels in subjects with NIDDM.

3. Diabetes
Diabetes - failure to control blood glucose levels and impaired ability to store glucose
Normally tightly controlled by the opposing action of the hormones insulin and glucagon.
REMEMBER:
Glucose  Insulin Glycogen (in liver & skeletal muscles)
Glycogen  Glucagon  Glucose (in blood)
Feedback diagram

4. Diabetes
Insulin has different target cells, mainly skeletal muscle, liver and fat cells.
Insulin binds to specific receptors in the cell membrane of its target cells. Insulin- receptor complex allows uptake of glucose into the cell.
Insulin must be administered by injection.
Two types of diabetes.

5. Type 1 Insulin dependent diabetes mellitus (IDDM)
5-10% of cases
Rapid onset/progress
Caused by destruction of insulin producing β cells resulting in insufficient insulin production.
Commonly occurs in childhood and treatment involves regular insulin injections.

6. Type 2 – Non insulin dependent diabetes mellitus (NIDDM)
Much more common (90-95% of cases)
Typically develops later in life, mainly in overweight individuals
Tissues less sensitive/resistant to insulin
Targets cells have a deficiency in insulin receptors.

7. Type 2 – Non insulin dependent diabetes mellitus (NIDDM)
Pancreas tries to compensate but cells wear out and insulin production decreases leading to blood glucose and diabetes.
Becoming more common in children
Obesity appears to be the greatest risk factor
Treatment: Regular exercise, carefully controlled diet and sometimes insulin injections.

8. Diagnosing Diabetes
Excess glucose appears in urine and can be detected by Clinistix.
Glucose Tolerance Test: monitoring blood glucose levels of a fasted individual’s response to drinking a prescribed volume of glucose solution.

9. Exercise and Type 2 Diabetes
Insulin sensitivity is greater in physically fit individuals than unfit individuals.
It is thought exercise reduces insulin resistance by: adapting skeletal muscle (capillary network, blood flow and no. of insulin receptors) and increasing enzymes associated with glucose storage
Effects short-lived, exercise must be regular

10. Osteoporosis Learning Outcomes
Describe the cause of osteoporosis;
State that Osteoporosis affects men, women and children but is most common in post-menopausal women;
Describe the effects of exercise on bone mass and osteoporosis.

11. Osteoporosis
Bone is a living tissue which is constantly being broken down and laid down.
Bone formation>Bone breakdown = dense, strong bones.
Peak bone density yrs.
Osteoporosis long term condition where breakdown exceeds formation.
Osteoporosis

12. Osteoporosis High risk of fracture, loss of height, chronic back pain
Osteoporosis can affect men, women and children but is most common in menopausal women.

13. Risk factors for osteoporosis
Age – peak bone density yrs
Sex – men have denser bones and lose bone at a slower rate
Menopause – oestrogen promotes absorption of calcium from the diet.
Diet – insufficient calcium and vitamin D
Family history
Smoking and Excessive alcohol
Insufficient or excessive exercise

14. Exercise and Osteoporosis
Bone strength is increased by weight bearing exercise.
Exercise also strengthens tendons, ligaments and points of attachment.
Regular exercise is essential for development and maintenance of health bones
You must maximise bone density before the age related losses occur

15. Treatment of Osteoporosis
There is no cure.
Preventative measures essential
Regular weight bearing exercise and resistance training
Maximise bone density
Diet rich in calcium and vitamin D
(Hormone replacement therapy)

16. Typical Essay Questions
Outline the role of hormones in the control of blood glucose levels. Discuss the effects of exercise on diabetes (15 marks).
Discuss the effects of exercise on weight control and on bone composition (15 marks).
Discuss the role of exercise in the prevention of: (i) obesity (ii) osteoporosis and (iii) diabetes mellitus (15 marks).

17. Websites http://www.diabetes.org.uk/home.htm