BI0005 - Lecture 20 - Benefits of exercise

• General observations 
•    - Adipose tissue in excess
•    - BMI is raised
•    - Net Energy intake (I.e. Energy intake is greater than expenditure.

• Adipose tissue = White and Brown

• White - fat storage as triglycerides (twice energy of carbohydrates and protein). Approx 15% (male) ~20% (female) body weight

• Brown - heat storage. Subcutaneous.

• Adipocytes can increase in size (hypertrophy) and number 2(hyperplasia), but adipogenesis is irreversible

• BMI = weight in kilograms divided by height^{2 i}n meters.

• 18.5 → 25 Kg/m² = normal , >30 Kg/m² = obese

• • Failure to control food intake
• • Eating excess : social vs psychogenic factors
• • Lack of exercise
• • Genetics

• • Appetite - a Desire to eat, feelings of hunger, Satiety
•     • Involves roles for :
•         • CNS ( hypothalamus)
•         • Environment (eg temperature)
•         • Psychological (eg pleasure)

• Psychogenic factors - anxiety? depression?

• Social factors - Eating habits? Culture?

• Eg the obesity gene - produces leptin

• Acts on hypothalamus to suppress appetite & increase energy expenditure

• During fasting levels are low so encouraged to eat and conserve energy

Regular physical activity reduces the decline in functional capacity associated with aging and disuse.

Low fitness is of greater relative risk of all-cause mortality than cigarette smoking.

Reduced death risk for individuals who participate in regular exercise

Lower risk of Myocardial Infarction with frequent vigorous exertion and aerobic fitness

Reduced obesity

Reduced vascular risk

Reduced inflammatory markers

Enhanced neuronal function

Reduced cognitive decline/ dementia