Physiology, Health & Exercise Lesson 16 Weight control & obesity Effects of exercise on body composition & weight control
Weight Control & Obesity Includes: The problem of rising incidence of obesity in UK Possible causes of obesity Possible treatments of obesity Effect of exercise on body composition & weight control
What is obesity? A chronic disease characterised by excessively high body fat in relation to lean body tissue. Defined in England as having a BMI of >30kg/m2
What is the scale of the problem with obesity? Based on data from England: Year % males % females 1980 6 8 1997 17 20 Write a statement to describe this data
Scale of the problem In Scotland: 14% of men and 17% of women classed as obese Approx 20% of children are overweight 8% of boys and 7% of girls are obese
Health Risks associated with obesity Higher risk of developing: CVD- including CHD & high blood pressure Type 2 diabetes 80% of sufferers are obese Traditionally seen as a disease of over 40s now found in children as young as 13
Health Risks associated with obesity Higher risk of developing: Cancers of e.g. colon, breast (maybe also uterine & ovarian) Osteoarthritis (due to excess pressure on joints) Respiratory problems (due to excess weight over the lungs)
Health risks Other consequences: Time off work due to illness Reduced life expectancy Economic implications
Causes of obesity Complex & interrelated & include: Environmental Genetic Psychological Metabolic Dietary If constantly consume more calories than expend then will eventually become obese
Causes of obesity 2 reasons for steep rise in last 20 years: Decrease in physical activity both at work & leisure Energy dense (high fat) diet
Treatment of obesity Need to reduce energy intake & increase EE Weight loss more likely to be maintained if levels of physical activity are increased by permanent lifestyle changes
Effect of exercise on body composition & weight control Important that activity is regular & strenuous enough to make person breathe more heavily than usual E.g. brisk walking, jogging, swimming, dancing Experts (e.g. HEBS) suggest everyone should do up to 30 mins moderate-intensity exercise most days Remember max heart rate is 220-age
Effect of exercise on body composition & weight control Exercise increases/helps to: Energy output relative to input Fat loss Preserve lean tissue prevent obesity
Effect of exercise on body composition & weight control The impact of exercise on body composition decreases as the fat content decreases