Burning Calories By Walking

BURNING CALORIES BY WALKING

2009

INTRODUCTION : WEIGHT AND HEALTH

The association between weight and health risk is moderated by the percentage and distribution of body fat . Studies that focus on change in weight or body composition , either alone or in addition to fitness typically measure body mass index (BMI , abdominal girth and /or percentage of body fat . Although evidence links each of these measures with mortality and morbidity , taken together they provide a more comprehensive pro of health risk . For example , there is a small gradual increase in morbidity and

mortality for BMI between 25 and 30 For BMI between 30 and 35 the risks increase more rapidly and above 35 they increase dramatically . These findings are the basis of the current definitions of overweight and obesity (overweight is defined as BMI 25-30 obesity class I is BMI between 30-35 , class II is 35-40 (Tan et al , 74 . However for an individual , BMI is insufficient for determining health risks , especially for people in the overweight category . This is because the metabolic effects of obesity are related to the amount , type and distribution of body fat . People who are at greatest risk from being overweight or obese are those with centrally distributed body fat (apple shape (Reaven , 422 . Central or visceral fat has unique metabolic characteristics that increase the risk for type 2 diabetes and heart disease . For this reason measures of abdominal girth and body fat are important corollaries to BMI

When changes in weight or body fat are the...