Body composition The three main components of human body are muscles,bones and fat. Body composition measurements attempt to measure mass and relative amount of these components in individuals. Results for children and youth cant be compared with those of adult population as such.

Body size is determined by height and weight. Body build is the form or structure of the body. Muscularity (mesomorphy) Linearity (ectomorphy) Fatness (endomorphy) Fat mass Fat-free mass Body composition refers to the chemical composition of the body.

Body build

Theoretical model of adult population (Behnke) MaleFemale Age (y)20-24 Standing height (m) Body mass (kg) Fat (kg) Essential Storage F% Essential Storage Muscle (kg) Relative amount of muscle (%) Bone (kg) Relative amount of bone (%) Rest of body (kg) Relative amount of rest of body (%) Lean body mass (kg) Essential fat (kg) Essential fat (%) Muscles (kg) Muscles (%) Bones (kg) Bones (%)

BMI, Body Mass Index (kg/m 2 ):

Measurement of body mass attempts to tell if a person has too high or too low body mass. Changes in body mass dont indicate changes in the amount of body fat. Body mass relative to height (BMI) explains changes in body composition in for instance dieting

Approximation of fat location by waist:hip measurement High fat content of body is a health risk. Localization of body fat at certain places in body is an important factor for these risks. So called visceral fat (around internal organs) has been shown to be very detrimental for health: hypertension type II diabetes hyperlipidemy heart problems

Waist circumference of more than 100 cm for men and 90 cm for women is considered good indication of middle- body fatness. The relationship should be less than 0.95 for men and less than 0.86 fo women.

Fatfold measurements Body composition measurement done by subcutaneous fatfolds correlates well (r > 0.80) with hydrostatic weighing. Subcutaneous fat is in direct relationship with whole- body fat. Measurements differ by number and placement of fatfolds: - 4-pisteen menetelmä (Durnin & Rahaman, 1967) - 7-pisteen menetelmä (Jackson & Pollock, 1985)

d. Bioimpedance (BIA)

Lean body mass = Body weight – storage fat (Fat-free mass = Body weight – all fat) Skeleton weight = 3.02 * (H2 * F * R * 100) H = standing height F = right + left femurcondyle width R = right + left radioulnar width

Achieving Optimal Weight Combine proper diet with exercise. Lose no more than 0.5 to 1.0 kg (1 to 2 lb) per week. Reduce caloric intake by 200 to 500 kcal less than daily energy expenditure. Use moderate resistance and endurance training. Decrease fat mass and increase fat-free mass