BODY COMPOSITION

WHAT IS BODY COMPOSITION?How the body is made up. Split into 2

components.

Fat mass refers to a persons percentage of body weight stored as fat (within adipose tissue)

Lean body mass, weight of the rest of the body (bones, muscles, organs, tissue)

Height and weight are not always a good indicator of body composition

AVERAGE PERCENTAGE FAT MASS

Sport Male % Female %

Baseball 12-15 12-18

Basketball 6-12 20-27

Cycling 5-15 15-20

Field Hockey 8-15 12-18

Rowing 6-14 12-18

Swimming 9-12 14-24

Track – Runner 8-10 12-20

Track – Jumper 7-12 10-18

Track – Thrower 14-20 20-28

Triathlon 5-12 10-15

Volleyball 11-14 10-15

SIZE IN RELATION TO SPORT

Every sport has an ideal size for their requirement e.g. Compare high jump to sumo what are the needs of the competitors?

Weight is not that important its body composition that an athlete will be concerned about

Muscles weighs around 3 times more than fat so being heavier may not be a detriment

BODY MASS ASSESSMENT

Hydrostatic Weighing Athlete submerged in water Difference between dry and wet weight

gives percentage fat Fat is less dense and floats in water Most common and accepted method Most accurate but least available

method Only estimated density of fat which

varies to age, gender, race

BODY MASS ASSESSMENT

Bioelectrical Impendence Spectroscopy (BSI)

Low safe electrical current passed through body on body fat scales

Fat gives resistance to current (impedance)

Results set against height and weight chart, scales then give % fat

Measurement is affected by hydration It uses estimates of population so not

appropriate for elite athletes with more lean muscles tissue

BODY MASS ASSESSMENT

Skinfold measurement Skinfold callipers measure in mm the

level of fat below skin from selected body sites

Sum of these measurements estimates fat %

Locations vary but usually, tricep, bicep, subscapular and suprailliac

Most widely used as cheap Lots of measurements so accurate Testers need to be trained and measure

specific sites

SKINFOLD CALLIPERSSITE METHOD PICTURE

TRICEP Take a vertical skinfold parallel to upper arm, halfway between the shoulder and the elbow

SUBSCAPULA Take a diagonal skinfold across the back, just below the shoulder blade

BICEP Take a vertical skinfold halfway between the elbow and the top of the shoulder on the front of the upper arm

SUPRAILIAC Take a diagonal skinfold along the line of the iliac crest just above the hip bone

BODY MASS INDEX (BMI) Measure of weight against height Weight in Kg’s / Height in Metres

Squared Men range 20.1-25.0 Women range

18.5-23.8 Does not directly measure fat but is

correlated to body composition Better estimate to overweight/obesity

than other methods Not suitable, for young, elderly,

pregnant or athletes Athletes heavy muscles mean this is

disproportionate Used a government standard test for

health

BMI SCALE

Below 18.5 Underweight 18.5-24.9 Normal 25-29.9 Overweight 30-34.9 Obese 35+ Very obese

Calculate this BMI Weight 124 KGs Height 1.96 m

1.96 x 1.96 = 3.84 m2

124 / 3.84 = 32.3 BMI JONAH LOMU

OVERWEIGHT AND OBESITY

Occur as a result of an imbalance between energy intake and energy expenditure

If energy intake is greater than expenditure weight will increase

However increasing muscle mass will also will also increase weight!

ENERGY EXPENDITURE

Basal Metabolic Rate (BMR) The lowest amount of energy required for

minimum energy expenditure at normal rest levels (after 8hrs sleep and 12 hrs fasting)

Resting Metabolic Rate (RMR) Does not include the measure of sleep so is

generally used more frequently

AN AVERAGE DAY

60-75% is RMR 20-30 Physical activity Rest energy used when eating, absorbing

and digesting food (thermic effect)

Add all 3 to get Body's Total Metabolic Rate

ENEGY INTAKE

On average men 2550 calories, women 1940 per

day. Varies depending on? Lifestyle, age, height, weight, activity, body

composition.

A balanced diet looks like this (%’s) 10-15 protein No more than 30 fat 55-60 Carbohydrate

CALORIE INTAKE

Obviously the balance between energy intake and energy expenditure determines your total body weight

Balance of the 5 a day? Find these out

Depending on your diet calories can come from proportionally the 3 energy fuels, carbs, fats, proteins

HEALTH IMPLICATIONS

Diabetes Cancer Cardio-vascular disease Joint stress psychological harm Under performance

INFO FOR EXTENDED QUESTIONS

Huge increase in past 10 years Britons amongst heaviest in Europe By 2050 60% men, 50% women clinically

obese Only 5% of children walk to school 80% 20

years ago Cost of obesity to UK society by 2050 £50

Billion Obesity causes 18 sick days per year

EFFECTS OF PHYS ACT. ON BODY COMP

Increase activity means increased number of calories burned

Increased calorie burn even when activity has stopped post-exercise

Increases lean body tissue which burns more calories

Exercise increases the mobilisation of fats as energy fuel

Therefore increase RMR when even at rest