Body Composition and Nutrition

This part of the site is setup by Th.C. de Winter, MD Sports medicine, and has a lot of info on the relation between diets and body composition.

Optimal body weight and composition

An optimal body weight differs individually. Not every rugby player will have the same optimal weight. Estimation of this optimal body weight can be done by an easy calculation: body height (in cm.) minus 100 = ideal weight. A better and more precise way of estimation can be done while using the Quetelet index; this is body weight (kg.) divided by body height x body height (meter!), the result of this calculation should be between 20 and 23. Measurement of the skinfold thickness (body fat percentage) is the best way of examination the body composition. Reference values: < 30 year 15%, 31-39 years 17.5% and > 40 years 20%.

Examples: Player A 25 years of age: 170 cm, 80 kg and 30% fat percentage

Player B 29 years of age: 180 cm, 75 kg en 14% fat percentage

Conclusion: player A carries a higher total body weight and more ballast (i.e. fat tissue) which gives a lower aerobic condition and a lower agility.

Important function of nutrition

Food mainly exists out of carbohydrates, fat and protein. Each of them has its own specific function in the body. Carbohydrates can especially be found in rice, bread and potatoes. The main function of carbohydrates is carrying energy for body movement. Fat can be found in butter, cheese, chocolate and nuts while they are necessary as reserve energy and for building up cells and hormones. Protein occurs in meat and milk products and is important for muscle building. An optimal dietary division is 60% carbohydrates, 20 % fat and 20% protein. A regular way of eating gives the most optimal way of energy supply and the least storage of fat tissue.

Too much fat

Most Western European meals contain enough and protein. Most of the times too much fat are eaten and little carbohydrates. This surplus of fat is stored as fat tissues around the abdomen and can hardly be moved once arrived. You have to lessen food like french fries, pork meat, soft drinks, alcohol, candy, chocolate, pie and peanuts. Advisable are foods like lean beef, boiled fish, chicken or turkey, bread, buttered milk, water, coffee and tea without milk and sugar.

Energy needs

Daily energy needs by men is around 11.100 kJoule (2600 kcal). Being a referee in a rugby game demands extra energy: 30 kJoule (7 kcal) each kilogram of bodyweight each hour.

Example. Flanker 170 cm, 80 kg en 30% fat percentage

: 2600 kcal/day (11.100 kJoule/day)
: 742 kcal extra (3120 kJoule)
: 3342 kcal

Vitamins and minerals

A normal regular diet will fully take care of an adequate amount of vitamins and minerals. In case of doubt only take one multivitamin tablet once a day.

Protein and amino acids

Bodybuilders mainly take these. It's quite easy to take extra protein during a normal diet. A surplus of protein will be stored as fat. No positive effects of these supplements have been found on aerobic fitness or strength; besides these supplements are expensive, so don't use them.

Creatine

Creatine is in the highlights nowadays because of its positive effects on strength and explosive power. It's not on the IOC doping list. Look here for more information on using creatine.

Need for fluids

Beside adequate nutrition at least 1-2 liter of water is necessary to make sure that all body processes function smoothly. During a match water is lost by sweating. It is important to restore this loss of water by enough and regular drinking. Loss of water can go up to 1 liter each hour. This can easily be measured by estimation of your body weight before and after a match. Especially during hot weather each moment of rest during a game must be filled with drinking. Maybe a "mobile drink bottle - as used in marathon and triathlon training - is a solution for referees. This bottle is worn in a belt at the back. Thirst quenchers like Extran, AA drink, Gatorade or Sport Energy are preferable.

A very simple way of checking if you did not drink enough and are perhaps dehydrated is by checking your urine colour. For this, you can download an urine colour chart.

Some tips

Prefer whole wheat bread and avoid fatty cheese and meats.

In the next tables an optimal composed diet is shown as well as an overview of frequently eaten snacks, fast food and drinks meals. So it is easy to see how much extra and "unhealthy" (fatty) energy these foods contain.

Example dietary calculation

 

Energy
kJ

Carbohydrates
gram

Protein
gram

Fat
gram

Breakfast:
3 slices of bread with low fat margarine
1 x meats
2 x apple syrup
200 ml orange juice


930
230
120
285
310


43
0
1
16
17


9
0
3
1
1


2
6
2
0
0

In between:
1 x coffee
with coffee milk
with sugar
2 slices currant bread
with low fat margarine
1 banana


2
100
340
790
160
330


0
2
20
36
0
18


0
1
0
6
0
1


0
1
0
2
4
0

Lunch:
5 slices of bread
with low fat margarine
4 x meats
1 x cheese
2 x yogurt drink


1560
390
480
320
740


71
0
2
0
34


15
0
10
5
9


3
10
7
6
1

In between:
1 x coffee
with coffee milk
with sugar
2 slices currant bread
with low fat margarine
1 banana


2
100
340
790
160
330


0
2
20
36
0
18


0
1
0
6
0
1


0
1
0
2
4
0

Supper:
1 lean beef
1 x gravy (extra water)
1 big portion of vegetables
5 boiled potatoes
1 x vanilla custard
1 banana


1000
300
170
800
470
330


0
0
6
42
15
18


28
0
4
6
4
1


14
8
0
0
4
0

Total

11879

419

116

78

Percents

100%

68%

19%

13%

 

Example snacks/sweets/alcohol

Energy
kJ
Carbohydrates
gram
Protein
gram
Fat
gram

Snacks:
1 mini pizza
1 minced meat hot dog
1 fried rice ball
1 egg roll1 1 french fries
3 chicken sateh + sauce
1 shoarma


1218
840
1050
1092
1932
1176
1974


35
6
26
28
57
9
29


12
10
5
11
7
24
22


11
15
14
12
23
17
30

Candy:
1 candy bar
1 chocolate bar chocolate ice cream
100 gram liquorices
1 mars candy bar
1 mars ice cream


1008
1134
1092
1260
1008
714


0
2
20
36
0
18


0
1
0
6
0
1


11
22
15
0
9
10

Cookie:
1 almond pastry1 butter biscuit
1 sponge
1 piece of pie
1 piece of cheese cake
1 slice of gingerbread
1 treacle waffle
1 sultana


1176
672
420
1344
1092
210
546
231


26
17
22
44
31
12
20
11


5
2
2
6
6
1
1
1


17
10
1
13
13
0
5
1

Crisps etc:
1 spoon pistachio nuts
1 hand of normal crisps
1 spoon of cashew nuts


504
231
504


1
5
4


4
1
4


11
3
10

Soft drinks/Alcohol:
1 glass alcohol free beer
1 glass of beer
1 glass of white wine
1 glass of coca cola
1 glass of coca cola light


189
336
294
231
0


10
6
0
14
0


0
1
0
0
0


0
0
0
0
0

So: one rugby match for a player of 80 kg is comparable to: