Protein is made up of 20 amino acids, of these
20, 11 are non-essential and 9 essential/indispensable. The 9 indispensable
cannot be produced by the body and can only be made by the consumption of
certain foods (hence the name 'essential'). The protein we eat is broken down
into amino acid form by the gut or gastrointestinal system.
In the muscle, the main amino acids are branch
chain amino acids which are oxidised for energy. They also play a huge part in
muscle building because Leucine (which is part of the chain) stimulates muscle
growth. Amino acids in the muscle contain nitrogen; nitrogen is great at
‘building things’ hence amino acids were given the nickname 'the building
blocks of protein'. However, when amino acids are broken down, nitrogen becomes
useless because it contains ammonia which is toxic to the body and must be
removed safely. Nitrogen is therefore removed by the liver and kidneys and
subsequently excreted as urea.
The body’s first source of energy is actually
carbohydrates, then fats and when these both run out it turns to amino acids. Protein contributes roughly 3-5% of your total energy expenditure, so where it is important to consume plenty of protein, carbohydrates and fats
are equally as important.
For this piece we are focussing on proteins,
not fats and carbohydrates so in terms of ‘how much protein should I be
eating?’, a sedentary person consumes roughly about 0.8 grams(g) of protein per
kilogram(kg) of body weight per day so,
a 60kg person should consume 48g of protein daily (60*0.8). However, an elite
endurance athlete or a weight lifter should roughly be intaking 1.6-1.8g of
protein per kilogram of body weight per day. Which means that same 60kg
person needs between 96 and 108 grams of protein daily!
Protein
requirements are always recommended to be 30% of your daily diet, sedentary or active but, where an active person
will increase their protein intake, they will also increase fat and
carbohydrate intake, keeping protein at the 30% threshold (Carbohydrates 45% and fats 25% respectively).
As stated earlier, an endurance athlete will
need the same amount of protein as a weightlifter. Despite many misconceptions!
Why? The reason is simple: endurance athletes have a higher workload and a
higher energy expenditure and so they burn carbohydrates and fat quickly and
move on to protein quicker as a result.
What about too much protein? Many people
think, drinking protein shakes before and after the gym will give them the
desired effects. If you're not putting the work in and you're not using the
protein up, the nitrogen will be stripped away by the kidneys and the rest
stored as fat. Side effects of excessive protein include: high calorie gain and
dehydration... And who wants that, really!?



No comments :
Post a Comment