The Basics of Protein

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!?
So if we consider 9-10g of protein can be obtained from an ice cube size piece of meat. Have a steak, wack some salt on it and you've got a dish with lots of protein, good for your electrolyte balance and a bit of creatine, winning.

 Yours in sport,
- thesportscience



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