Sports Nutrition Bible

[ono]

Carbohydrate Loading

For those that don't know, carbohydrate loading is a technique devised in the 1960's to increase the muscles' glycogen stores above normal levels. The idea behind it being...the more glycogen you have available, the longer and harder you can exercise. This is potentially advantageous in endurance events lasting longer than 90 minutes and events which involve multiple heats or several short matches.

It is unlikely to benefit you if your event lasts less than 90 minutes as muscle gylcogen depletion would not be a limiting factor to your performance.

It is believed that carbohydrate loading increases time to exhaustion by around 20% and improves performance by 2-3%.

The classical 6 day regimen involved 2 bouts of of glycogen depleting exercise seperated by 3 days of low carbohydrate intake and followed by 3 days of high carbohydrate intake and minimal exercise.

The theory behind this 2 phase regimen is that glycogen depletion stimulates the activity of glycogen synthetase, the key enzyme involved in glycogen storage...resulting in above normal levels of muscle gylcogen.


Drawbacks

Not only did it interfere with exercise tapering, but the low carbohydrate diets left the athletes feeling rather shitty - weak, tired etc...

Add that to the fact that a lot of athletes never ended up achieving above normal glycogen levels. So the object was defeated really.

The correct way

The carbohydrate depletion stage isn't really required. It does more damage than good generally. A better way of loading would be to taper training on 6 consecutive days while following a normal diet during the first 3, followed by a carbohydrate rich diet during the next 3. That would leave you going into competition with above normal levels of muscle glycogen.

A clever way

You can also reach the same state of glycogen saturation by following this protocal...

High levels of glycogen can be achieved by taking in 10g of carbohydrate/1kg of bodyweight over the course of a single day, following a 3 minute bout of high intensity exercise. The rate of glycogen storage is greatly increased after such a workout. The advantage of this regimen is that only 1 day is required instead of 6, and very little change to our usual programme needs to be made.

[ono]

That pretty much brings me to the end of the carbohydrate chapter...

Time to go over a summary of the key points.

• A carbohydrate intake of 5-7g / kg bodyweight / day is recommended for regular exercisers, and 7-10g / kg bodyweight / day is recommended during periods of intense training.

• The GI Index is a more useful way of categorising carbohydrates for athletes, than the traditional 'complex' versus 'simple' classification.

• The GI is a ranking of carbohydrate based on their immediate effect on blood glucose (blood sugar) levels. Carbohydrates with a high GI ratingproduce a rapid rise in blood sugar; those with a low GI rating produce a slow rise in blood sugar

• Pre-exercise meal should contain approx 2.5g carbohydrate / kg bodyweight and should be consumed 2-3 hours before exercise. Carbohydrate should be in the form of Low GI.

• For moderate-high intensity exercise lasting more than 60 minutes, consuming 30-60g of moderate or high GI carbohydrate (in solid or liquids) during exercise can help maintain exercise intensity for longer

• Glycogen recovery takes just over 20 hours but depends on the severity of glycogen depletion, extent of muscle damage and the amount, quality and timing of carbohydrate consumed.

• Replenishment is quicker than normal during the 6 hour post exercise window, although it tapers down and goes back to normal after the 6 hour period.

[ono]

Protein

Ok in this topic i'm going to try to cover the following...

• The role of protein in the body

• Essential and non-essential amino acids

• Complete and incomplete proteins

• Protein metabolism

• Protein requirements for athletes

• Working out your protein needs

• Meeting your protein needs

• What happens if you eat too much protein

• And anything else that comes up that i want to talk about. Hopefully i'll be able to dispell a few myths and give you a better idea of how to effectively fit protein into your diet.

[ono]

Protein and it's role in the body

The word protein means 'of primary importance' and is one of the essential food ingredients that plays a critical role in human metabolism

(metabolism: a term used to describe all biochemical reactions within an organsim - you for example)

Structure: Proteins are made up of long chains of amino acids; a group of organic compounds that contain carbon, hydrogen, nitrogen and sulphur...(yawn .....)

The chains are formed by single amino acids bonding together as a peptide bond. If two amino acids combine together the result is a dipeptide and if three amino acids combine together the result is a (you guessed it...)tripeptide. Chains of 4-10 amino acids result in a peptide chain and 10-2,000 or more are referred to as polypeptides.

A protein may consist of only one polypeptide chain, or several that are folded together. The order of the amino acids along with the chain determines the nature and action of the protein.

There are between 20 and 25 protein amino acids that have been identified and in combination these can form an infinite number of proteins in the body in just the same way as the 26 letters of the alphabet are able to make up hundreds of thousands of words.

to be continued...

[ono]

I'm hopefully going to crack on with this over the next few weeks. Sorry for the delay, i've been away from the board and been really busy with coursework.

[ono]

Aha you fwockers though i'd forget all about this thread. I've been reeally busy with my coursework.

Ok anyway...protein...

So what is Protein i hear you ask, and why the hell do i need it?

Protein makes up part of the structure of every single cell and tissue in your body. Muscle tissue, organs, tendons, skin, hair, nails. Protein is needed for the growth and formation of new tissue (not kleenex), for tissue repair (not kleenex, i need new material i think), for energy production. It's also required to make up the various enzymes that speed up chemical reactions in the body, as well as being required to make hormones. Protein also plays a part in in maintaining water balance in tissues, transporting nutrients in and out of cells, carrying o2 and regulating blood clotting.

You see, it's not just a powder afterall.

Like i said earlier

'Structure: Proteins are made up of long chains of amino acids; a group of organic compounds that contain carbon, hydrogen, nitrogen and sulphur...(yawn .....)

The chains are formed by single amino acids bonding together as a peptide bond. If two amino acids combine together the result is a dipeptide and if three amino acids combine together the result is a (you guessed it...)tripeptide. Chains of 4-10 amino acids result in a peptide chain and 10-2,000 or more are referred to as polypeptides.

A protein may consist of only one polypeptide chain, or several that are folded together. The order of the amino acids along with the chain determines the nature and action of the protein.

There are between 20 and 25 protein amino acids that have been identified and in combination these can form an infinite number of proteins in the body in just the same way as the 26 letters of the alphabet are able to make up hundreds of thousands of words.'

Basically that's how proteins are made up. This next bit might not help you with your training goals but it's a fun video to watch as it explains how your body manufactures proteins and how it decides what to do with them once they are complete. It's amazing.

Quick explanation...

DNA has the instructions for building every single protein in your body

The DNA is unwound (process is called transcription) to expose the genetic instructions to assemble the specific protein

A machine copies this instruction to form a molecule called messenger RNA (mRNA)

The mRNA pulls the genetic code out of the cell nucleus(where the DNA is) and takes it to a complex called a ribosome.

The process of translation now begins...

Inside the ribosome a molecular assembly line builds a specificly sequenced chain of amino acids. These amino acids are transported from other parts of the cell.

Their sequencial arrangement determines the type of protein manufactured

When the chain is finished it's moved and folded into a protein (the shape it's folded into depends on it's function). After it's folded into a protein it is released to travel to it's required location. It does this with the help of a shuttle.


Anyway...watch the video, it's amazing.

http://uk.youtube.com/watch?v=983lhh...eature=related

[Althugz]

Whoa, this stuff takes me back

Good advice been given here guys.

I'd personally be interested to hear more about polyols - Malitol, sorbitol etc They weren't about when I got my qualification in nutrition. (Or at least they weren't as used as they are today). I know they are an alcohol derivative but interested to know more about these interesting carbs.