Energy drinks

samg93 · Joined: 11 May 2008 Posts: 2 Location: Edinburgh

i like to have a energy drink on a long ride. the energy drinks out there are just to expensive and taste like crap. Does any one no a decent east-to-make recipe? I remember there was one in MTB-UK but I think I through it out.

thank out:D

Gunner · Posted: Mon May 12, 2008 6:14 pm Post subject:

Sorry Sam, I don't have any recipes but maybe this is worth reading, it will give pointers to what's needed in a drink and does suggest a few recipes towards the end, depending on what type of drink you are looking for .....

Wink

""Depletion of the body's carbohydrate stores and dehydration are two factors that will limit prolonged exercise.
Dehydration

Sweating is the way in which the body maintains its core temperature at 37 degrees centigrade. This results in the loss of body fluid and electrolytes (minerals such as chloride, calcium, magnesium, sodium and potassium) and if unchecked will lead to dehydration and eventually circulatory collapse and heat stroke. The effect of fluid loss on the body is as follows:
% body weight lost as sweat Physiological Effect
2% Impaired performance
4% Capacity for muscular work declines
5% Heat exhaustion
7% Hallucinations
10% Circulatory collapse and heat stroke

Reference: "The Maintenance of Fluid Balance during Exercise", International Journal of Sports Medicine, vol. 15(3), pp. 122-125, 1994

Electrolytes

Electrolytes serve three general functions in the body:

* many are essential minerals
* they control osmosis of water between body compartments
* they help maintain the acid-base balance required for normal cellular activities

The sweat that evaporates from the skin contains a variety of electrolytes. The electrolyte composition of sweat is variable but comprises of the following components:

* Sodium
* Potassium
* Calcium
* Magnesium
* Chloride
* Bicarbonate
* Phosphate
* Sulphate

A litre of sweat typically contains 0.02g Calcium, 0.05g Magnesium, 1.15g Sodium, 0.23g Potassium and 1.48g Chloride. This composition will vary from person to person.
Glucose

Carbohydrate is stored as glucose in the liver and muscles and is the most efficient source of energy as it requires less oxygen to be burnt than either protein or fat. The normal body stores of carbohydrate in a typical athlete are:

* 70kg male athlete - Liver glycogen 90g and muscle glycogen 400g
* 60kg female athlete - Liver glycogen 70g and muscle glycogen 300g.

During hard exercise, carbohydrate can be depleted at a rate of 3-4 grams per minute. If this is sustained for 2 hours or more, a very large fraction of the total body carbohydrate stores will be exhausted and if not checked will result in reduced performance. Recovery of the muscle and liver glycogen stores after exercise will normally require 24-48 hours for complete recovery.

During exercise, there is in an increased uptake of blood glucose by the muscles and to prevent blood glucose levels falling the liver produces glucose from the liver stores and lactate.

Consuming carbohydrate before, during and after exercise will help prevent blood glucose levels falling too low and help maintain the body's glycogen stores. Many athletes cannot consume food before or during exercise and therefore a formulated drink that will provide carbohydrate is required.
Rehydration
Fluid absorption

Two main factors affect the speed at which fluid from a drink gets into the body:

* the speed at which it is emptied from the stomach
* the rate at which it is absorbed through the walls of the small intestine

The higher the carbohydrate levels in a drink the slower the rate of stomach emptying. Isotonic drinks with a carbohydrate level of between 6 and 8% are emptied from the stomach at a rate similar to water. Electrolytes, especially sodium and potassium, in a drink will reduce urine output, enable the fluid to empty quickly from the stomach, promote absorption from the intestine and encourage fluid retention.

Reference: "The Effect of Different Forms of Fluid Provision on Exercise Performance", International Journal of Sports Medicine, vol. 14, p. 298, 1993)

What's wrong with water?

Drinking plain water causes bloating, suppresses thirst and thus further drinking. A poor choice where high fluid intake is required. Water contains no carbohydrate or electrolytes.
Calculating personal fluid needs

During an endurance event, you should drink just enough to be sure you lose no more than 2% of pre-race weight. This can be achieved in the following way:

* Record your naked body weight immediately before and after a number of training sessions, along with details of distance/duration, clothing and weather conditions
* Add the amount of fluid taken during the session to the amount of weight lost - 1 kilogram (kg) is roughly equivalent to 1 litre of fluid
* After a few weeks you should begin to see some patterns emerging and can calculate your sweat rate per hour
* Once you know what your sweat losses are likely to be in any given set of environmental conditions, you can plan your drinking strategy for any particular event

Sports Drinks

There are three types of sports drink all of which contain various levels of fluid, electrolytes and carbohydrate.
Type Content
Isotonic Fluid, electrolytes and 6 to 8% carbohydrate
Hypotonic Fluids, electrolytes and a low level of carbohydrate
Hypertonic High level of carbohydrate

The osmolality of a fluid is a measure of the number of particles in a solution. In a drink, these particles will comprise of carbohydrate, electrolytes, sweeteners and preservatives. In blood plasma the particles will comprise of sodium, proteins and glucose. Blood has an osmolality of 280 to 330mOsm/kg. Drinks with an osmolality of 270 to 330mOsm/kg are said to be in balance with the body's fluid and are called Isotonic. Hypotonic fluids have fewer particles than blood and Hypertonic have more particles than blood.

Consuming fluids with a low osmolality, e.g. water, results in a fall in the blood plasma osmolality and reduces the drive to drink well before sufficient fluid has been consumed to replace losses.
Which is most suitable?

Isotonic - quickly replaces fluids lost by sweating and supplies a boost of carbohydrate. This drink is the choice for most athletes - middle and long distance running or team sports. Glucose is the body's preferred source of energy therefore it may be appropriate to consume Isotonic drinks where the carbohydrate source is glucose in a concentration of 6% to 8% - e.g. High Five, SiS Go, Boots Isotonic, Lucozade Sport.

Hypotonic - quickly replaces fluids lost by sweating. Suitable for athletes who need fluid without the boost of carbohydrate e.g. jockeys and gymnasts.

Hypertonic - used to supplement daily carbohydrate intake normally after exercise to top up muscle glycogen stores. In ultra distance events, high levels of energy are required and Hypertonic drinks can be taken during exercise to meet the energy requirements. If used during exercise Hypertonic drinks need to be used in conjunction with Isotonic drinks to replace fluids.
Want to make your own?

Isotonic - 200ml of orange squash (concentrated orange), 1 litre of water and a pinch of salt (1g). Mix all the ingredients together and keep chilled

Hypotonic - 100ml of orange squash (concentrated orange), 1 litre of water and a pinch of salt (1g). Mix all the ingredients together and keep chilled.

Hypertonic - 400ml of orange squash (concentrated orange), 1 litre of water and a pinch of salt (1g). Mix all the ingredients together and keep chilled."

Hope that helps Smile

It was taken from this excellent reference site:

http://www.brianmac.co.uk/drinks.htm

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