- What are sugars?
- What are the functions of sugars in sports?
- What are the types of simple sugars that exist?
- Sugars as an energy source for sports performance.
- How to apply the best nutritional strategy in competition?
Sugars or monosaccharides are the simplest type of carbohydrate, which is why they are also called simple sugars. They have the very important property that they do not hydrolyze or decompose into other simpler compounds.
This means that in their molecular form they are already ready to be used by the body. At the same time, when they are grouped, their combinations form the other complex carbohydrates, also known as carbohydrates.
Within the classification of sugars, two categories are accepted, hexoses and pentoses, referring to the number of carbon in their structure: hexoses have six carbons and pentoses have 5 carbons.
HEXOSES – Glucose, galactose, mannose, and fructose which is a KetoHexose.
PENTOSES – Ribose, Deoxyribose.
Within the group of hexoses, specifically aldohexoses, they have a very interesting property that makes them a subgroup called diastereisomers: changing position any of the carboxyl groups attached to their carbons can be transformed into one another.
That is, galactose, glucose, and mannose can be converted into one another in succession, just by switching sides of a carboxyl group.
Their linear structure in the isolated state changes to a three-dimensional form when dissolved in water and thanks to this they can become more complex sugars or carbohydrates.
It is important to know that sugars are a quick source of energy for the body and that they provide us with 4kcal per gram.
Glucose being the metabolic objective of practically all our biological reactions, it is clear:
- Energy function.
To obtain it, however, the carbohydrates that come from our diet or from the glycogen storage deposits (reserve carbohydrates) that we have in the muscles and liver must first be broken down.
This degradation or hydrolysis aims to obtain glucose molecules (H2C12O6). This will be the one that will become the main way to obtain energy, also known as GLYCOLYSIS. The ultimate goal of this metabolic pathway is to obtain ATP.
The simple sugars that we have listed in the first section have the particularity that when ingested, they raise blood glucose levels almost immediately.
This implies that an intake of simple sugars is ideal during sports practice, since in these circumstances the energy demand by the muscles will not allow sustained hyperglycemia to occur and will not require great use of the insulin hormone.
- Post training glycogen resynthesis.
The second function that we mention in this article has to do with the resynthesis of glycogen, the well-known need after any sports practice to ingest carbohydrates or sugars to "fill" again the deposits that have been emptied during the activity.
It is mainly a matter of not being in continuous energy debt with our body after training, as this can have adverse effects on our performance, not only in sports, but also in our daily lives.
- Promote functions of the hormone insulin.
Also clarify that from a physiological point of view, there are other very interesting metabolic pathways to train the contribution of extra energy to the Glycolysis pathway, and that in specific strategies our body is capable of performing and recovering without the need to ingest carbohydrates in a timely manner.
In general, we could divide them into sugars of origin or direct source natural, or other sweeteners refined industrially by man.
Those that form an integral part of food and not processed products are, as a general rule, natural. The fructose and glucose contained in fruits and vegetables are, without a doubt, essential for life and do not, in a generic way, have to be harmful at all.
Refined sugar is the pure extract of sugar, that is, sucrose. A disaccharide made up of two molecules, one of glucose and the other of fructose, from sugar cane or beets.
- White sugar, which contains 99.5% sucrose,
- Refined sugar, which makes it 99.8%,
- Brown sugar that crystallizes but is not refined,
- Blonde sugar is lighter than brown sugar and with more sucrose.
For its metabolization, the action of compounds such as thiamine, riboflavin, niacin or pantothenic acid is necessary. For this reason, eating refined sugar is less healthy than doing it naturally, in more complete foods such as fruit or milk.
The usual and frequent foods that contain the most sugar are: soluble cocoa, breakfast cereals, cookies, pastries, soft drinks, chocolate bars, white chocolate, dairy desserts, fried tomato, sauces such as kepchup, sweets and candies.
There are many foods that naturally contain sugar but are healthy and nutritious. For example honey, which is a natural product rich in antioxidants, or coconut sugar, with fiber, minerals and vitamins and with a lower glycemic index.
That is why coconut sugar, sports speaking, is one of the best options as long as it is strategically combined with more complex carbohydrates to use the best of both worlds: quick energy coming from natural sugar and the release of energy delivered progressively by the hydrolysis of carbohydrates of different chain lengths.
As we have seen, the main function of this macronutrient has to do with obtaining energy for our cells. But obviously it is not the only energy pathway available to our body, since evolutionarily we would not have prospered if we had always depended on the intake of energy foods continuously, since there have not always been full pantries, supermarkets, and food availability. immediate.
In order to continue to exist as a species, our physiology created other mechanisms to obtain energy in cases of famine or low availability of this energetic macronutrient.
Sugars intervene with different prevalence in all these energy pathways:
energy sources in sport:
- Use of stored ATP – very small reserves, will only last a few seconds.
- Circulating glucose – part of the circulating glucose is used in the first movements.
- Glycogen Hydrolysis – liver and muscle glycogen stores begin to be broken down into glucose, which passes into the blood and is used to obtain ATP.
- Replenishment of carbohydrates – the ingestion of gels or bars during sports activity is done to continue supplying glucose and storing glycogen so that processes 2 and 3 continue to occur.
- Utilization of other macronutrients – if you have trained, the body can supply energy through reserve fats and through these synthesize glucose or glycogen to be stored.
It is vitally important to understand that none of these energy pathways turn on or off at any time, they all produce energy at different times with different prevalence depending on ATP/time demands, or what is the same depending on the intensity of the exercise we perform.
As we have seen in the previous sections, sugars that are often highly criticized because they are of refined and non-natural origin, are very beneficial if used with the appropriate strategy.
One recommendation that it would be interesting for athletes to take into account is that the gels contain simple sugars of natural origin, such as coconut sugar, and the rest compound sugars or carbohydrates (see article) to avoid causing hyperglycemia and ups and downs in performance.
- Exercise intensity,
- Duration of the activity,
- Sports discipline,
- Optimal state of hydration – hypotonic drink,
- Individual tolerance of each subject,
- Types of gels or bars chosen - with a formulation adapted to our physiology,
- Among others.
The most accepted amounts according to sports nutrition are presented in ranges between 30 to 60 grams of carbohydrates per hour of physical activity, although there are athletes who have trained to have higher tolerances and others to need lower doses .
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