How much time do I leave from food to training?

Very interesting article about a question that we ask ourselves very often.

The gastric digestion process requires a blood supply to that area. And the practice of physical exercise will require it towards the muscles put into action. On the other hand, prolonged fasting causes a decrease in energy stores (glycogen) at the muscle level. For this reason, under certain circumstances a compromise of blood supply in one or another area or lack of "fuel" at the muscular level can be caused.

The period of time after ingestion and physical exertion should not be so short that digestion is cut off (due to lack of sufficient blood “supply” the digestive process stops and causes discomfort, nausea and vomiting), nor so long as to that when exercising the muscles are without glycogen (this is going to be used little by little as time goes by). Therefore, to determine the duration of this period, it is necessary to assess: the type of exercise, the amount and content of the previous meal and the individual factors that affect digestion and exercise tolerance after ingestion:

• Exercise: physical activity will force an increase in blood flow to the working muscles. The more intensity, the more flow. Therefore, the intensity of the effort must be taken into account; but also sudden movements, changes in rhythm, etc .: the digestive impact produced when running is much greater than when cycling or swimming. The outside temperature will also have its influence, due to the requirements of extra blood to the periphery for the control of body temperature.
• La food: first influenced by the amount, but above all for the content in certain nutrients. Thus, the fats cause a delay in the gastric transit of the alimentos (cost more to digest) and therefore lengthen digestion. Certain combinations ofliments slow digestion, such as fats with protein. Legumes are slower to digest in the stomach than, for example, pasta and rice.
• But both factors are conditioned by the digestive capacity of each individual and their tolerance to effort after ingestion. There are subjects who digest the same food in two hours and others need four. But in addition, there are individuals who need to have a sensation of gastric emptiness when exerting themselves and others require a certain sensation of satiety.

Taking into account all the factors mentioned, it seems difficult to give a general recommendation. However it is possible to follow a few basic principles that can help make things a little clearer:

1.- Reduce the proportion of fat in the food, especially in the intake that precedes exercise. Combine carbohydrates in moderate quantity, with also moderate proteins and reduce fats to a minimum (especially of animal origin).

2.- The volume that is not excessive, but enough to feel full at the end of the meal. A meal that provides vegetables, pasta or rice (in 80% of the normal ration) plus low-fat meat or fish, can allow you to exercise between two and three hours after eating.

3.- The time will be reduced or lengthened depending on the type of exercise. To go out with the bike, many can start to flatten in an hour or an hour and a half (some even earlier). To go running or do intense physical efforts we will have to leave two hours or even three.

But it must be remembered that this time varies according to: the tolerance of each one to post-ingestion exercise and the different duration of digestion between individuals. However, when fat is reduced in a meal (which is the nutrient that is most difficult to digest), digestion is usually no longer so heavy and is generally facilitated, the long digestions that some individuals present are normalized and you can start the exercise before. Each one must find out what is that adequate period of time between food and exercise.

It works very well, if the time elapsed after the pre-exercise intake is greater than three hours, take alimeLight snack such as fruit, energy bar or similar shortly before starting the exercise. It is advisable to eat a moderate meal before the effort, with the characteristics mentioned, and during the exercise, take a maintenance energy intake.