It is undeniable the great benefits that physical exercise brings to health, but it could also have a negative impact, which would be given by an increase in oxidative stress. Of course, this will depend on the level of training, the intensity and duration of the exercise, the gender, and the age of the person exercising. Sometimes it will be necessary to strengthen our defenses against oxidative stress with antioxidant supplements. If you are over forty, take note.
What is oxidative stress
The nutrients we ingest through the diet are converted into energy through a series of biochemical reactions within the cells. These reactions are part of normal metabolism.
As part of these reactions, intermediate products are generated, such as free radicals, reactive oxygen species (ROS) and reactive nitrogen species (RNS), which are unstable molecules because they contain one or two atoms that do not have their electrons paired, meaning they are unpaired. To stabilize, these free radicals must "steal" electrons from other molecules (the molecule from which they "steal" will be oxidized).
The victims of free radicals, ROS, and RNS are important biomolecules such as lipids that make up membranes, proteins that may be receptors in the cell, mediators, or hormones; and DNA itself, which contains all our genetic information. Oxidation causes a structural change in these molecules, and this alters their function.
Fortunately, we have an antioxidant defense system (What are antioxidants in simple words) to counteract the production of ROS/RNS. Antioxidants are defined as any substance that, when present at low concentrations, significantly delays or prevents the oxidation of other biomolecules like lipids, proteins, or DNA.
When the balance between the presence of oxidizing agents (free radicals, ROS, RNS) and antioxidants is broken, a condition known as Oxidative Stress (Oxidative Stress myth or reality) occurs.
Why exercise can cause oxidative stress
Exercise increases energy requirements. To meet this demand, metabolism must increase.
It is estimated that between 2% and 5% of the oxygen consumed during normal mitochondrial metabolism (The mitochondrion is a small organelle within the cell where reactions occur) can be converted into radicals and their products. Under conditions like exercise, which demands more energy in many tissues, mainly muscle, there is an increase in oxygen use in the mitochondria, resulting in greater radical generation.
The increase in metabolism due to exercise results in higher production of superoxide-type radicals, which are transformed into hydrogen peroxide (H2O2) by an enzyme (superoxide dismutase). H2O2, a molecule that easily crosses cell membranes. Normally, this peroxide would be neutralized, turning into water and oxygen, through other enzymes: catalase and glutathione peroxidase, which are part of our internal or endogenous antioxidants (What are antioxidants in simple words) defense system. But when these transformations do not occur because there is no antioxidant defense, H2O2 is converted into the hydroxyl radical, the most toxic ROS due to its high reactivity.
Numerous studies have shown that muscle cells also release superoxide into the extracellular space, so free radicals easily reach the blood and act on other cells.
Although the generation of free radicals during exercise occurs mainly in skeletal and cardiac muscles, some reports have shown that the concentration of several oxidative stress markers increases immediately in plasma after intense exercise.
Why athletes are not affected by oxidative stress
Most research has always shown the increase in free radical generation that accompanies exercise; however, professional athletes are generally very healthy individuals. In fact, experiences in both animals and humans subjected to intense and prolonged exercise suggest that they become more resistant to oxidative damage.
A group of researchers decided to study this question, with a group of healthy volunteers who were not athletes, aged between 19 and 29 years. They conducted experiments where they subjected them to controlled intense exercise using a cycle ergometer, a device that can regulate pedaling intensity, measure heart rate, oxygen consumption, and other variables.
They used three intensities, but with a one-week interval between them. At the end of each exercise, a blood sample was taken to measure the concentration of antioxidant enzymes in plasma. The good news is that the results showed that the concentration of antioxidant enzymes increased with exercise.
According to these results, the increase in free radical production during exercise would be counteracted by the also increased levels of endogenous antioxidants.
However, it must be considered that many studies that have analyzed the relationship between free radicals and exercise have found indirect markers of lipid oxidation, which indicates that oxidative damage did occur.
Age factor and antioxidants
The ages of the subjects in the mentioned study were between 19 and 29 years; however, it is also known by science that the production of endogenous antioxidant enzymes decreases after the fourth or fifth decade of life.
The age factor plays a determinant role in the antioxidant balance. Therefore, in addition to trying to consume a diet rich in antioxidants, (What are the best antioxidant foods) if we are over 40–50 years old, we must include a good antioxidant supplement, like the latest generation made with nanotechnology. (What is Nanotechnology in simple words)
The Nano Omega 5 (What are the benefits of Omega 5) from GranaGard® is a powerful natural antioxidant with multiple mechanisms of antioxidant action. Omega 5 has been transformed into a nanoemulsion, allowing it to dissolve in both aqueous and fatty environments, reaching all the cells of our body.
If you are over forty years old, practice regular exercise, and want to take care of your health in the best possible way, now you know that you need to provide extra help to your body to balance the oxidative stress that can be caused by physical activity.
Antioxidant supplements for workout
October 2, 2024
