Free Radicals

Learn How To Control These Health Damaging Molecules

By Xavier Fox

Many of the articles about exercise and nutrition mention free radicals, but they do not take the time to truly explain what they are, how they come about, and how to defend against them. This is important information to know, because it can help you add more muscle, lose more fat and stay healthier in the long-term. It is always easier to have power over something when you have in-depth knowledge of exactly what it is and how it works. So, let’s take a look at free radicals and how we can effectively deal with them to make ourselves healthier.

We will begin with a quick lesson in chemistry. We all know that our body is composed of combinations of millions of cells. These cells can be broken down into molecules, and molecules can be further broken down into one or more atoms that are connected by chemical bonds. An atom is almost as basic as you can get, but even they can be broken down into their elements. Atoms have a nucleus at the centre, neutrons, protons (positively charged ions) and electrons (negatively charged ions). The nucleus is mainly composed of protons, and the electrons orbit around the nucleus just as the Moon orbits the Earth, and the Earth orbits the Sun. The number of electrons will usually be dependent on how many protons are in the nucleus, and they will be layered in concentric shells around the nucleus. As the shells closest to the nucleus fill up, electrons spread to the next outer shell. There are the same number of electrons spinning in opposite directions as well to maintain an even charge. This is due to the atom trying to maintain a balance of charge. As you may have read in various articles in the past, our body is always attempting to maintain balance, and this is even true at the atomic level.
The outer shell is very important to the way that the atom interacts with other atoms. When an atom has an outer shell that is “full” (has a balance of electrons to make the electron to proton ratio even) it tends not to react with other atoms and is called an “inert” atom. This is known as the “ground state.” However, some atoms do not have a completely full outer shell, as they lack a certain number of electrons, and they become unstable. Hmmm… I seem to have a few friends that must lack electrons in their outer shells. Anyway, since our body is always trying to find balance, it finds a way for these atoms to fill their outer shell by adding the required electrons. Since atoms cannot go to the psychiatrist, they must find another way to become stable. It appears that the best way for them to accomplish this is to become a thief and steal an electron from another atom, or in some cases, they become generous and donate the extra ones – it probably just depends on their upbringing. In addition, some atoms that went to etiquette class will “bond” with another atom by sharing electrons in their outer shells; this is the most common method, called a covalent bond. The sharing of electrons between two atoms provides the molecule with the best method for maintaining stability.
Don’t let the fact that they share electrons with each other make you start feeling all warm and fuzzy inside about these atoms. Free radicals are the atoms that are going around with at least one unpaired electron in the outer shell while still being capable of existing independently. When they steal or form a covalent bond with another atom in order to reach a ground state, they end up forming a new free radical, because the atom that they took the electrons from is now deficient in electrons and now it is a free radical itself. Then, since it can’t take its electron back, it finds a weaker and smaller atom, punches it in the eye and takes one of its electrons. Then, that new free radical finds an atom to pick on, says, “Give me your lunch money” and takes an electron. Before you know it, an entire new community of thousands of bullies have been created.
Of special concern to those that exercise are free radicals that involve oxygen. They are called reactive oxygen species (ROS), and they have oxygen at the centre and two unpaired electrons in the outer cell nine, giving it a charge of minus two. As you may remember form previous articles on creatine, the electron transport chain (ETC) in the inner mitochondria membrane uses oxygen to manufacture energy from adenosine triphosphate (ATP). Oxygen is the molecule that accepts electrons from a donor in order to create energy in the mitochondria. Studies show that up to 5% of oxygen intake during exercise will end up in the formation of what is known as a superoxide radical. Superoxide radicals are biologically very toxic, and they are damaging to the molecules around them due to their need to steal electrons. During exercise, oxygen demands increase greatly, which means that as more and more oxygen gets consumed, more and more of it turns into superoxide and free radicals, and more and more damage occurs. Here we are trying to be healthy and exercising, and we are causing all kinds of damage to our bodies.
While reading through bodybuilding articles, you may have come across the term “peroxidation.” The polyunsaturated fatty acids in our system are mostly concentrated in cellular membranes and in low-density lipoproteins, which of course are the “bad” type of cholesterol. Polyunsaturated fatty acids allow atoms to transport though cellular membranes. Free radicals find it easy to steal electrons from lipid membranes (maybe because most fat things are lazy), and they will rapidly assault the carbon to carbon bond of the polyunsaturated fatty acids causing the weak carbon to hydrogen bonds in the acids to readily give up an electron and the carbon is left with one less electron than it needs. This carbon-centred free radical causes the molecule to rearrange and a molecule called a conjugated diene (CD) is formed. The CD molecule joins with oxygen to create a peroxy-radical. Guess what happens? The newly formed peroxy-radical finds a lipid molecule within the membrane, and then here we go again. Before you know it, there are radicals everywhere, and our cellular membranes are involved in guerrilla warfare.
There are many different types of free radicals that exist in our bodies. However, as was mentioned earlier, we are more concerned with the ROS types that have oxygen centres, because they are the ones that reap havoc on our mitochondria; specifically O₂- ions. These are the superoxide anion (O₂- ), the hydroxyl radical (OH), singlet oxygen (1O₂), and hydrogen peroxide (H₂O₂). As was stated before, the more oxygen we consume during a workout, the greater the number of oxygen centred free radicals that are formed. Sometimes, the free radicals superoxide anions and hydrogen peroxide free radicals combine to form the hydroxyl radical, which is the most damaging of the free radicals. Hydroxyl can also be produced when hydrogen peroxide reacts with copper and iron in our system. Hydrogen peroxide can also be converted into water if an oxygen molecule is taken away, however, it can very well be converted into the singlet oxygen free radical as well if the hydrogens are removed. Singlet oxygen is somewhat unique, because it has all eight electrons in its outer shell, but it has one complete orbital of the same energy level completely level. This causes the electrons to easily jump to the other orbital, and thus a free radical is formed, and the chain reaction begins. Why can’t the molecules in our bodies just play nice?
Unfortunately for us, the minerals copper and iron bring about the formation of many of our free radicals. These two minerals are very essential to our health, especially iron, which keeps our red blood cells healthy and functioning properly. Iron has only one electron in its outer shell, but copper’s outer shell is full. However, copper must be rather wimpy, because it gives up an electron from its outer shell without much of a fight. These two transition metals are often the catalyst for oxidation reactions that create free radicals, but that sure doesn’t mean that you should try to remove them from your diet.
Free radicals do a lot more than just create chain reactions where more free radicals are formed. They can actually alter the makeup of a molecule to the point that its function is completely destroyed. Molecules that have been attacked by free radicals often end up being transported out as waste by our immune system. This really stinks when the molecules that are being removed are the ones that help our muscle recuperate and grow. If this process is permitted to go on inside the muscle, you will give in to fatigue much sooner than you want to and you will also not recuperate as effectively.
So, what can be done about this? Well, it’s time for the record man to queue up the Superman soundtrack, because there is a powerful free radical fighting system known as antioxidants that have come to save the day. Antioxidants are compounds that have the ability to donate an electron from their outer shell without becoming unstable and changing their characteristics. This enables them to neutralize free radicals and stop the potential chain reaction of free radical production, which can lead to cell damage. This is because the free radical now has a complete outer shell, and the antioxidant doesn’t need to replace the electron it lost and still be able to retain its characteristics. Yay, everyone goes home happy. Our body naturally attempts to produce antioxidants on its own in order to neutralize the free radicals that are created. It creates superoxide dismutase (SOD), catalase and glutathione peroxidase as electron donators in order to combat free radicals.
Before you start to think that you do not have to worry about free radicals anymore, it is important that you know that during exercise when oxygen consumption increases dramatically, our ability to combat free radicals may be overcome by the amount of free radical production. When free radicals cannot be removed from our system at a quick enough pace, lipid peroxidation will occur. In addition to destroying muscle, free radicals have been implicated in helping to cause cardiovascular disease, cancer, Alzheimer's disease, and Parkinson's disease. Therefore, we must find a way to bolster our antioxidant defences so they can equal or exceed the rate of free radical production.
Our body attempts to manufacture antioxidants on its own as long as it has all of the resources it needs. To help our body reload its arsenal, it is a good idea to consume plenty of healthy foods such as fruits, vegetables, seeds, nuts, meat and oil. They contain the antioxidants to help us battle free radicals. We can also take antioxidants in supplement form, namely the vitamins A, C, and E and selenium.
Our antioxidant defence system act in two parts. The first is within the fat-soluble layer of the cell membrane that contains the antioxidants vitamin E, beta-carotene and coenzyme Q10. It is here that vitamin E does most of the work, and it is considered to be the most powerful of the antioxidants. Inside the cell, vitamin C, glutathione peroxidase, superoxide dismutase (SD) and catalase take over because they are water-soluble and can exist in that layer. Make sure your supplement cabinet contains multi-vitamins and coenzyme Q10. Supplementation is especially important after exercise, because it is within the first 24 hours after exercise that free radicals are most active. Eating properly and supplementing will help you recover faster from workouts, because it will combat the damage caused by oxidation associated with exercise.
Okay… we have been bashing free radicals and making them sound completely evil, but as they say, every storm cloud has a silver lining. Free radicals do serve some purpose in our system. When foreign substances or damaged tissues are in our system, our body needs a way to know it is supposed to remove them. Free radicals are used by our immune systems as “markers” so it knows which substances it is supposed to remove to keep us healthy. Now, this brings up the question of whether or not antioxidant supplementation weakens our immune system. On this subject, all that can be said at this time is that there is no evidence to suggest that taking antioxidants will weaken the immune system by suppressing free radicals.
Keep your body functioning properly by eating healthy foods and using supplements to combat the damage caused by free radicals. Keep your mitochondria intact so your workouts can be explosive and intense and keep muscle tissue damage to a minimum as well by learning about free radicals and how to minimize their negative effects. Every bit of knowledge that you gain teaches you one more way to maximize the results of the efforts you put in to improve your physique.