Dispelling those myths on free radicals zt
There is an old wives’ tale that says we are born with a predetermined number of heartbeats, and because exercise uses them up faster, that causes us to die sooner.
In a similar context, exercise increases free-radicals production, and free radicals are damaging to the body. Thus, if you buy into the heartbeat theory, as well as the notion that extra free radicals from exercise are dangerous, it would seem that exercise is a very bad idea. That’s not true, but it makes for interesting cocktail party chatter.
Last week, I debunked the heartbeat theory. Now, let’s take a look at free radicals.
What is a free radical? It’s an unstable atom.
Huh? Let me explain.
The body is comprised of cells made from molecules that are made up of atoms joined by chemical bonds. The outer ring of an atom is comprised of electrons. A stable atom has a full complement of electrons. That means it doesn’t need any additional electrons. It’s happy the way it is.
When an electron is missing, the atom becomes unstable and it needs to obtain an electron to regain stability. It becomes a free radical, in other words, and here’s where the trouble begins.
A free radical will attack any structure that is nearby and steal an electron. That creates a new free radical and, in turn, the new free radical steals an electron from somewhere else to regain stability. And so it goes in a chain reaction that, once started, can be damaging to the cell.
Free radicals occur naturally when oxygen is used by the body in metabolism. They also can be created by the immune system for specific purposes and can be caused by environmental pollutants.
Antioxidants
Free radicals are neutralized by antioxidants. An antioxidant can stop the chain reaction by donating an electron, thus making a free radical stable again. More importantly, an antioxidant does not become a free radical even though it has lost an electron because it’s stable with or without that electron.
Antioxidants come from two sources. The body produces them or you can get them from your diet. Antioxidant supplements loaded with vitamins C and E and other agents have attracted attention in recent years, but research on their effectiveness has not been conclusive. Natural foods, fruits and vegetables are good sources of antioxidants. It’s always a good idea to load up there, especially if you exercise.
Exercise
Now, let’s return to the central issue. Is exercise bad because it uses up extra heartbeats and because it produces extra free radicals?
Last week, I explained how the body makes adaptations called the training effect. One aspect of this is a reduction of the heart rate at rest, which saves lots of heartbeats, many more than are expended during exercise.
In the same way, another aspect of the training effect is the production of more antioxidants. You produce more free radicals during exercise, but your body stands ready to cope with them because there are more antioxidants available.
Regular exercise forces the body to change, to function better and to stay one step ahead of the negative things that exercise may cause. The key is regular exercise because that brings about a training effect. Random exercise does not.
This suggests that those who don’t train regularly, but go out periodically and push themselves hard, don’t achieve helpful adaptations such as increased antioxidant production. So-called “weekend warriors” may not only be risking orthopedic damage with their haphazard approach, but they also may be inviting increased free-radical damage as well.
The bottom line is that exercise may use up extra heartbeats and increase free-radical production, but it also takes steps to cope effectively with these challenges. Yes, exercise is a good thing, but you already knew that.