Free radicals are molecules constituted by groupings of atoms rendered unstable by the lack of an electron in one of the outer sockets.
This instability makes the radical extremely reactive and, therefore, it is ready to react with a neighbouring molecule.
Oxidising or reducing behaviour
If the reaction constitutes accepting an electron, we can term it oxidising behaviour, while if the reaction involves donation of electrons, we can term it reducing behaviour. For this the free radicals, although they are produced by the body to protect itself from the etiological agents of bacterial nature mainly, excess amounts are potentially toxic and may cause damage to the body and, in particular, to DNA.
Free radicals and sports
Many studies have shown that vigorous physical activity, in proportion to its intensity and duration, can cause an increase of free radicals caused by several possible factors, including an increase in oxygen consumption, an increase of phenomena of ischemia - reperfusion of muscle tissue, autoxidation of catecholamines, release of metals and theactivation of neutrophils.
However, one must remember that workout and physical training causes an increase in level of free radicals on the one hand and on the other increases the levels of different antioxidant enzymes.
The body is in fact equipped with complex and efficient self protection systems with respect to free radicals: protective substances so activated are defined as antioxidants and, in turn, are divided into endogenous and exogenous.
Endogenous antioxidants
Endogenous antioxidants are mostly enzymes that work in conjunction with certain minerals such as selenium, copper, zinc, manganese and iron.
They act as antioxidants for other substances also such as, for example, uric acid, bilirubin, transferrin, albumin.
Exogenous antioxidants
Exogenous antioxidants, in addition to the said minerals to match enzymes, are vitamin E, vitamin C, beta-carotene, flavonoids, lycopene, resveratrol, alpha-lipoic acid and ubiquinone.
|
MAJOR ANTIOXIDANT FOODS |
||
|
Vitamin E |
Oils Vegetables Nuts and Seeds |
Wheat germ, sunflower, soybean, rapeseed and corn Spinach, broccoli Peanuts, sunflower seeds, muesli |
|
Vitamin C |
Fruits Vegetables |
Blueberries, strawberries, oranges, kiwi Red peppers, brussel sprouts, potatoes, broccoli |
|
Betacarotene |
Fruits Vegetables |
Citrus fruits, melons, apricots, fish Carrots, spinach, sweet potatoes, peas, lettuce, chicory |
|
Selenium |
Vegetables Miscellaneous |
Spinach, mushrooms, Brazil nuts, sunflower seeds |
|
Flavonoids |
Vegetables Fruits |
Onion, lettuce Apples, oranges, grapes |
|
Lycopene |
Vegetables |
Tomatoes, melons, papaya |
|
Resveratrol |
Fruits |
dark-skinned grapes |
|
Alpha-Lipoic Acid |
Vegetables Meats |
Potatoes, carrots, beets Red meat |
|
Vitamin Q |
Oils Walnuts Vegetables Legumes |
Soybeans, wheat germ Hazelnuts Spinach, garlic, cabbage Beans |
- Commission for the Supervision and control of the Doping and the protection of health in sports, Dr. S. Donati
- Department of Drug Abuse, Drug Addiction and Doping Department - Istituto Superiore di Sanità, R. Pacifici, S. Pichini, I. Palmi, L. Mastrobattista, C. Mortali, P. Zuccaro
