The importance of antioxidants for the endurance athlete 

Although adhering to a well structured training regime is the best way for athletes to achieve good results they need to look to their diets and dietary supplements to maintain good health and to improve post-event recovery. There are many different categories of supplements but perhaps the most important, but misunderstood, of these are the antioxidants.

Numerous types of antioxidants occur; some are produced by our bodies while others are derived from the diet. Free radical-induced oxidative stress is an inevitable consequence of prolonged exercise and results in tissue damage, excessive fatigue, delayed recovery and overtraining. Endurance athletes need to ensure that they have an adequate intake of a wide variety of effective plant-based antioxidants.

Free radicals
Free radicals (including reactive oxygen species) are unstable molecules that can cause damage to DNA, cell walls and other structures. Most free radicals are by-products of the normal processes of energy production by the cell. A useful analogy is a car engine that releases exhaust gases during the process of energy production. Free radicals are the body's equivalent of a car's exhaust gases. The more work the engine does the more gases it will produce. Similarly, the harder and longer we exercise the more of these toxic free radicals we produce.

Antioxidants
Antioxidants are substances that neutralize the harmful effects of free radicals. In order to counter the damaging effects of these unstable molecules the body has developed an elaborate antioxidant defense system.
Although we produce our own (endogenous) antioxidants we also require a supply of antioxidants from our food. Some well known dietary antioxidants are vitamins A, C, E; ß-carotene, selenium and plant based antioxidants such as curcumin, quercetin, resveratrol and rutin.

Importance of antioxidant diversity
One of the most important concepts we need to appreciate in this context is that we require a wide variety of antioxidants to deal with the many different types of free radicals that are released during energy production. One or two so-called "strong antioxidants" are unable to neutralize all free radical species. Furthermore not all antioxidants can reach all the parts of every cell. For instance vitamin E functions primarily in the "fatty" parts of the cell while vitamin C can only access the "watery" areas. Some antioxidants cannot cross the 'blood-brain barrier' and therefore cannot provide protection for that vital organ.

Endurance athletes need additional antioxidants
The body requires higher than normal levels of antioxidants to cope with the vastly increased quantities of free radicals produced during prolonged, strenuous exercise. One way of building up endogenous antioxidants is to exercise frequently. Athletes who train regularly have far greater quantities of endogenous antioxidants than those who exercise intermittently or not at all.
As a result of exercise-induced free radical overload endurance athletes also need to boost their intake of plant-derived antioxidants.
A number of clinical studies have shown that taking a wide range of plant-based antioxidants can help to counter free radical damage in endurance athletes. In addition they improve post event recovery and accelerate muscle repair – especially in older athletes.  

Too much of a good thing
On the other hand several clinical trials have failed to show that taking only one or two so-called "strong" antioxidants like vitamins C, E or Co-enzyme Q10 provides any benefit at all. In fact vitamin C in high doses (1000 mg per day) can be harmful as it slows post event recovery and aggravates muscle inflammation commonly associated with vigorous exercise.

Spices are the best source of antioxidants
Plants provide an extensive range of valuable antioxidants and natural anti-inflammatory compounds. Spices are the richest food source of these compounds followed by fruit, vegetables, nuts and beverages such as tea and coffee (American Journal of Clinical Nutrition, July 2006).
Scientists have discovered that many plant-based antioxidants are vitally important in the prevention of diseases such as heart disease, cancer and Alzheimer's disease – just some of the illnesses that are associated with free radical damage. As these plant compounds are powerful, effective free radical scavengers it is not surprising that they provide benefits to athletes who are frequently exposed to free radical-induced oxidative stress.

Antioxidant variety more important than strength
While it is important for everyone to ensure that they have an adequate intake of antioxidants, it is unwise to take excessive amounts of only one or two antioxidants like vitamin C or E as they may do more harm than good.
To ensure adequate protection against free radical damage, endurance athletes need to eat adequate quantities of fruit, vegetables and spices and take a supplement rich in an array of different plant-based antioxidants.

A comprehensive spice supplement is the best way for athletes to ensure that they have an adequate intake of antioxidants. 

Carbohydrate enhancement
One of the greatest difficulties facing athletes who compete in endurance events is maintaining a readily available supply of energy in the body. In order to achieve this, muscle carbohydrate stores, in the form of glycogen, must be continuously replenished. In an event lasting more than one-and-a-half hours, glycogen stores become depleted, and for the remainder of the event the athlete has to rely on external sources of energy, such as high carbohydrate drinks, which are inferior to glycogen as an energy source. Post event re-synthesis of glycogen is also very important, and the two hours immediately following prolonged exercise is the crucial time for this process to occur.

Fenugreek has been shown to have a strong effect on glycogen replenishment; increasing post-event re-synthesis by over 60 percent in some endurance athletes. While its effects on glycogen re-synthesis during an event have yet to be tested, fenugreek is likely to exhibit a similarly beneficial effect during, as well as after, exercise.

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