Sports Nutrition


  1. Introduction……………………………………………………………….
  2. Use by athletes…………………………………………………………….
  3. Role of antioxidants in the body…………………………………………
  4. Antioxidant supplementations and athlete’s performance…………….
  5. Adverse impacts of antioxidants in the body…………………………….
  6. Recommendations………………………………………………………….


These are the chemical agents which provide the safety to human body from the damage caused by the free radical in the body. Antioxidants have the capability to neutralise the free radical and prevent the damage. Basically antioxidants are phytochemical, vitamins and other nutrients which save our body from the attack of free radical damage. Free radical damages are generally very harmful for the body since that is related with the heart diseases and cancer in the body (Schmitz, 2009). The figure below shows the structure of antioxidant. Free radicals are the particles which get originated from the toxic elements inside our body and cause serious harm to the body parts by not allowing proper oxygen flow inside our body.
Generally antioxidants are found in phytochemical elements, vegetable and fruits are the rich sources of the antioxidants. Two main benefits of the antioxidants are their capability to save against cancer and heart diseases. Some of the well known examples of the antioxidants include vitamin E, C and Beta Carotene (Kerksick, 2008). Other then Vitamin E and Vitamin C other sources of antioxidants include various acids like Lipoic acid, ascorbic acid and other acid which are a part of the fruits. List of all antioxidants is as given below:
List of Oxidants
Sr. No.
@-Tocopherol (Vitamin-E)
Ascorbic Acid (Vitamin-C)
Lipoic Acid
Uric Acid

The figure below shows the lipid action of antioxidants on free radicals: 

Free radicals particles contain the negative oxygen ion with them which are free in nature and try to oxidize by reacting with other chemical particles (Grivetti, 1997). The hydric ion present in the lipid structure of the antioxidants get reacted with the free radical particles in order to neutralise the free oxygen molecules contained in the free radical elements which are very harmful for the body since they do not allow smooth flow of oxygen inside the body. These hydric ions react with free radicals and neutralise these particles there by providing the free oxygen flow inside the body which is very crucial for the proper functioning of the body. Since this electron ion present in the free radical particles tend to react with the digestion system of the body or try to damage the cells inside the body these damaged cells inside the body do not get recover again hence man suffer with the problem of immature ageing problem that is why neutralisation of free electron in body in very important (Richard B, 2007).  

Use by Athletes

Athletes do exercises and due to these exercise chemical reactions takes place in the body  which gives rise to the free radicals (called reactive oxygen species) in their body and hence causes oxidative stress to their body, dietary oxidants help in the releasing the oxidative stress from the athlete body. But their role as the performance enhancer is still doubtful. Rigorous training of athletes enables them to release more amounts of free radicals. Strenuous exercise enhances the need of oxidants for athletes (Joel M., 2006). These free radicals damage the cells, DNA and the aerobic capability of athletes. These free radicals also stresses the muscle cells of the body, to prevent that antioxidants which are taken by the foods and supplements helps in maintaining integrity of the cell membrane for the athletes thereby carry out movement of oxygen for effectively and efficiently.       

Antioxidants which are contained in Vitamin C provides the capability of powerful immune system for the body since most of the athletes have the risk to suffer with the disease of URTI which is Upper respiratory tract infection. Since due to the competitive training and exercise athlete generally suffers from coughing problem, Vitamin C helps the athletes to combat these problems. The impact of antioxidants is slow in nature i.e. it takes several years to show its effect (Hoffman, 2009).

Antioxidants are considered to be as the insurance agents against the free radicals since in the longer time duration they help the athletes to combat free radicals damage. Antioxidants are must for the diet of athletes who exercise hard in their life since these antioxidants help in reducing the infection from the body and make fast recovery for any kind of damage to their body (Michael, 2008).
Role of antioxidants in the body
Free radicals cause harm in the body by affecting respiratory system and cause stress in the body. The main purpose of the antioxidants is to neutralise these free radical particles and allow the free movement of oxygen in the body. Antioxidants help in maintaining healthy balance in the body (Boozer, 1995). By consuming antioxidants regularly they help in removing bacteria from our immune system. Free radicals attacks on the body cells hence do not allow the cells to reproduce correctly there by giving rise to a number of diseases in the body like coronary heart disease, cancer, inflammatory diseases and cataracts etc.

The source of free radical in our body originates from our eating habits, our living conditions and our society etc. These particles give rise to the free radicals which are basically unstable oxygen molecules with some amount of free electrons with them. Hence these free electrons available with the free radicals get reacted with our body system and hence causes damage to our body (Clark, 2000). These free electron pair available with the free radicals wants to oxidize. This oxidation process carried out by the free radicals in carcinogenic in nature. Hence this oxidation process carried out in this manner can cause premature ageing, cancer, cataract and other immune system related problems inside the body.

 Antioxidants have the other free electrons pair with them due to these the electron pair available with free radicals get reacted with these and get neutralises hence saving our body from the harm caused by the free radicals inside our body (Lyle BJ, 1999). The reaction of the antioxidants with free radicals neutralise these particles giving rise to free flow of oxygen inside the human body. The action of antioxidants in our body is like sponges and hence these sponges soak up the free radicals particles having the free valence electrons with them.

Antioxidants which are essentially taken in our body from the sources like vegetables, fruits, and certain oils like lemon oil and orange oils help the body to maintain the proper amount of antioxidants in our body which continuously fights with the free radicals (Harman, 1956). These oils added with certain other nutrients like Ningxia wolfberries, juices from blueberries and pomegranate provides the rich source of antioxidants which neutralises the free radical particles in the body.

The main roles served by the antioxidants inside our body are as follows:
  1. Increased energy Levels: The antioxidants which help the body to recover fast from the tough physical work done by the body. This physical exercise done by body try to break the cells, these cells get damage and do not remain in proper condition for the further reproduction system which is required by the body since in body due to intense physical work there is always wear and tear happens inside the body and if reproduction system works properly then the energy level of the body remains in the proper amount (Harman, 1972). Antioxidant neutralise free radicals and hence body cells do not get damage easily and the reproduction system remains in proper condition and there is almost zero wear and tear in the body. Hence the energy level inside body is well maintained and body feels energetic.  
  2. Protect immune system: The free radicals particles tries to get oxidize quickly by reacting with the immune system of the body hence thereby causing damage to our immune system (Glewwe P, 2001). Free radical particles when enter inside our immune system do not allow immune system to make proper flow of oxygen inside the body.
  3. Better liver functioning: Antioxidants particles neutralises the free radicals hence thereby giving the proper functioning of the liver (Whitley JR, 1951). These antioxidants help the liver to filter out the toxins elements from the food particles which enter inside body with food particle and harm the liver.
  4. Proper Sleep cycle: Antioxidants helps in maintaining the sleep cycle inside body thereby providing the proper body functioning. This antioxidant maintain the sleep cycle by releasing the stress from the body so that person can complete his sleep cycle and maintain the body functioning in proper manner (Mauro G., 2008).
  5. Protect from cancer: Antioxidants helps the body to save from the particles which causes cancer inside human body by neutralising these agents. Antioxidants keep our blood in good health and hence due to that our body cells do not die so easily hence diseases like cancer can be cured very well. Since the main reason of the cancer disease is the dying cells inside the body.
  6. Strengthen capillary walls: Antioxidants helps in protecting the capillary walls inside the body by maintaining the blood in good condition (Christen, 2001). These capillary walls help in protecting from the cardiovascular diseases.  
  7. Skin Protection: Antioxidants protects the skin from any kind of damages by saving the elastin fibres. It saves from the various allergies which arise due to the harmful chemicals taken inside the body with food and other environmental interactions.
  8. Ageing protection: The problem of immature ageing can also be cured by the action of antioxidants inside the body since antioxidants help in building atherosclerosis which prevents the immature ageing problem in human body. Generally the body cells get damage slowly due to the hard work out and do not get heal soon, antioxidants with their protective action allow these cells to grow again so that the body growth can be carried out in smooth manner and immature ageing can be stopped in human beings.

Antioxidant supplementations and athlete’s performance

There are various researches which have happened in order to get the effects of antioxidants on athletes. The following table summed up some of the studies done on the antioxidants and their corresponding impacts on the athlete’s performance:

Type of Vitamin
Type of exercise
Amount and duration( pre, during or post exercise)
Effects on performance
Dietary antioxidants
Vitamin C
Eccentric exercise
4 weeks
Small beneficial effect but unacceptable risk of harmful effect
Botanical antioxidants
Vitamin C
3 weeks
39% increment in run time
Fructose and maltodextrin
3 weeks
No significant difference
Nicotine patches
2 weeks
Considerable enhancement in cycling time

Blind controlled trial
Fish oil

Eccentric exercise

3 weeks
Small or trivial impacts

  • A study done on dietary antioxidants on 23 female runners who undergoes eccentric exercise and overload training in their regular schedule. Athletes were given Isocaloric drink which was having blackcurrant extract, vitamin C and Placebo in it. After 3 weeks of training and performance test there were small benefits of the antioxidants while the risk was there of harmful effects of the medicine.

  • Another study done on botanical antioxidants which was related to the recovery of damaged cells and performance of athlete. After two weeks of exercise with team sport athletes they were given almond diet and as the result of this there was 46% increase in run time of the athletes (Comstock, 2000).

  • A study done on the impact of Fish oil which was carried out with the 10 athletes for 3 weeks who were undergone eccentric exercise shows there were small impact on the recovery of damaged cells inside the body and the energy level enhancement as well.

  • A study done on the 51 cyclist who were given doses of carbohydrate at a rate of ~70 g.h-1 shows sign of massive improvement in their run time of more than 43%.

Adverse impacts of antioxidants on human body

  • In a study carried out to identify various possible adverse impacts of antioxidants on human body certain phenomenon were measured for any athlete. Insulin sensitivity, glucose metabolism and body’s capability to produce natural antioxidants were measured before the experiment. The most harmful impact of the antioxidants was the prevention of insulin sensitivity and increase in body’s inner capability to fight with the diseases (Adkison, 2005). Also certain mediator substances which are essential for the body functioning were not able to form inside the body as harmful impact of antioxidants. The following diagram illustrates the above phenomenon:


  • In one of the study which was conducted for the Alpha-Tocopherol Beta-Carotene (ATBC) it has been found that the patients who were taking excess amount of beta carotene and Vitamin E were 16% more susceptible of attack of lung cancer.
  • In another study which was named as Caroteniod and Retinol Efficacy Trial (CARET) the patients were given 30 mg of beta carotene and Placebo was found to have 28% more chances in lung cancer.
  • A study named physical health study conducted with some patients who were treated with 50 mg of beta carotene; Vitamin E and Vitamin C were found to have toxic effects as cognitive decline after several years of their treatment.
  • An athlete who was given 800 mg of Vitamin E resulted in worse immune system and the person got died after some time due to immune system failure.
  • An age related eye disease study has shown that the person who was given Vitamin C (500 mg), Vitamin E (400 IU) and Beta Carotene (15 mg) lost his eye sight due to affect of antioxidants on his visuals.
  • The antioxidants like ascorbic acid can cause serious damage to the urine system and can also cause long term impacts on the body (Hatfield DL 1999).
  • The antioxidants like B-carotene, Vitamin A and Vitamin C can increase the mortality in human being.

  • Antioxidant are taken in order to deoxidize the oxygen but when the dose of antioxidants taken in proper amount then only they work better but when overdose is taken it can cause various harm since the Beta carotene, Vitamin E and Vitamin C are all very harmful elements if taken in excess quantity inside body. So person should take care that the overdose does not happen in body.
  • Taking the natural sources of the antioxidants is better than taking the chemical directly so the athletes should eat more of vegetable and fruits as the part of their daily diet since they do not have any kind of side effects on the body. So a balanced diet is very important for the athletes in order to take the proper amount of antioxidants.
  • Taking of excess supplements will not work in absence of the proper amount of exercise, so athletes have to exercise regularly in order to balance the effect of supplements taken by them without which these supplements can cause serious harm to the body.
  • For very hard work out like climbing up the hills or long races proper amount of vitamin C is required inside the body since Vitamin C keeps the energy level of the body up and help in heeling up fast. 


  • Stephen M Schmitz, 2009, “Nine week of supplementation with a multi nutrient product augment gain in lean mass, strength and muscular performance in resistance trained men”, Journal of international society of sports nutrition.
  • Chad M Kerksick, 2008, “Nutrition administration and Resistance training”, Journal of international society of sports nutrition. 
  • Applegate and Louis E. Grivetti, 1997, "Search for the Competitive Edge: A History of Dietary Fads and Supplements." The Journal of Nutrition
  • Campbell and Richard B, 2007, "International Society of Sports Nutrition position stand: protein and exercise." Journal of the International Society of Sports Nutrition
  • Stager, Joel M.,2006, “Chocolate Milk as a Post-Exercise Recovery Aid”, International Journal of Sport Nutrition and Exercise Metabolism
  • Elizabeth A and Louis E. Grivetti, 1997, “Search for the Competitive Edge: A History of Dietary Fads and Supplements”, Journal of Nutrition
  • Hoffman, 2009, "Examination of a pre-exercise, high energy supplement on exercise performance." Journal of the International Society of Sports Nutrition
  • Gleeson, Michael, 2008, “Dosing and Efficacy of Glutamine Supplementation”, Journal of Nutrition
  • CE Boozer, 1995, “Air Oxidation of Hydrocarbons”,  Journal of the American Chemical Society
  • Clark, 2000, “Nutrition and Athletic Performance: Position of the American Dietetic Association”,  Journal of American Dietetic Association 
  • Lyle BJ, 1999,  “Antioxidant intake and risk of incident age-related nuclear cataracts in the Beaver Dam Eye Study”, International journal of sports nutrition
  • Harman, 1956, “Aging: a theory based on free radical and radiation chemistry”,  Journal of Gerontology
  • Harman, 1972, “A biologic clock: the mitochondria?”,  Journal of the American Geriatrics Society
  • Glewwe P, 2001 “Early childhood nutrition and academic achievement: A longitudinal analysis”,  Journal of Public Economics
  • Whitley JR, 1951,  “Effect of diet on maze learning in second generation rats; folic acid deficiency”,  International journal of nutrition
  • Di Pasquale and Mauro G., 2008, "Utilization of Proteins in Energy Metabolism", International journal of sports nutrition
  • Jiang, Q and Christen, 2001, “gamma-tocopherol, the major form of vitamin E in the US diet, deserves more attention.”, The American journal of clinical nutrition
  • Helzlsouer, Comstock, 2000, “Association Between alpha-Tocopherol, gamma-Tocopherol, Selenium, and Subsequent Prostate Cancer”, Journal of the National Cancer Institute
  • Moriartycraige and S Adkison, 2005, “Antioxidant Supplements Prevent Oxidation of Cysteine/Cystine Redox in Patients With Age-Related Macular Degeneration”,  American Journal of Ophthalmology
  • Gladyshev VN and Hatfield DL 1999, “Selenocysteine-containing proteins in mammals”,  Journal of Biomedical Science