Sports Performance and Vitamin Supplementation: Is it Necessary?

According to many researchers, athlete’s needs for vitamin's may be higher than the general population. The reason being, intense physical activity increases energy and oxygen demand. Of course, athlete’s needs will depend upon the type of sport, training intensity and environmental conditions that the athlete is to undertake or exposed too.

Several studies have disputed as to whether mult-ivitamin supplementation is necessary for athletic performance. It has been suggested that specific nutrients may be required to buffer oxidative muscle and bone damage, as high energy expenditure increases free radical production, inducing fatigue. That being said, this article will examine current knowledge and recommendations for athletes regarding one group of vitamins, B group vitamins.

B group vitamins are water soluble vitamins that play a major role in the body, of particular note, energy production. In total, there are 8 B vitamins, in which the body has a limited capacity to store (excluding Vitamin B 12 and Folate (Vitamin B9). For this reason, it is important that athletes regularly consume foods that are high in a range of B vitamins. However, B vitamins are easily destroyed by both cooking and alcohol. Hence, supplementation may assist in acquiring the recommended daily amounts of B group vitamins.

Vitamin B-1 (Thiamine): Is vital to the breakdown of carbohydrates in the body for energy. It is also required for all nerve and muscle cells, allowing our hearts, brains and digestion to work at an optimal level. It is suggested that the recommended daily thiamine intake of 1.1-1.2 mg daily may be insufficient for athletes. For example, increased physical activity increases the need for Vitamin-B1. Generally, it is necessary for each 1000-calories we consume to consume a minimum of 0.5 mg of thiamine (1 cup of raw green beans). Whilst, the average healthy individual may consume 2000-calories per day, athlete's can consume between 3000-5500 calories daily. Due to thiamine's role in energy production it was assumed that thiamine deficiency would inhibit sports performance, by inhibiting the breakdown of carbohydrates and increasing lactic acid accumulation. This has been found to be true, with athlete's who fail to consume adequate amounts of thiamine negatively influencing their performance. Moreover, several studies have shown that athlete's consuming 100 mg/day of thiamine significantly reduced their level of fatigue after short workouts, whilst Olympic skeet shooters experienced improved neurological control of motor movement in shooting after supplementation.

B1 Foods: whole grain cereals, legumes, nuts, liver.

Vitamin B2 (Riboflavin): Is vital to the breakdown of amino acids and essential to energy production. Due to increasing energy consumption and its incorporation into helping form new muscle, athlete's require greater amounts of this vitamin. Several studies suggest that endurance athlete's are in need of increased amounts of riboflavin, as a result of the protein-lost during heavy training, and for recovery and repair following endurance events. Moreover, there is a greater need of riboflavin for female athlete's involved in physical activity, especially when weight-loss is a priority. The recommendation for athlete's is 0.6 mg per 1000 calories.

B2 Foods: Milk, eggs, liver, chicken, dark green vegetables, nuts and mushrooms.

Vitamin B3: Is vital to the the breakdown of carbohydrates, proteins and fats for energy production. Most individual athlete's meet the defined recommendations of 12-14 mg daily. However, the International Olympic Academy approves at least a 10 percent increase in niacin intake, in order to increase energy use and the physical strength of athletes who engage in intense exercise. It is important to know that excessive amounts of niacin can contribute to poor sports performance. For example, excessive amounts of niacin can inhibit the breakdown of fats and in turn reduce energy to the muscles during exercise. This can lead to increased use of carbohydrates as the main energy source. However, with reserves of glucose and glycogen in the muscles being limited, there is an early exhaustion of the reserves and as a onsequence endurance is reduced.

B3 Foods: milk, eggs, chicken, fish, whole grains.

Vitamin B5 (Pantothenic acid): Is vital to the breakdown of carbohydrates, fats and proteins as well as being involved in the formation of cholesterol, haemoglobin and myoglobin (oxygen and iron binding protein in muscle). Supplements typically contain between 50-105 mg, which is between 10 and 21 times higher than the recommended dietary intake, yet without reported toxic effects. There are some researchers that view this amont as excessive and not recommended. Despite recent studies showing that road cyclists, for example, absorb Vitamin B5 through supplementation more efficiently than they did through the consumption of foods containing Vitamin B5,  it has not been shown to alter exercise  metabolism or exercise performance. Nonetheless, if an athlete is not consuming the recommended daily intake, supplementation is a wise option. Recently, the International Journal of Sports Nutrition and Exercise Metabolism identified that 54.5 percent of elite canadian female soccer players did not consume the recommended daily intake of Vitamin B5.

B5 Foods: vegetables, liver, kidneys, eggs.

Vitamin B6 (Pyridoxine): Is vital to the breakdown of amino acids and proteins, necessary for the breakdown of glycogen in the muscle to yield energy, important in maintaining the health of our nervous system and in muscle relaxation. Athlete's require additional Vitamin B6 for several reasons, these include: increased protein intake requires an increase in Vitamin B6 consumption, particularly if the athlete is consuming purified protein supplements; Because Vitamin B6 it absolutely necessary for muscular activity during exercise, if there is not enough to convert glycogen into energy, muscular activity will be grossly inhibited; Vitamin B6 plays a role in the release of human growth hormone, which increases muscle growth and has a positive influence on aerobic performance and resistance training.  The international Olympic Academy has set an upper limit of 100 mg daily.

B6 Foods: liver, whole grains, eggs, fish, fruits and vegetables and seeds.

Vitamin B7 (Biotin): Is responsible for the formation of fatty acids and glycogen as well as the breaking down of amino acids. Alongside the mineral/metal magnesium it is involved in the conversion of amino acids into carbohydrate for energy. There is a possibility that biotin has an effect on physical actiivity through its involvement in energy production, however, there are no studies specifically on biotin supplementation and athletic performance.

B7 Foods: egg yolk, liver, kidney, mushrooms, dark green leafy vegetables, tomatoes.

Vitamin B9 (Folate): Is vital in the formation of red blood cells alongside Vitamin B12, and in the prevention of anaemia. Of all the B vitamins, folate is the one vitamin that appears to be consistently low in the diets of female athletes. The recommeded daily intake stands at 400 micrograms per day, however the American Dieticians Associations recently reported that 53 percent of female athletes consume less than 400 micrograms daily. There is reason to suggest that the use of folate supplementation is of benefit to athletes involved in impact sports e.g. rugby league, rugby union. The reason being, folate plays a role in increasing the rate at which damaged tisssue regenerates and heals. Moreover, it may benefit road cyclists and marathon runners, at altitude, as folate can increase red blood cell production.

Vitamin B9: green leafy vegetables, whole grains, oranges, banana, lentils, seeds, wheat germ and liver.

Vitamin B12 (Cobalamin): Perhaps the  most frequently discussed B vitamin. It is vital to every cell function and particularly important to the formation of our DNA. The Journal of Clinical Nutrition found that 45 percent of female and 30 percent of male Triathletes did not consume the recommended daily intake of Vitamin B12. Moreover, the American Dietiticans Association found that over 33 percent of trained cyclists consumed less than the recommended daily intake of Vitamin B12.  This is concerning when Vitamin B12 is involved in red blood cell formation, the breakdown of folic acid, the development and maintenance of our nervous system and the breakdown of fats to protect our cells. There are known cases of Vitamin B12 misuse when athletes self-injected large doses of the vitamin prior to competition. However, there is little evidence to suggest that excessive doses of Vitamin B12 enhanced athletic performance. Supplementation is highly recommended in older athletes, as well as athletes with inherited Vitamin B12 malabsorption.

B12 Foods: Meat, fish, shellfish, chicken, eggs, milk and cheese.

In short, B vitamins are essential to optimal health, whether you are an athlete or not. That being said, there is an increased need for athletes to consume B vitamins at a higher dose than that of the general population. Supplementation can assist in allowing athletes to meet the recommended daily intake of B vitamins if dietary intake is inadequate.

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