Researchers at Oregon State University found that athletes who lack B-vitamins have reduced high-intensity exercise performance and are less able to repair damaged muscles or build muscle mass than their peers who eat a diet rich with B-vitamins. The study results were published in the International Journal of Sport Nutrition and Exercise Metabolism.
They found that even a small B-vitamin deficiency can result in reduced performance and recovery. Individual B-vitamin requirements vary and may depend upon the type and intensity of exercise, the amount of nutrients lost through sweat, and urine, and individual differences in diet.
According to the researchers, the USRDA (United States Recommended Daily Allowance)for B-vitamin intake may be inadequate for athletes.
Those most at risk for the B-vitamin deficiencies include athletes who are limiting calories or have specialized, consistent or restricted eating plans.
You get B-vitamins from whole and enriched grains, dark green vegetables, nuts, and many animal and dairy products. The study authors stated that based upon the available literature on this topic, exercise may increase an athlete's requirement for riboflavin and vitamin B-6, however, the data for folate and vitamin B-12 are limited. They also recommend that athletes who have poor or restricted diets should consider supplementing with a multivitamin/mineral supplement. However, it is a good idea to talk with your doctor or pharmacist prior to adding any multi-vitamins or supplements to your diet.

