How Athletes Can Protect Themselves Against the Flu

Although exercise is beneficial for numerous reasons, it can put athletes at risk for the flu and common cold, since it has been linked with depression of immune system functions.

Many athletes also experience stress from strenuous exercise and a lack of nutrients during dieting and vigorous training.

A recent study reported that psychological stress, lack of sleep, and environmental changes can also cause athletes to become ill. Additionally, increased respiration during exercise gives airborne viruses and bacteria a paradoxical opportunity for infection.

The easiest way for athletes to maintain a healthy immune system is to ensure balanced nutritional intake—specifically adequate protein and micronutrients. However, some nutrients are more important than others.

Researchers recently determined that vitamin D is critical to immune function. Studies have demonstrated that athletes can experience vitamin D deficiency especially during winter months. Therefore, supplementation of 1,000 IU of vitamin D daily from autumn to spring may be considered for athletes.

To limit metabolic stress from vigorous exercise, athletes should drink carbohydrates (30 g/hr to 60 g/hr) during exercise. By keeping glucose levels elevated, stress hormones like adrenaline and cortisol are less likely to be produced.

Antioxidants are often studied for immune-boosting properties, as well. Although mega-doses of vitamin C remain controversial for everyday use, its use in marathon runners has demonstrated immune benefit.

A recent meta-analysis indicated that a daily probiotic containing lactobacillus and bifidobacterium can decrease the duration and severity of respiratory infections in athletes.

Plant polyphenol offers many antioxidant, anti-inflammatory, and anti-pathogenic properties. Eating ample fruits and vegetable will provide athletes with plant phenols, as well as other nutrients.

Colostrum, which is produced by the mammary gland of a cow for a short time after giving birth, has multiple immune protective substances and is marketed as a liquid and powder. Much like probiotics, it has been shown to decrease the number of days and severity of respiratory infections in athletes.

By maintaining a balanced diet and paying close attention to nutritional intake, athletes can help keep their immune system strong and prevent respiratory infections and the flu.

These study findings were published ahead of advance online publication in Immunology and Cell Biology.