In a review of studies on probiotics and athletic performance, researchers noted while probiotics don’t directly affect athletic performance, probiotics help athletes avoid becoming ill from over-exertion and increase the chances that athletes will stay healthy.
Doctors found consistent evidence that athletes who take probiotics recover faster from fatigue, stay healthier overall, including catching fewer colds, and avoid stomach and intestinal upset compared to athletes who do not take probiotics.
In an athletic fatigue study, researchers noted that when athletes over-train, their immune systems respond poorly, making them susceptible to viruses, especially Epstein Barr Virus (EBV). EBV causes mononucleosis and may cause chronic fatigue syndrome.
In this study, doctors took saliva samples from eight fatigued athletes before and one month after taking L. acidophilus probiotics capsules. Before treatment, five athletes tested positive for EBV. After treatment, one tested positive.
Researchers also found that the type of white blood cell (CD4) that responds to infection was malfunctioning before treatment and functioned normally afterward.
Journal of the International Society of Sports Nutrition; December 2008, Electronic Pre-publication.