Effects Of Milk Intake Combined With Exercise On Upper Respiratory Tract Infection In Older Adults During Winter

BACKGROUND: This study aimed to evaluate the effects of milk intake combined with weekly-performed bowling exercise for 1 year on salivary immunoglobulin A (sIgA) levels and on the incidence of upper respiratory tract infection (URTI) in older adults.METHODS: A total of 36 healthy individuals (54-76 years old) were randomly divided into two groups; one consumed milk and the other consumed a sports drink during a bowling exercise (once a week, 2 games per day). The amount of dairy milk intake and symptoms of URTI were evaluated using questionnaires. Saliva was collected to measure the concentration of sIgA. Thirteen people (4 males and 9 females; milk group: N=5, sports drink group: N=8) completed the one-year experiment.RESULTS: The incidences of URTI were significantly fewer, and the severity of symptoms was significantly lower in the milk group than in the sports drink group (P<0.05). The concentration of sIgA in the sports drink group decreased significantly between the start period and winter (P<0.01). An inverse correlation was found between milk and dairy intake and the number of incidences and symptoms of URTI.CONCLUSIONS: This study suggests that milk intake combined with regular bowling exercise leads to suppression of the incidences and symptoms of URTI.