مرکز منطقه ای اطلاع رساني علوم و فناوري - اثر دريافت ماست پروبيوتيك بر عملكرد ورزشي، علايم عفونت هاي تنفسي و ناراحتي هاي گوارشي دختران نوجوان شناگر استقامتي

چكيده لاتين :

Background and Objectives: Severe and intense exercises by athletes will increase the risks of infectious diseases of the upper respiratory system and digestive system disturbances, resulting in chronic exhaustion and reduced efficiency. Very few studies have been made on the effects of probiotics on athletesʹ immunity system and work efficiency during training and in tournaments. This study was carried out to determine the effects of consuming probiotic yogurt on performance, respiratory infections, and digestive disorders of Tehrani juvenile athlete girls involved in intensive swimming during 2009. Methods: This was a randomized controlled trial. It included 46 endurance girl swimmers with a mean age, weight, and height of 13.8±1.8 years, 48.6±7.5 kg, and 159 ±5.6 cm, respectively, participating in 400 and 800-m crawl swimming tournaments in 2009. They were randomly assigned to two groups, receiving daily for 8 weeks, either 400 ml probiotic yogurt (intervention group) or ordinary yogurt (control group). All the subjects were asked to record daily, on a questionnaire, digestive symptoms; respiratory infections, exercise performed (in meters), intake of medicines, and the exact quantity of yogurt consumed. At the beginning and at the end of the eighth week the 400-m free swimming record was recorded and the Harvard Step test was employed to measure VC^max. The data were analyzed using the SPSSn software. Results: The average changes in the records of the intervention and control group were 3.9 and 0.5 seconds, respectively (P = 0.22). On the other hand, the change in VOimax in the intervened group was 0.56, and in the control group 0.01, ml/kgʹ1.min"1, in both cases statistically significant (p=0.02). Analysis of the data also showed that, on the average, the intervention group complained of dyspnea, a symptom of respiratory infection, for 2.4 days, the control value being 4.3 days (p=0.024); the corresponding figures for ear pain, another symptom of respiratory infection, were 0.52 and 1.6 days (p=0.008). The average number of episodes of respiratory infection in the intervention group was one day, which was statistically fewer than that in the control group (1.4), the difference being statistically significant (p=0.009). In addition, the average number of episodes of digestive disorders was 0.9 in the intervention group and 0.6 in the controls (p=0.05). After 8 weeks of intervention, no significant difference was found between the 2 groups with regard to the average duration of respiratory infection or digestive disorders. Conclusion: Consumption of probiotic yogurt results in a reduction in the number of episodes of respiratory infections and in duration of some of its symptoms as dyspnea and ear pain; the reduction in digestive symptoms did not reach statistical significance. It also brought about a significant improvement in VC^max and a non-significant decline in the record of 400m crawl swimming. Further studies on the effects of probiotics on athletesʹ nutritional health and performance in other sports are recommended.