Introduction: Plyometric exercises are used to improve strength and explosive power in athletes, but it is associated with muscle soreness and severe muscle damage due to eccentric contraction. It is believed that a combination of carbohydrate and protein could inhibit exercise-induced muscle damage due to the changes in protein metabolism.  Accordingly, the purpose of this study was to identify the effects of 500 ml low-fat milk on serum level muscle damage indices following one session of plyometric exercise. 

Materials & methods: The all undergraduate students of Birjand university were considered as a society population and then 20 persons were randomly divided into two equal groups (n=10) including supplementation and placebo groups. The supplementation group carried out 30 minutes of plyometric training (average of 210 movements) then immediately they consumed 500 ml low-fat milk. The placebo group received the same amount of water and also they performed similar protocol of plyometric exercise. Creatine kinase (CK) and lactate dehydrogenase (LDH) enzymes were measured by photometry method.  The data were analyzed by the Kolmogorov-Smirnov normality test, classical student t-tests, ANOVA and Bonferroni also were used for the detection of significant differences between groups by means of SPSS-19.

Findings: The serum level of LDH (p=0.03) and CK (p=0.006) during the 4 and 24 hours after the plyometric exercise were significantly lower in supplementation group than placebo respectively.

Discussion & Conclusions: Consumption of low-fat milk immediately after a plyometric exercise could induce faster cleaning of muscle damage indices but its influence on LDH enzyme may be established in a shorter time interval.