Anti-fatigue effects of green tea beverage concentrate in mice.

The anti-fatigue effects of green tea beverage concentrate in mice was studied by randomizing 240 Kunming mice to 4 groups, and oral gavage of distilled water(control group) or various doses of green tea beverage concentrate[133mg/(kg·bw), 665 mg/(kg·bw), 1995 mg/(kg·bw)] respectively, for consecutive 45 days. The loading swimming time, levels of lactate acid, serum urea, and liver glycogen were determined before and after swimming tests. Results showed that, compared with control group, administration of green tea beverage concentrate can significantly lengthen the swimming time (for low and medium dose groups, P0.01), reduce the lactate acid level(immediately after swimming for the low dose group (P0.05), 20 minutes after swimming for all dose groups (P0.05), and increased the content of liver glycogen( for medium dose group, P0.05), while no significant difference was found in serum urea level (P0.05).It was concluded that green tea beverage concentrate may have anti-fatigue effects in mice, with strongest effects seen in medium dose group.