Oral Administration of Hot Water Extracts of Chlorella vulgaris Increases Physical Stamina in Mice

Background/Aims: A unicellular algae, Chlorella vulgaris, was used as a biological response modifier. Although hot water extracts of C. vulgaris (CVE) are thought to augment immune responses, the effect of CVE on fatigue and physical stamina has not been studied. Methods: In the present study, we investigated the effect of CVE on forced swimming test and blood biochemical parameters related to fatigue, blood urea nitrogen (BUN), creatine kinase (CK), lactic dehydrogenase (LDH), glucose (Glc), and total protein (TP). CVE (0.05-0.15 g/kg/day) was orally administered to mice. Results: After 7 days, the immobility time was decreased in the 0.1- and 0.15-g/kg CVE-treated groups (179 ± 8.3 and 175 ± 2.1 s) in comparison with the control group (223 ± 5.4 s). In addition, the contents of BUN, CK, and LDH in the blood serum were decreased in the CVE-fed group. However, they had no effect on the elevation of Glc and TP level. Conclusions: The results predict a potential benefit of CVE for enhancing immune function and improving physical stamina.