Objective: The aim of this study was to investigate the impact of total soy saponins (TS) on the antioxidant capacity from the liver in rats exercised to exhaustion. Methods: A one-time exhausted treadmill exercise session was used. Sprague-Dawley rats were divided into four groups: a control group—animals receiving no TS and no exercise (NTSNE), animals receiving TS and no exercise group (TSNE), animals receiving no TS and exercised to exhaustion group (NTSE), and animals receiving TS and exercised to exhaustion group (TSE). The TSNE and TSE groups were fed TS at a dosage of 20 mg/kg body weight, once per day for two weeks. The NTSE group was given a placebo, and the NTSNE group was not given any treatment. The NTSE and TSE groups were exercised at speed of 30m/min on treadmill until exhausted. The exercise time were recorded when the rats became exhausted and the rats were then decapitated and anatomized immediately. A 10% homogenate of the liver tissue was prepared. The liver levels of superoxide dismutase (SOD), catalase (CAT), malondialdehyde (MDA), glutathione peroxidase (GSH-Px), glutathione reductase (GR), reduced glutathione (GSH), total antioxidant capacity (T-AOC), and serum alanine aminotransferase (serum ALT) levels were tested. Results: TS increased the exercise time by 20.62% (p<0.05). As compared with the NTSNE group, the SOD and GSH levels were increased whereas the MDA level decreased significantly in the TSNE group (p<0.05, p<0.01, p<0.05). As compared with the NTSE group, the SOD, CAT, GSH-Px, GSH and T-AOC levels increased significantly whereas the MDA level and the serum ALT activity decreased in the TSE group (p<0.05, p<0.05, p<0.05, p<0.05, p<0.05, p<0.05, p<0.01). Conclusions: TS can significantly improve the exercised rat’s antioxidant activity in their liver to varying degrees, decrease MDA and serum ALT levels, protect liver cell and liver functions, increase the exercise time and delay the occurrence of the fatigue.