The aim of the current study was to investigate the outcomes in a rat model of an acute swimming exercise induced oxidative stress in brain, kidney, liver, skeletal and cardiac muscles using supplementation with crocin. Rats were divided into the eight groups; Normal Control (NC: Untreated and did not swim), Crocin Control (CC: Received crocin and did not swim), Exercise-1 (E-1: Untreated and swam), Exercise-24 (E-24: Untreated and swam), Exercise-48 (E-48: Untreated and swam), Exercise+Crocin-1 (EC-1: Received crocin and swam), Exercise+Crocin-24 (EC-24: Received crocin and swam), Exercise+Crocin-48 (EC-48: Received crocin and swam). The malondialdehyde (MDA) and xanthine oxidase (XO) enzymes levels increased after swimming in untreated and crocin treated groups, but there was a lower increase in crocin treated groups. The highest MDA levels in all tissues were observed in E-1 compared to all other groups. There were significant differences between control and exercise groups in MDA levels of tissues (p < 0.001). In contrast, there were significant differences between control and exercise groups in glutathione (GSH) levels of tissues. In addition, the crocin supplementation significantly increased GSH levels and decreased MDA and XO enzyme levels when compared to untreated exercise groups. Crocin can protect the tissues against exercise induced oxidative stress by enhancing antioxidant activity (Tab. 3, Fig. 1, Ref. 37). Text in PDF www.elis.sk.