The purpose of this study was to investigate moderate endurance exercise-induced changes in oxidative stress in different phases of the menstrual cycle. We used saliva samples which can be collected non-invasively. The resting oxidative stress levels determined by oxidation-reduction potential (ORP) were significantly higher in the menstrual phase than the follicular and luteal phases. The ORP significantly increased 30 minutes after exercise started and at the end of the 60 minute exercise session in the follicular phase. The menstrual cycle may affect oxidative stress levels at rest among young women, whereas moderate endurance exercise is likely to increase oxidative stress in the follicular phase.

We analyzed the relation between subjective fatigue by hard exercise and stress hormone and cytokine data. The subjects are eight healthy men who had exercise experience. In this experiment, hard exercise was carried out in the first place. After two-hour rest, a performance test was carried out. The blood test was conducted 4 times (before exercise, after exercise, rest, and a performance test). Subjective fatigue was indicated using visual analogue scale (VAS). After the hard exercise and performance test, VAS increased and showed the significant difference. Lactic acid, adrenaline, noradrenaline, growth hormone, IL-6, and IL-8 increased after each exercise and showed the significant difference. Subjective fatigue and the value of lactic acid, and IL-6 showed significant positive correlations. These results suggest that lactic acid, and IL-6 may become an index of fatigue in this exertion model.