(1) Background: Sleep quality is closely related to the physical and mental health of college students. The objectives of this study were to obtain data on the sleep quality of university students and to investigate the relationship between intestinal flora and the improvement in sleep quality through exercise intervention. (2) Methods: Here, 11 university students with a body mass index (BMI) ≤ 18 and Pittsburgh Sleep Quality Index (PSQI) ≥ 7 were selected as experimental subjects, and another 11 healthy people were recruited as control subjects. The experimental group and control group were each intervened with exercise for 8 weeks. We used 16SrDNA sequencing technology to analyze the variations of the intestinal flora and the relation of the variations and sleep quality improvement between the experimental group and the control group before and after the exercise intervention. (3) Results: The differences in gut flora composition between people with sleep disorders and healthy people were statistically significant (p < 0.05). Before and after the exercise intervention, the differences were also statistically significant (p < 0.05) in people with sleep disorders. The sleep-disordered population had a larger proportion compared with the healthy population (p < 0.05). Blautia and Eubacterium hallii were microbe markers in the sleep-disordered population before and after the exercise intervention, while there was no microbe marker found in the healthy population. (4) Conclusions: The increase in Blautia and Eubacterium hallii, and the decrease in Agathobacter are associated with healthy sleep. Gut flora may be related to sleep disorders. Exercise intervention can improve sleep quality while changing the diversity of the gut flora, and exercise intervention targeting the gut flora is a new concept for preventing and treating sleep disorders.
Keywords: exercise intervention; intestinal flora; microbiota composition; sleep quality.