The primary goal of this study is to examine the effect of one-hour walking exercise on sleep quality in adults. The second goal of this study is to explore a feasible exercise method to promote sleep quality to all age groups, in order to improve sleep quality in overall population. The study attempts to unfold how the daily exercise, such as walking, benefits sleep quality. This study hypothesis that one-hour walking improves sleep quality in general population.

In order to test the hypothesis that walking exercise improves sleep quality in general population, the investigators conducted a randomized (case-control) cross-over trial. The targeted population is the physically and mentally healthy adults (18+). The health status was self-reported, the investigators did not organize physical and mental examination for participants in this study. The investigators recruited participants both online and off-line. The call-for-participants advertisement distributed in social media platforms such as Facebook, WeChat etc.

There were two groups in this study: walking group, and control group. The call-for-participants advertisement was distributed through online platforms and by posters. In the advertisement, all people were welcomed to participate, after receiving the applications, the investigators assessed the participant. In order to test the hypothesis that walking exercise improve sleep quality in general population, the investigators conducted a randomized (case-control) cross-over trial.

Participants can only be accepted after approval from the research team who performed the group discussion and evaluation of the sedentary behavior. If the participants meet the sedentary criteria, the participants would be informed the consent and terms and conditions to participate the study. Participants were randimzed into two groups by lottery (intervention and control group). The first phase intervention lasted for four weeks. At the beginning and at end of the intervention, the investigators assessed the sleep quality of participants by the Pittsburgh Sleep Quality Index (PSQI), Perceived Stress Scale (PSS) and Satisfaction With Life Scale (SWLS). The second phase was a wash period (4-week) and the third phase was a 4-week intervention. It has to be noted that at the beginning of the third phase, the participants in the two groups exchanged their role to receive active interventions. Participants in each group were coded by an autonomous number with characters.

Walking exercise was self-controlled and tracked by daily dairy and pedometers. All of the participants are obligated to record the start and end time of walking every day. And pedometers (mode: Omron HJ-112) were used for tracking walking steps including heart rate, calories and miles. For the ones who were in the control group, they had to keep sedentary lifestyle.

The participants had the responsibility to carry out the walking practice every day in the first and third phase. Every participant was counselled and gave their written informed consent before entering into the trial. The participation of this project was voluntary, unpaid. During the trial, all participants were free to quit the project with reasonable reasons, the investigators will not force anyone to continue the project if they cannot insist on. The investigators would inform the results of the first phase if the participant requests.

Inclusion Criteria:

• between 18-60 years old
• without physical or metal diseases

Exclusion Criteria:

• People who responded to join the study were screened either online or face-to-face by two principal questions: 1: Do you participate in any kind of regular exercise programs (weight-lifting, walking, running, swimming etc.)? 2. Are you involved in any physical or sport teams? If the respondent answered "Yes" to at least one of the questions, he/she would be excluded from the study because it could interfere with the effect of intervention.

There is not plan for making IPD available to other researchers, as it has been confirmed in the consent form. What we can share is the result of the whole intervention study and intervention process.