The Influence of Walking at Different Times of Day on Blood Lipids and Inflammatory Markers
Condition: Coronary Artery Disease
MeSH terms: Coronary Artery Disease; Myocardial Ischemia; Coronary Disease
Study type: Interventional

Summary: 
      It has been well known that moderate and regular levels of physical activity has a favorable
      effect on many of the established risk factors related to coronary artery disease (CAD).
      Given that exercise in the morning has a greater potential for inducing sudden cardiac death
      and myocardial ischemia, it may be sensible for patients with CAD not to take exercise at
      this time. Our previous study indicated that the protective effect of exercise in the evening
      was greater than morning. However, which times of day to exercise could achieve the greatest
      improvements in lipids and inflammatory markers remains unclear. The purpose of the present
      study was to investigate the responses of lipid profiles and inflammatory markers to walking
      at different times of day in sedentary patients with CAD.
    

Detailed description: 
      According to the inclusion and exclusion criteria, 330 patients with CAD between the ages of
      40 and 80 years were recruited from the inpatient cardiology department of the First
      Affiliated Hospital of Nanjing Medical University. Informed consent was obtained from each
      participant after explaining the study protocols. Patients were randomly assigned to one of
      the three groups: control group (n=110), morning walking group (n=110) or evening walking
      group (n=110). The control group was requested to maintain their usual level of physical
      activity. Participants in both walking groups were requested to walk at the speed of 2.5
      miles/h for 30 min/day or more on at least 5 days/week for a period of 12 weeks. The protocol
      of exercise was identical, while the difference between the two groups was that one group was
      asked for walking in the morning and the other group walking in the evening. Each participant
      was telephoned at least once a week to ensure the adherence to the exercise program. Patients
      were called back every month to understand the information about walking and medication use.
      In the intervention groups, subjects whose compliance rate with their respectively walking
      program were less than 85% were excluded in the analysis. Additionally, all the participants
      were given an advice on quitting smoking and were provided with similar diets by a
      nutritionist, as to caloric intake and nutrients. Total cholesterol, triglycerides,
      high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, lipoprotein a,
      white blood cell count and platelet count, fibrinogen were measured before and after the
      intervention.

      The Kolmogorov-Smirnov test was used to check the normal distribution of all continuous
      variables. The values of normal distribution were expressed as mean±SD, and non-normal
      distribution data were presented as median (interquartile range). Baseline differences
      between groups were determined by one-way analysis of variance and chi-square analyses.
      Baseline and follow-up values within each group were compared using the paired t test.
      General linear models were used to adjust the differences in baseline values for dependent
      variables. And two-way ANOVA was used for determination of the improvements of lipids and
      inflammatory markers in three groups. The significance level was defined as P<0.05. All
      analyses were carried out using SPSS version 13.
    

Intervention name(s): walking
Intervention type(s): Behavioral
Intervention description(s): Participants in both walking groups were requested to walk at the speed of 2.5 miles/h for 30 min/day or more on at least 5 days/week for a period of 12 weeks.One group was asked to walk in the morning and the other group was asked to walk in the evening.
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: None (Open Label)
Primary purpose: Supportive Care
Keywords: coronary artery disease; walking; lipids; inflammatory markers; time of day