Xuxi Zhang

Finally, sensitivity analyses were performed where all analyses were repeated using the participants in the control group only; we found similar results. All analyses were performed with SPSS version 23.0 (IBM SPSS Statistics for Windows, Armonk, NY: IBM Corp). The level of significance was P ‐ value<0.05. RESULTS Baseline characteristics of participants Table 1 shows the general characteristics of the study population at baseline. The mean age of participants was 79.6 (SD = 5.5) years and 61.1% were female. Compared with participants who undertook moderate PA with a regular frequency, participants with a low frequency of moderate PA were older ( P < .001), were more often female ( P < .001), had less often completed tertiary level education ( P < .001), were less often at risk for alcohol use ( P < .001) and more often suffered from multi ‐ morbidity ( P = 0.004). Figure 1 shows the frequency of moderate PA of participants at baseline and follow ‐ up as well as change in frequency of moderate PA. At baseline, 1272 participants reported undertaking moderate PA with a regular frequency. Of these, 1020 (58.8% of the study population) continued this regular frequency after 12 months of follow ‐ up and in 252 (14.5%) had decreased their exercise to low frequency. Of the 463 participants who undertook moderate PA with a low frequency at baseline, 302 (17.4%) continued this low frequency after 12 months of follow ‐ up, and 161 (9.3%) had increased their exercise to a regular frequency. Figure 1 Frequency of moderate physical activity of participants 56 Chapter 3