The sample size was calculated based on a qigong study of heart disease [12]. In this study, the participants were divided into two groups: the ‘qigong’ and ‘relaxing’ groups. After eight sessions, in the ‘qigong’ group, the mean change in STAI-1 was 8.82 and the standard deviation was 10.385, which is in accordance with a two-tailed, α error of 5% and power of 80% shown in the following equation.