IntroductionMiddle age is usually defined as 40-60 years old (Singh & Singh, 2006;Truong, 2013). Even so, middle age is not only determined solely by physical age, but also seen as a product of biological, social, and psychological factors. Compared with men, women experience more age-related health changes (Sharifi et al., 2014), which include physical decline, changes in appearance, cognitive decline, problems of menopause, and occurrence of illness (Truong, 2013), in addition to changes in financial and social conditions due to retirement, increased burden of roles, loss of loved ones, and family separation (Vivian &Bicca, 2015;Sharifi et al., 2014). Many studies have shown that middle-aged women are at increased risk of developing mental health problems such as stress, anxiety, and depression (Singh & Singh, 2006;Wang et al., 2013). According to Wang et al. (2013) up to 38.7% of middle-aged women in Taiwan suffered from depression. According to Singh & Singh (2006) a high and worrying rate with 44% of middle-aged women in India suffers from depression. In a nine-year study in India, the proportion of middle-aged women showing signs of depression and anxiety was 86.7% and 88.9%, respectively (Bansal et al., 2015). In Vietnam, according to a survey by Tu Du Hospital, the rate of depression among women around menopause reached 38% (Huynh, 2015).From the results shown in these studies, it is essential for middle-aged women to take care of their mental health.There are many self-care measures for mental health, and relaxation is one of the measures that have a positive effect on the state of mental health of each person. Relaxation is a physical state of deep rest, a process of softening muscles, helping a person's nerves and mind to be relaxed and calm, and helping people to control stress and anxiety (Benson, cited by Martin, 2008;Nguyen, 2017). Through a number of studies on middle-aged and elderly people, it has been shown that proper relaxation in various forms can help people reduce anxiety, depression, restore both physical and mental health, encourage a more positive feeling about the self (Galvin và et al.