Perimenopause, a transitional phase leading up to menopause, is a critical period in a woman's life characterized by significant hormonal fluctuations1. This stage typically commences in women's mid-to-late 40s and can last for several years. The hallmark of perimenopause is a decline in estrogen levels, a hormone pivotal to various physiological functions, including the regulation of the menstrual cycle and the maintenance of bone density2. The decrease in estrogen during perimenopause profoundly affects bone health. Estrogen plays a crucial role in bone remodeling – a process where old bone tissue is replaced by new bone tissue. Reduced estrogen levels disrupt this balance, leading to increased bone resorption (breakdown) over bone formation. This imbalance results in a gradual decrease in bone mineral density (BMD), a critical factor determining bone strength and resilience3. As BMD decreases, the structural integrity of bones is compromised, significantly elevating the risk of osteoporosis, a condition characterized by fragile and brittle bones. Osteoporosis, a silent yet debilitating disease, poses a significant health risk, particularly for postmenopausal women4. It increases the likelihood of fractures, which can lead to decreased mobility, chronic pain, and even life-threatening complications. Given the aging global population and the associated increase in osteoporotic fractures, there is a pressing need to explore and establish effective interventions. Such interventions are essential not only in slowing down the progression of bone density loss but also in enhancing overall skeletal health during this vulnerable phase of a woman's life. Recognizing and addressing the impact of perimenopause on bone health is, therefore, crucial for improving the quality of life and long-term health outcomes for women globally.

Tai Chi Rouli Ball, an innovative and integrative physical activity, merges the principles of Tai Chi with the dynamic movements of Rouli Ball, a traditional Chinese sport5. This activity, which encapsulates the essence of Chinese martial arts and embodies the philosophy of Yin and Yang, has been gaining momentum and recognition worldwide6. Characterized by its gentle, flowing movements, Tai Chi Rouli Ball is not only a form of physical exercise but also a meditative practice that promotes mental well-being7. Previous studies and theoretical frameworks have illuminated the multifaceted benefits of Tai Chi Rouli Ball. At its core, this practice enhances physical fitness, improves balance and flexibility, and fosters mind-body harmony8. Specifically, in the context of bone health, Tai Chi Rouli Ball has shown promise. The weight-bearing nature of its movements, combined with the balance and coordination required, suggests potential benefits in maintaining and improving BMD. Moreover, the meditative aspects of Tai Chi Rouli Ball may contribute to the reduction of stress-related hormones, which can negatively impact bone health. Despite these theoretical advantages, empirical research specifically targeting the effects of Tai Chi Rouli Ball on bone health in perimenopausal women remains limited.

The primary aim of this study is to rigorously investigate the effects of Tai Chi Rouli Ball, a unique physical activity blending elements of Tai Chi and Rouli Ball, on bone health in perimenopausal women. Specifically, the study focuses on assessing changes in bone mineral content (BMC), BMD, and various bone metabolism indicators, thereby providing a comprehensive understanding of the potential benefits of this exercise form. Key measurements are taken before and after the intervention to assess changes in BMC, BMD, and bone metabolism markers, such as calcium, phosphorus, and magnesium levels, along with hormone levels like estrogen and testosterone.