The effects of rTMS combined with blood flow restriction low-intensity resistance training on skeletal muscle mass, strength, and physical function in postmenopausal women: a single-blind randomized controlled trial protocol

Background: Skeletal muscle serves as the primary source of power for body movement. Due to the transition of menopause, older women experience a relatively faster decline in skeletal muscle mass and function, making them more susceptible to age-related skeletal muscle disorders such as sarcopenia, which can lead to adverse outcomes such as falls, fractures, disability, or even death. Blood flow restriction low-intensity resistance training (LI-BFRT) can effectively enhance muscle strength and promote skeletal muscle growth, while repetitive transcranial magnetic stimulation (rTMS) has previously been shown to improve motor cortex excitability and limb motor function. We describe a trial protocol to investigate the effects of a 12-week intervention combining rTMS with LI-BFRT on skeletal muscle mass and physical function in community-dwelling postmenopausal women. Methods: This single-blind, randomized controlled trial will recruit 54 eligible community-dwelling postmenopausal women aged 50-65 years who have been naturally postmenopausal for 1 year or more. Participants will be randomly assigned in a 1:1:1 ratio to the rTMS combined with the blood flow restriction low-intensity resistance training group (rTMS + LI-BFRT), the blood flow restriction low-intensity resistance training group (LI-BFRT), and the control group, respectively, for a 12-week intervention period. Participants will undergo assessments at baseline (Week 0), immediately after the intervention (Week 12), and long-term follow-up (Week 24). The primary outcomes include lower limb muscle mass, muscle strength in both the upper and lower limbs; secondary outcomes include body composition, physical function (5-time sit-to-stand test, 30-second stand test, timed up-and-go test, 30-second arm curl test), motor cortex excitability, and clinical blood markers related to neural and muscular function. Discussion: We have combined central and peripheral motor activation methods for the first time, attempting to use BFRT in combination with rTMS intervention to recruit more motor units by increasing motor cortex excitability, thereby enhancing skeletal muscle motor ability under BFRT and examining the intervention effects on skeletal muscle mass and strength in postmenopausal women. This will provide a new paradigm for healthy intervention in the skeletal muscles of postmenopausal women. Clinical Trial Registration: http://www.chictr.org.cn, Chinese Clinical Trial Registry ChiCTR2400086697.