Effects of Calcium-Regulating Pulsed Electromagnetic Fields Plus Respiratory Muscle Training on Poststroke...

Stroke is frequently accompanied by respiratory dysfunction, which limits ventilatory reserve and may hinder functional recovery. Respiratory muscle training (RMT) can improve selected ventilatory indices, but overall benefits remain modest. This pilot trial aimed to evaluate the clinical effects of calcium-regulating pulsed electromagnetic fields (Ca-R-PEMF) combined with RMT on poststroke respiratory function.

This single-center, prospective, double-blind pilot trial was conducted at Yongsen Hospital of China Medical University, China, from July to December 2025. Thirty patients were randomly assigned to standard rehabilitation plus sham stimulation (control group), standard rehabilitation plus sham stimulation and RMT (RMT group), or standard rehabilitation plus Ca-R-PEMF stimulation and RMT (Ca-R-PEMF+RMT group; n=10 per group). The intervention lasted 4 weeks, RMT was administered 5 sessions per week (20 minutes/session), and Ca-R-PEMF stimulation was administered 2 sessions per week (15 minutes/session). Outcome measures were recorded at baseline and after 4 weeks of intervention. The primary outcome was the change rate in forced vital capacity. Secondary outcomes included forced expiratory volume in 1 second (FEV₁), FEV₁/forced vital capacity, peak expiratory flow, inspiratory capacity, and vital capacity.

A total of 27 participants completed the 4-week follow-up (n=9 per group), and baseline characteristics were comparable across groups. The change rate in forced vital capacity differed significantly among groups (P<0.01; η²=0.47). Ca-R-PEMF+RMT showed greater improvement than both control and RMT, whereas the difference between control and RMT was not significant. For secondary outcomes, overall between-group differences were significant for FEV₁ (P<0.01; η²=0.39) and peak expiratory flow (P<0.01; η²=0.41). Ca-R-PEMF+RMT was superior to control for both outcomes, and RMT was superior to control for FEV₁. No significant between-group differences were observed for the change rates in the FEV₁/forced vital capacity, inspiratory capacity, or vital capacity. No adverse events related to the treatment were reported.

In this pilot trial, Ca-R-PEMF combined with RMT was feasible and appeared safe in patients with stroke and respiratory dysfunction. Following 4 weeks of training, Ca-R-PEMF+RMT showed more favorable signals of improvement in selected pulmonary ventilatory indices than standard rehabilitation alone and RMT alone, suggesting its potential value as a combined rehabilitation strategy.

URL: https://www.chictr.org.cn; Unique identifier: ChiCTR2300078947.