The effects of Pulsed Electromagnetic Field (PEMF) on muscular strength, functional performance and depressive symptoms in elderly sarcopenia: a short-term intervention

Abstract

Despite the benefits of resistance training in mitigating sarcopenia, adherence among frail older adults is often limited by osteoarticular pain, comorbidities, and logistical barriers. Pulsed electromagnetic field (PEMF) therapy has emerged as a potential alternative. However, evidence regarding its effects on functional and psychological parameters remains scarce. Objectives: To assess the effects of 12 PEMF therapy sessions on knee extensor strength and functional performance (Timed Up and Go test—TUG) in older adults with sarcopenia. Secondary outcomes included changes in calf circumference (CC), SARC-F + CC scores, and depressive symptoms. Methods: A controlled, non-randomized experimental design was employed, with a pre-intervention control group serving as a baseline reference (PEMF group: n = 25; control group: n = 16). Participants received 12 PEMF therapy sessions (three times per week) targeting the quadriceps and gastrocnemius muscles. Outcomes were measured using knee-extension dynamometry, TUG, CC, SARC-F + CC, and the Yesavage Geriatric Depression Scale. Statistical analyses included ANCOVA, with baseline values as covariates. Results: Significant improvements were observed in knee-extension strength, which increased from 13.05 ± 4.8 kgf to 18.56 ± 8 kgf (p < 0.001); TUG test time improved from 23.1 ± 14.4 to 18.7 ± 10 s (p = 0.048); SARC-F + CC scores decreased from 11.6 ± 8.2 to 6.5 ± 7.6 (p < 0.001), though the interaction effect with time was not significant (p = 0.252). No statistically significant changes were observed in CC, which increased from 34.0 ± 4.0 cm to 36.0 ± 3.9 cm following the intervention (p = 0.548). Yesavage Geriatric Depression Scale scores improved significantly (7.9 ± 2.4 to 5.4 ± 1.7, p = 0.0013). Conclusions: PEMF therapy significantly improved lower-limb muscle strength and functional mobility in elderly individuals with sarcopenia. Additionally, depressive symptoms were significantly reduced. However, no significant changes were observed in CC or SARC-F + CC.