The Effect of Dynamic Neuromuscular Stabilization Exercises Combined with Visual Mirror Feedback Compared to Non-Mirror Feedback Training on Respiratory Function in Patients with Parkinson's Disease: A Secondary Analysis of a Randomized Controlled Trial

Document Type : Original Articles

Authors
Mohaddeseh Assari 1
Gholamali Ghasemi 2
Morteza Sadeghi 3
Ahmad Chitsaz 4
1 MSc Student, Department of Sports Injuries and Corrective Exercises, School of Sports Sciences, University of Isfahan, Isfahan, Iran
2 Professor, Department of Sports Injuries and Corrective Exercises, School of Sports Sciences, University of Isfahan, Isfahan, Iran
3 Assisstant Professor, Department of Sports Injuries and Corrective Exercises, School of Sports Sciences, University of Isfahan, Isfahan, Iran
4 Professor, Department of Neurology, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran
10.48305/jrrs.2026.46277.1143
Abstract
Introduction: Parkinson's disease (PD) can impair respiratory muscle strength and pulmonary function, contributing to reduced cough effectiveness, reduced speech volume, and reduced exercise tolerance. Dynamic Neuromuscular Stabilization (DNS) improves trunk and core control, potentially enhancing respiratory mechanics. Mirror visual feedback (MVF) has been shown to improve sensorimotor integration and body awareness, but its effect on respiratory outcomes in PD is unknown. This secondary analysis compared the effects of an 8-week DNS program, performed with or without MVF, on spirometric parameters in patients with PD.
Materials and Methods: In a randomized controlled trial, 35 adults with idiopathic PD (Hoehn & Yahr I–III) completed an 8‑week DNS training program (3 sessions/week, 45–60 min/session), either in front of a full‑length mirror (DNS+MVF, n = 18) or without a mirror (DNS‑only, n = 17). For this secondary analysis, spirometric assessments were performed at baseline and post-intervention, including forced vital capacity (FVC), forced expiratory volume in 1 second (FEV1), FEV1/FVC ratio, FEV₁/VCmax%, forced expiratory flow at 25–75% (FEF₂₅‑₇₅), and peak expiratory flow (PEF). Data from 34 participants (17 per group) with complete respiratory measurements were analyzed using a two-way repeated-measures ANOVA and tests of between-subject effects.
Results: Both groups showed significant within-group improvements over time in all spirometric parameters (all P < 0.010). However, the DNS+MVF group demonstrated significantly larger improvements than the DNS‑only group for FVC (Group  ×  Time interaction: F  =  72.03, P  <  0.001, partial η²  =  0.783), FEV₁ (F  =  29.19, P  <  0.001, partial η²  =  0.711), FEF₂₅‑₇₅ (F  =  6.13, P  =  0.022, partial η²  =  0.235), and PEF (F  =  6.42, P  =  0.020, partial η²  =  0.243). Between‑subject effects also favored the mirror group for FVC (P  =  0.008) and PEF (P  =  0.043).
Conclusion: The addition of mirror visual feedback provided a statistically significant additive benefit for respiration. These findings suggest that mirror‑augmented DNS may be a simple, low‑cost strategy to enhance respiratory function in PD. Further studies with larger samples and longer follow‑up are warranted.
Keywords
Parkinson&rsquo
s disease
Dynamic neuromuscular stabilization
Mirror visual feedback
Respiratory function
Spirometry
Pulmonary rehabilitation
Subjects
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