Effect of Manual Therapy, Motor Control Exercise, and Inspiratory Muscle Training on Maximum Inspiratory Pressure and Postural Measures in Moderate Smokers: A Randomized Controlled Trial

Abstract Objective The aim of this study is to assess whether adding manual therapy to motor control exercises protocol with inspiratory muscle training (IMT) (combined intervention) resulted in a greater effect than IMT alone in enhancing maximum inspiratory pressure (MIP) in the short term. Methods This was a single-blind, randomized, controlled trial. Fifty-one healthy moderate smokers were randomized into 2 groups: (1) IMT and (2) combined intervention. All participants received 8 individual sessions, 2 per week during a 4-week period. The primary outcome (MIP) and the secondary outcome (pulmonary function, forward head posture, and thoracic kyphosis) were recorded at baseline and after the treatments. Results There were differences between groups in change score for MIP (mean, 23.8; 95% confidence interval [CI]: 16.48-31.12), forward head posture (−1.57; 95% CI: –2.79 to –0.35), and thoracic kyphosis (–0.92; 95% CI: –1.74 to –0.1). The combined intervention revealed statistically significant differences for MIP (mean, –34; 95% CI: –39.12 to –28.88) and for postural measures (forward head posture 2.31; 95% CI: 1.45-3.16; thoracic kyphosis, 1.39; 95% CI: 0.8-1.97), whereas the IMT was only observed for MIP (mean, –10.2; 95% CI: –15.42 to –4.98). In addition, the intraclass correlation coefficient and minimal detectable change for MIP were 0.96; 95% CI: 0.93-0.97, and 17.70, respectively. Conclusion Inspiratory muscle training protocol combined with manual therapy and motor control exercise had greater effect in enhancing MIP than did IMT in isolation in moderate smokers in the short term. In addition, both groups experienced changes in MIP but not in lung function.