The Effects of Movement-Based Exercises Combined with Respiratory Techniques on the Thoracic Kyphosis Angle in Individuals with Thoracic Hyperkyphosis: A Systematic Review and Meta-Analysis

Background: Thoracic hyperkyphosis (THK) is a postural deformity associated with pain, impaired respiratory function, reduced quality of life, scapular rhythm impairment, shoulder biomechanical alterations, and increased fall risk. While corrective exercises are commonly used, the added value of integrating specific respiratory techniques remains unclear. This systematic review and meta-analysis aimed to evaluate the effects of movement-based exercises combined with respiratory techniques on the thoracic kyphosis angle (TKA) in individuals with THK. Methods: A systematic search of PubMed, Scopus, Web of Science, CINAHL, SPORTDiscus, PEDro, and CENTRAL Cochrane Library was conducted from inception to 16 July 2026. Randomized controlled trials (RCTs) and non-randomized controlled trials (non-RCTs) investigating combined exercise and respiratory interventions in individuals with THK were included. The primary outcome was TKA. Two authors independently selected studies, extracted data, and assessed quality, with a third author resolving discrepancies. Risk of bias was assessed using RoB-2 for RCTs and ROBINS-I for non-RCTs. Certainty of evidence was graded using GRADE. A random-effects meta-analysis of TKA was performed using Hedges’ g. Results: Five studies involving 247 participants were included. Meta-analysis demonstrated a significant reduction in TKA following combined intervention compared with exercise alone (Hedges’ g = 0.667, 95% CI: 0.395 to 0.940, p < 0.001; I2 = 39.7%). Subgroup analysis by age group revealed significant improvement in adolescents (Hedges’ g = 0.860, 95% CI: 0.532 to 1.189, p < 0.001; I2 = 0%) but no significant effect in older adults (Hedges’ g = 0.241, 95% CI: −0.247 to 0.729, p = 0.333; I2 = 0%). The certainty of evidence for TKA was graded as moderate, with downgrading for risk of bias, indirectness, and potential publication bias. Conclusions: Movement-based exercises combined with respiratory techniques significantly improve thoracic alignment in individuals with THK, with moderate certainty evidence, particularly in adolescents. The evidence in older adults remains inconclusive due to limited studies and structural factors. Larger, high-quality, and standardized trials are needed to confirm these effects, establish optimal treatment parameters, and evaluate long-term outcomes across diverse populations.