Background: Respiratory muscular weakness and associated changes in thoracoabdominal motion have been poorly studied in stroke subjects, since the individuals' functional levels were not previously considered in the investigations.
Aim: To investigate the breathing patterns, thoracoabdominal motion, and respiratory muscular strength in chronic stroke subjects, who were stratified into two groups, according to their walking speeds.
Design: Cross-sectional, observational study.
Setting: University laboratory.
Population: Eighty-nine community-dwelling chronic stroke subjects
Methods: The subjects, according to their gait speeds, were stratified into community (gait speed ≥0.8 m/s) and non-community ambulators (gait speed <0.8 m/s). Variables related to pulmonary function, breathing patterns, and thoracoabdominal motions were assessed. Measures of maximal inspiratory pressure (MIP) and maximal expiratory pressure (MEP) were obtained and were compared with the reference values for the Brazilian population. The MIP and MEP values were expressed as percentages of the predicted values. Mann-Whitney-U or independent Student t-tests were employed to compare the differences between the two groups for the selected variables.
Results: No significant between-group differences were found for the variables related to the breathing patterns and thoracoabdominal motions (0.01 < z/t < 1.51; 0.14<P<0.99). Compared to the predicted values, the stroke subjects demonstrated decreases of 26.5 and 20% of the MIP and MEP, respectively. Non-community ambulators showed significant lower predicted MIP values than those from the community ambulators (t=2.10; P=0.04). However, no significant between-group differences were found for the predicted MEP measures (t = -1.10; P=0.25).
Conclusion: Stroke subjects demonstrated weakness of the respiratory muscles and lower predicted MIP values were found for the non-community ambulators.
Clinical rehabilitation impact: Evaluations and interventions involving respiratory muscular training could be included in stroke rehabilitation, especially for individuals with lower functional levels.