Inspiratory muscle training in quadriplegic patients.

OBJECTIVE To determine whether inspiratory muscle training can increase strength and endurance of these muscles in quadriplegic patients. METHODS Eight quadriplegic patients (7 males and 1 female) with injury to the lower cervical spine (segments C4-C7) were submitted to inspiratory muscle training with a threshold inspiratory muscle trainer adjusted to 30% of MIP. The training sessions were carried out with the patients in a sitting position, 5 days a week for 8 weeks. Endurance time, MIP, MEP and FVC were determined at baseline, week 4 and week 8. RESULTS In comparison with the mean baseline value, there was an increase in MIP, measured in the sitting position, at weeks 4 and 8 (-83.0 +/- 18.9 cmH2O vs. -104.0 +/- 19.4 cmH2O and -111.3 +/- 22.7 cmH2O). There was an increase in MEP, also in the sitting position, at week 4 (from 36.8 +/- 8.1 to 42.6 +/- 8.8 cmH2O). There was an improvement in FVC at week 4 (from 2.1 +/- 0.8 to 2.5 +/- 0.6 L, representing an increase of 24 +/- 22%). Although there was an increase in endurance (sitting) at week 8, the difference was not significant in comparison with the baseline value (29.8 +/- 21.0 vs. 35.9 +/- 15.5 min, an increase of 173 +/- 233%). CONCLUSIONS Quadriplegic patients can benefit from training at low loads (30% of MIP), which can improve inspiratory muscle strength, FVC and expiratory muscle performance.