People with chronic heart failure (CHF) often suffer from exercise intolerance due to dyspnea and fatigue, and both respiratory and peripheral muscle weakness contribute to these manifestations. Unfortunately, these symptoms can often cause a decline in overall quality of life (QOL) for patients. Respiratory muscle training (RMT) as well as aerobic exercise (AE) have been shown to improve exercise capacity, dyspnea and QOL in this patient group. The potential additive effects of the two methods, however, are unclear.

In order to determine the efficacy of RMT and AE on heart failure, research into both methods was conducted. This study (Winkelmann, et al) aims to test additional effects of inspiratory muscle training (IMT) when added to AE in patients with CHF and inspiratory muscle weakness.

Key Findings

• Respiratory muscle weakness contributes to fatigue and dyspnea in people with heart failure (HF).
• Incremental respiratory muscle training (RMT) aims to increase endurance by increasing training intensity.
• 10 weeks of incremental RMT improved respiratory muscle strength, exercise capacity, peak oxygen uptake, dyspnea, quality of life and reduced the heart rate in people with HF.

Patient Impact

Incremental RMT effectively improves respiratory function, exercise capacity, oxygen uptake and heart rate in people with HF.

Study Methods

Patients with CHF underwent 12 weeks of AE plus IMT. Respiratory and cardiopulmonary function, exercise capacity (6MWT) and QOL were assessed before and after the training period. They were also compared to a control group who did AE only.

Study Results

The results of the aforementioned study were striking. PImax, VO2 peak, circulatory power, oxygen uptake efficiency slope, ventilatory efficiency, ventilatory oscillation, and oxygen uptake efficiency slope all improved significantly in the AE plus IMT group when compared to the AE only group. The QOL of patients increased accordingly.

In conclusion, using RMT in addition to general aerobic exercise results in improved respiratory function and cardiorespiratory responses. This is important as it shows that RMT makes AE more efficient. This can be clinically meaningful as better cardiopulmonary function is associated with better diagnosis in patients with CHF.

References

Winkelmann ER, et al Addition of inspiratory muscle training to aerobic training improves cardiorespiratory responses to exercise in patients with heart failure and inspiratory muscle weakness. Am. Heart J. 158(5), 768.e1–768.e7 (2009).