**10. Adjuncts to exercise training**

### **10.1 Neuromuscular electrical training**

Several COPD patients with advanced lung disease who are bed bound or wheelchair bound are unable to participate in a conventional pulmonary rehabilitation program. To help these patients, a new modality of transcutaneous neuromuscular electrical stimulation (NMES) has been devised recently [129–131]. This technology involves application of low amplitude electric current via electrodes transcutaneously to the targeted muscle groups by depolarizing motor neurons. Low intensity electric current (10–100 mA) is delivered at stimulation frequencies between 8 and 120 Hz for duration of 250–400 ms. Although no large RCTs are available, a recent meta-analysis did report improvement in quadriceps strength and exercise capacity with NMES. Unfortunately, no significant improvement in HRQoL in moderate to

**13**

*Pulmonary Rehabilitation in Chronic Obstructive Pulmonary Disease*

severe COPD was seen [132]. Apart from debilitated COPD patients, this technology has been recommended for use during COPD exacerbation, as it has low impact

A pulmonary rehabilitation programs for COPD patients usually includes respiratory muscle training. The goal of this training is to improve the abnormal breathing pattern, which may result due to increased work of breathing, chest wall changes and poor breathing habits in COPD patients [135–138]. The most commonly applied approach is through the endurance and strength training. [26]. Exercise training can lead to increase in minute ventilation, which leads to an increase in work of breathing. Constant controlled aerobic exercises of upper and lower extremities can lead to a recurrent stimulation to respiratory muscles. This helps the COPD patients to modify their breathing patterns on a day-to-day basis as

Apart from exercise training, specific breathing exercises such as diaphragmatic breathing, paced breathing with exercises and pursed lip breathing has been proven to be beneficial in COPD patients. Diaphragm, which is the main inspiratory muscle, is flattened and ineffective in patients with hyperinflated lungs. This puts these patients at a mechanical disadvantage to adequately maintain and increase their minute ventilation. COPD patients who undergo the training to improve the coordination of their diaphragmatic muscle tend to fare better overall [139].

Many patients with emphysema self-discover the method of purse lip breathing for faster recovery from shortness of breath post exercise. Other patients can be instructed regarding this method. It helps patients to increase alveolar ventilation, tidal volume and CO2 removal. It also leads to slow expiratory flow and decreased respiratory rate [140]. Using the same principle, respiratory muscles can be trained by using resistive breathing devices. This can be particularly useful in patients who

Additionally COPD patients specifically with chronic bronchitis occasionally have ineffectual cough leading to difficulty in respiratory secretion clearance. Instructions on special coughing techniques (huffing, autogenic drainage) combined with oscillating expiratory breathing devices (Acapella, In-exsufflator) can prove effective [141]. Patients can be instructed to perform daily chest physiotherapy to assist in respiratory secretion clearance through postural drainage techniques [142]. A meta-analysis of 32 studies focusing on respiratory muscle training showed that it leads to improvement in respiratory muscle strength, exercise capacity and

The beneficial effects of a comprehensive pulmonary rehabilitation program are not sustained beyond 12 months [32, 42, 144, 145]. On the other hand, repeating a pulmonary rehabilitation programs has not been found to be an effective treatment option [146]. Considering this, it is challenging to maintain the changes made in physical activity and lifestyle due to a pulmonary rehabilitation. Although there is a lack of data on maintenance programs, some centers do provide these in the hope to achieve prolonged benefits gathered in a successful rehabilitation program. There are no set guidelines to establish an optimal strategy for providing maintenance pulmonary rehabilitation. Additionally other factors such as lack of transportation

continue to have dyspnea despite optimal medical management.

*DOI: http://dx.doi.org/10.5772/intechopen.81742*

**10.2 Respiratory muscle training**

on ventilation, heart rate and dyspnea [133, 134].

well as be better prepared for an exacerbation.

perception of exertional dyspnea [143].

**11. Maintenance of the training**

severe COPD was seen [132]. Apart from debilitated COPD patients, this technology has been recommended for use during COPD exacerbation, as it has low impact on ventilation, heart rate and dyspnea [133, 134].
