Neuromuscular, acute symptoms and cardiorespiratory responses to progressive elastic resistance training in patients with chronic obstructive pulmonary disease: cross- sectional study

Purpose: To evaluate neuromuscular, acute symptoms and cardiorespiratory responses during progressive elastic resistance training in patients with chronic obstructive pulmonary disease (COPD).Methods: 14 patients diagnosed with moderate-very severe COPD performed knee extensions at different elastic resistance levels. Normalized Root Mean Square (nRMS) was measured for the rectus femoris (RF), vastus lateralis (VL) and vastus medialis (VM), together with rate of perceived exertion (RPE), perceived quadriceps fatigue, dyspnea, oxygen saturation and heart rate. Results: For the VL, a nRMS increase was evident from a two-level increment when using the red color. When using the green and blue colors, four and three level increments were needed to increase nRMS, respectively. For the VM, there were no nRMS progressions. For the RF, a nRMS increase was evident from a two-level increment when using the red color and after one-level when using the green color. Dyspnea, quadriceps fatigue and especially RPE increased in a dose-response fashion and were correlated (p<0.01) with the relative resistance (i.e., % of the maximum resistance), resistance level (i.e., color) and nRMS at the three muscles.Conclusions: Heavy elastic resistance training is feasible in COPD patients, without excessive dyspnea and with stable cardiorespiratory response.