General Exercise Training Improves Ventilatory and Peripheral Muscle Strength and Endurance in Chronic Airflow Limitation

Abstract

We studied the impact of a 6-wk supervised, multimodality endurance exercise training program (EXT) on strength and endurance of ventilatory and peripheral muscles in patients with chronic airflow limitation (CAL), and determined whether potential improvements contributed to relief of exertional breathlessness (B) and perceived leg effort/discomfort (LE), respectively. Twenty breathless patients with stable CAL (FEV1 = 41 +/- 3% predicted; mean +/- SEM) were tested at 6-wk intervals at baseline, after a nonintervention control period (pre-EXT), and post-EXT. Measurements included: pulmonary function tests (PFTs), maximal inspiratory/expiratory pressures (MIP, MEP), inspiratory muscle endurance (V(LIM)), quadriceps strength and endurance, exercise endurance, and submaximal cycle exercise with cardioventilatory and symptom responses. Measurements at baseline and pre-EXT were identical. Post-EXT, PFTs did not change; exercise endurance measured on the treadmill, cycle ergometer, arm ergometer, and by 6-min walk distance increased 40 +/- 8%, 43 +/- 10%, 12 +/- 5%, and 34 +/- 9%, respectively (p < 0.05); quadriceps strength increased 21 +/- 5% (p < 0.01); MIP and MEP increased 29 +/- 11% and 27 +/- 11%, respectively (p < 0.05); V(LIM) increased almost threefold (p < 0.05). At isotime near end-exercise, B, LE, carbon dioxide production (VCO2), oxygen consumption (VO2), ventilation, and breathing frequency (F) all fell after EXT (p < 0.05): deltaB correlated with deltaF (r = 0.58, p < 0.01). Increased MIP and V(LIM) did not correlate with improved breathlessness or exercise endurance. Similarly, changes in quadriceps strength and endurance did not correlate with changes in LE or exercise endurance. In conclusion, general nonspecific EXT improved ventilatory and peripheral muscle function in severe CAL, but such improvements did not appear to contribute significantly to reduced exertional symptoms and enhanced exercise performance.

Effect of ventilation-feedback training on endurance and perceived breathlessness during constant work-rate leg-cycle exercise in patients with COPD

“…Although the between-group difference in the percentage increase in exercise time appears to be relatively large (104 vs. 68%), the substantial within-group variability precluded statistical significance. These increases in exercise duration are equivalent or greater than that previously reported in the COPD literature, as other investigators have reported improvements ranging from 43 to 77 percent [9][10][11] on CWR leg-cycle ergometer tests. Direct comparisons between studies are difficult, however, because the CWR exercise tests for the present study were performed at 85 percent of the subjects' VO 2peak achieved on the symptom limited progressive leg-cycle exercise test.…”

Recommendations on the use of exercise testing in clinical practice

“…As described earlier, the potential advantage of measuring hL during CPET is that maximal effort is not required; the results of the studies that have used hL are again not unequivocal. In COPD patients, controlled studies did not observe changes in maximal fC or in maximal V9E [258,259,261].…”

“…the improvement in V9O 2 ,peak after rehabilitation in COPD), particularly in patients with the most advanced disease. In some controlled studies, V9O 2 ,peak increased significantly [255][256][257][258], while other studies failed to observe a significant amelioration [259,260]. hL has also been used as an outcome variable, particularly in CHF patients.…”

“…These tests have been shown to be reliable and reproducible [267]. After exercise training, significant reductions in ventilation [255,256,259,261,268] and lactate levels [255,261,268] at identical submaximal work-rates have been observed. These findings suggest an improvement in aerobic metabolism [255,269] and are in agreement with the observation of a significant increase in oxidative enzyme levels (16-40%) in the quadriceps femoris muscle after a strenuous exercise programme [261].…”

Efeitos de um treinamento resistido com tubos elásticos sobre a força muscular, qualidade de vida e dispneia de pacientes com doença pulmonar obstrutiva crônica

“…Studies have shown that there is a reduction in symptoms such as fatigue and dyspnea after pulmonary rehabilitation programs 42,43 . In a study by Gigliotti et al 44 it was verified that training of the upper limbs, in a chronic manner, was able to reduce the symptom of dyspnea associated with increased inspiratory capacity and reduce the sensation of effort in the upper limbs.…”