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Background Lung volume reduction surgery improves quality of life, exercise capacity, and survival in selected patients but is accompanied by significant morbidity. Bronchoscopic approaches may provide similar benefits with less morbidity. Methods In a randomized, sham procedure controlled, double-blind trial, 277 subjects were enrolled at 36 centers. Patients had emphysema, airflow obstruction, hyperinflation, and severe dyspnea. The primary effectiveness measure was a significant improvement in disease-related quality of life (St. George's Respiratory Questionnaire) and changes in lobar lung volumes. The primary safety measure was a comparison of serious adverse events. Results There were 6/121 (5.0%) responders in the treatment group at 6 months, significantly >1/134 (0.7%) in the control group [Bayesian credible intervals (BCI), 0.05%, 9.21%]. Lobar volume changes were significantly different with an average decrease in the treated lobes of -224 mL compared with -17 mL for the control group (BCI, -272, -143). The proportion of responders in St. George's Respiratory Questionnaire was not greater in the treatment group. There were significantly more subjects with a serious adverse event in the treatment group (n=20 or 14.1%) compared with the control group (n=5 or 3.7%) (BCI, 4.0, 17.1), but most were neither procedure nor device related. Conclusions This trial had technical and statistical success but partial-bilateral endobronchial valve occlusion did not obtain clinically meaningful results. Safety results were acceptable and compare favorably to lung volume reduction surgery and other bronchial valve studies. Further studies need to focus on improved patient selection and a different treatment algorithm. Trial registry ClinicalTrials.gov NCT00475007.

Conventional wisdom suggests that exercise training with a personal trainer (PTr) is more beneficial for improving health-related fitness than training alone. However, there are no published data that confirm whether fitness club members who exercise with a PTr in the fitness club setting obtain superior results compared with self-directed training. We hypothesized that club members randomized to receive an evidence-based training program would accrue greater improvements in lean body mass (LBM) and other fitness measures than members randomized to self-training. Men, aged 30-44 years, who were members of a single Southern California fitness club were randomized to exercise with a PTr administering a nonlinear periodized training program (TRAINED, N = 17) or to self-directed training (SELF, N = 17); both groups trained 3 days per week for 12 weeks. Lean body mass was determined by dual-energy x-ray absorptiometry. Secondary outcomes included muscle strength 1 repetition maximum (1RM), leg power (vertical jump), and aerobic capacity (V[Combining Dot Above]O2max). TRAINED individuals increased LBM by 1.3 (0.4) kg, mean (SEM) vs. no change in SELF, p = 0.029. Similarly, significantly greater improvements were seen for TRAINED vs. SELF in chest press strength (42 vs. 19%; p = 0.003), peak leg power (6 vs. 0.6%; p < 0.0001), and V[Combining Dot Above]O2max (7 vs. -0.3%; p = 0.01). Leg press strength improved 38 and 25% in TRAINED and SELF, respectively (p = 0.14). We have demonstrated for the first time in a fitness club setting that members whose training is directed by well-qualified PTrs administering evidence-based training regimens achieve significantly greater improvements in LBM and other dimensions of fitness than members who direct their own training.

PURPOSE At constant work-rates below the gas exchange threshold (VO(2 theta)), VO(2) normally achieves steady-state values within 3 min, whereas at heavier work-rates, VO(2) may continue to rise. The VO(2) response to heavy exercise can be described by a three-exponential model with the slow phase usually commencing 2-3 min after the onset of exercise. The aim of our study was to estimate precisely the VO(2), VCO(2), VE and f(C) required for above-VO(2 theta) exercise from the relationship of the specific variable to work-rate below VO(2 theta) and to compare this with the actual value achieved. METHODS Nine cyclists performed five constant work-rates of 8 min duration, four below VO(2 theta) (40, 80, 120, 160 W) and one midway between VO(2 theta) and VO(2max) (295 +/- 34 W). The VO(2), VCO(2), VE and f(C) were averaged for the final 2 min of each below-VO(2 theta) test and were found to be linear with respect to work-rate (average r2 >0.95). Variables for the above-VO(2 theta) work-rate were predicted by extrapolation and compared with the actual measured values at the end of the exercise bout. RESULTS VO(2) exceeded the predicted value by 0.48 +/- 0.21 L x min(-1) (12.4 +/- 5.1%), VCO(2) by 0.78 +/- 0.26 L x min(-1) (23.2 +/- 7.2%), VE by 40.3 +/- 16.3 L x min(-1) (51.0 +/- 23.1%), and f(C) by 12.2 +/- 12.5 beats x min(-1) (8.8 +/- 9.3%), all P < 0.0001 except f(C) P < 0.02, paired t-test. The point at which VO(2) during above-VO(2 theta) exercise exceeded the predicted value (145.7 +/- 64.9 s) agreed with the point at which the slow component of VO(2) began, as determined by nonlinear regression analysis (131.5 +/- 44.3 s, P = NS, ANOVA). CONCLUSION There is an excessive metabolic response to heavy exercise over and above that predicted by extrapolation from light-moderate exercise and this excess VO(2) approximates on average to the slow phase of a three-compartment exponential model.

Endurance exercise training (EXT) is singly the most important aspect of rehabilitation for patients with chronic pulmonary disease. When effective, this modality of physical reconditioning leads to improved functional exercise capacity and reduced breathlessness. Early implementation is desirable to obtain more meaningful responses (e.g., when FEV1 falls below 50% of the predicted value in patients with chronic obstructive disease). Preparation for effective EXT requires optimization of respiratory system mechanics (e.g., using bronchodilator therapy), prevention of gas exchange failure (i.e., using supplemental oxygen), nutritional guidance, and psychological support (e.g., to overcome stigmata of disability, fear, and inclination to panic). EXT should be applied using a rigorous, scientifically based aerobic exercise prescription (AXRx) that recognizes basic principles of the human response to exercise prescription while considering individual pathophysiological limitations and identifying safety thresholds for exercise participation. The mode of aerobic exercise should use large muscle groups of the legs (e.g., treadmill or cycle ergometer). The recommended duration is an accumulation of 30 min of exercise per session at the target intensity, achieved by continuous or interval training. EXT should be supervised with a recommended frequency of at least three times per week for 6--8 wk. Target exercise intensity can be monitored by oxygen uptake, work rate, heart rate, or perceived exertion. Target intensity can be determined initially on the basis of 40% of a reference value for maximum oxygen uptake and linked to other variables through predictable interrelationships. All aspects of the AXRx must be reviewed with regard to progression during training. Pulmonary rehabilitation must recognize the importance of achieving clinically meaningful responses (e.g., increased 6-min walking distance of 54 m) as well as the need for maintenance exercise program to sustain the benefits.

Chronic pulmonary diseases are common in the community and their pathophysiology is complex. The principal symptoms are dyspnea and limited exercise capacity. Some, but not all, patients have true ventilatory limitation where the maximal exercise ventilation (VEmax) equals the measured maximal ventilatory volume (MVV). Those with obstructive disease have impeded expiration requiring an obligatory expiratory time for adequate lung emptying (i.e., a timing constraint). In these patients, increased breathing frequency during exercise tends to lead to hyperinflation and smaller tidal volumes, circumstances that predictably worsen breathing efficiency (i.e., result in high VD/VT). Those with restrictive disease characteristically have limited inspiratory capacity but-unimpeded or even accelerated expiration (i.e. tidal volume constraint). These patients characteristically exhibit rapid respiratory rates (e.g., >50-min−1) at end exercise.