Home-Based Respiratory Muscle Training and Aerobic Exercise Programs to Improve Lung Health in Current and Former Cigarette Smokers

The primary objective is in the feasibility of conducting the respiratory muscle training (RMT) and aerobic exercise (AE) intervention relative to the sham control. In the RMT group, overall compliance (e.g., compliant at all time points) will be estimated using 90% confidence intervals (CIs) obtained Clopper-Pearson method. The lower bounds will define a plausible lower limit for true (unobserved) compliance rates. Additionally, compliance status will be modeled as a function of time (e.g., week), and pre-specified exogenous factors using a generalized estimating equation logistic regression model (autoregressive covariance structure). Estimates of compliance rates will be obtained by time-point and tests about the appropriate contrasts of model estimates will be used to determine if there is a time trend.

The primary objective is in the feasibility of conducting the RMT and AE intervention relative to the sham control. In the RMT group, overall adherence (complete ≥ 70% of sessions) rates will be estimated using 90% CIs obtained Clopper-Pearson method. The lower bounds will define a plausible lower limit for true (unobserved) adherence rates.

Participants will complete 3 sets of 15 breaths, 5 days/week using commercially available Power Lung. resistance will be increased 5-10% every week . Participants will rate and log their effort

The SGRQ comprises of 50 items and consists of two parts. Scores range from 0-100, with higher scores indicating worse quality of life.

Measured by the 6-Minute Walk Test. Will be summarized at pre-, 6-week and post-intervention timepoints, regardless of treatment regimen, using the appropriate descriptive statistics and graphically summarized. The outcome will be analyzed using a linear mixed model, with the intervention arms and time points as predictors. Baseline measurements will be included as a covariate to adjust for initial differences. Both within-and between-group comparisons will be conducted using appropriate contrasts. The primary comparisons will focus on between-arm differences at the 12-week post-intervention time point. Comparisons at the 6-week and 3-month follow-up visits will be secondary and will only be performed if the primary comparison for the corresponding endpoint reaches statistical significance. For cohort A, Bonferroni's correction will be applied to adjust for three pairwise comparisons.

Measured using the 30-Second Sit-to-Stand Test. The outcome will be analyzed using a linear mixed model, with the intervention arms and time points as predictors. Baseline measurements will be included as a covariate to adjust for initial differences. Both within-and between-group comparisons will be conducted using appropriate contrasts. The primary comparisons will focus on between-arm differences at the 12-week post-intervention time point.

Measured using the Short Physical Performance Battery. The outcome will be analyzed using a linear mixed model, with the intervention arms and time points as predictors. Baseline measurements will be included as a covariate to adjust for initial differences. Both within-and between-group comparisons will be conducted using appropriate contrasts. The primary comparisons will focus on between-arm differences at the 12-week post-intervention time point.

daily step counts and minutes at various intensity levels will be monitored with an activity tracker. Both within-and between-group comparisons will be conducted using appropriate contrasts. The primary comparisons will focus on between-arm differences at the 12-week post-intervention time point.

he Functional Assessment of Chronic Illness Therapy (FACIT- fatigue scale) is a 13-item patient-reported measure of fatigue. Items are scored on a 0 - 4 response scale with anchors ranging from "Not at all" to "Very much so". To score the FACIT-fatigue, all items are summed to create a single fatigue score with a range from 0 to 52. The higher the score, the lower the score the greater the fatigue severity

The outcome will be analyzed using a linear mixed model, with the intervention arms and time points as predictors. Baseline measurements will be included as a covariate to adjust for initial differences. Both within-and between-group comparisons will be conducted using appropriate contrasts. The primary comparisons will focus on between-arm differences at the 12-week post-intervention time point.

Will assess cardiac biomarkers, such as high-sensitivity troponin T and N-terminal pro-brain natriuretic peptide. The outcome will be analyzed using a linear mixed model, with the intervention arms and time points as predictors. Baseline measurements will be included as a covariate to adjust for initial differences. Both within-and between-group comparisons will be conducted using appropriate contrasts. The primary comparisons will focus on between-arm differences at the 12-week post-intervention time point. Biomarker data will be appropriately transformed prior to analysis to meet model assumptions.

he Dyspnea-12 describes the different qualitative dimensions of breathlessness. Each 12- item (seven for the physical and five for the affective components) score ranges from 'none' (score 0) to 'severe' (score 3) with a total score ranging from 0 to 36 (lower is better), a physical score ranging from 0 to 21 and an affective score ranging from 0 to 15