This study will determine the dyspnea response in chronic lung disease volunteers during treadmill walking with and without added inspiratory resistance. This study will also determine the level of dyspnea and exercise sense of effort in individuals walking on a treadmill when elevations occur. Comparisons will be made of a participant's exercise response with and without increased inspiratory resistance. In this study, exercise performance will be analyzed based on physiological and perceptual measures. The participant will undergo two sessions: one session will be a standard exercise walking test without an inspiratory resistance; the other session will be the same standard exercise walking test while breathing with an inspiratory resistance equal to a N95 facemask (R=10-15 cmH2O/L/sec). Performance will be determined by physiological measures. Perception will be determined by scores based on numerical scales and automatically with the forehead Vitality remote monitoring sensor.

Inclusion Criteria:

• Former pulmonary rehabilitation patients that are now participating in maintenance exercise classes
• Males and females with an age range of 18 years or older
• Subjects must be able to walk on treadmill for multiple sessions

Exclusion Criteria:

• The subjects in each experiment will be recruited for a distribution of gender, ethnicity and age

Patients undergoing respiratory therapy at John Muir Health which encompasses a variety of pulmonary conditions