Outcome
Type |
Measure |
Description |
Time frame |
Safety issue |
Primary |
Dyspnea Intensity |
Dyspnea (respiratory discomfort) will be defined as the perceived "sensation of breathing discomfort" experienced at rest or during pedaling. Measurements will be made at rest (the steady-state period after at least 3 minutes of breathing on the mouthpiece before exercise starts), at two-minute intervals during exercise, and at end-exercise (at 2 minutes or the last 30-sec of loaded pedaling achieved by the participants). The intensity (strength) of sensations will be rated using the 10-point Borg scale (Modified Borg Dyspnoea Scale; scale from 0 to 10 in 1 unit increments, where 0 represents "Nothing at all" intensity and 10 represents "Maximal" intensity). |
At isotime (maximum exercise time achieved by all participants during a standard CPET) from baseline (rest) up to 20 minutes. |
|
Primary |
Leg discomfort Intensity |
Leg discomfort will be defined as the perceived "sensation of leg discomfort" experienced at rest or during pedaling. Measurements will be made at rest (the steady-state period after at least 3 minutes of breathing on the mouthpiece before exercise starts), at two-minute intervals during exercise, and at end-exercise (at 2 minutes or the last 30-sec of loaded pedaling achieved by the participants). The intensity (strength) of sensations will be rated using the 10-point Borg scale (Modified Borg Dyspnoea Scale; scale from 0 to 10 in 1 unit increments, where 0 represents "Nothing at all" intensity and 10 represents "Maximal" intensity). |
At isotime (maximum exercise time achieved by all participants during a standard CPET) from baseline (rest) up to 20 minutes.. |
|
Primary |
Inspiratory Neural Drive (IND) as measured by Diaphragmatic electromyography (EMGdi) |
An esophageal electrode-balloon catheter consisting of 5 electrode pairs and two balloons, will be inserted nasally and positioned for optimal recording. Electromyogram output of the diaphragm (used as an index of inspiratory neural drive to crural diaphragm or diaphragm activation; EMGdi) will be recorded continuously at rest and during exercise. Maximal EMGdi (EMGdi,max) will be determined from IC maneuvers. EMGdi/EMGdi,max will be used as an index of the inspiratory neural drive to the crural diaphragm. |
At isotime (maximum exercise time achieved by all participants during a standard CPET) from baseline (rest) up to 20 minutes.. |
|
Secondary |
Ventilation |
Ventilation will be measured on a breath-by-breath basis using a SensorMedics Vmax229 metabolic measurement system. Measurements will be compared with predicted values based on age and height. Three main time points will be evaluated: "rest" defined as the steady-state period after at least 3 minutes of quiet breathing on the mouthpiece before exercise starts; "isotime" defined as the last 30-sec increment of each minute (i.e., 1-min, 2-min, 3-min) during the incremental exercise test and at 2 minutes (or the longest time achieved by all subjects) during the constant load exercise tests, and; "end-exercise" defined as the last 30-sec of loaded pedaling. |
At isotime (maximum exercise time achieved by all participants during a standard CPET) from baseline (rest) up to 20 minutes.. |
|
Secondary |
Respiratory Frequency |
Respiratory frequency will be measured on a breath-by-breath basis using a SensorMedics Vmax229 metabolic measurement system. Measurements will be compared with predicted values based on age and height. Three main time points will be evaluated: "rest" defined as the steady-state period after at least 3 minutes of quiet breathing on the mouthpiece before exercise starts; "isotime" defined as the last 30-sec increment of each minute (i.e., 1-min, 2-min, 3-min) during the incremental exercise test and at 2 minutes (or the longest time achieved by all subjects) during the constant load exercise tests, and; "end-exercise" defined as the last 30-sec of loaded pedaling. |
At isotime (maximum exercise time achieved by all participants during a standard CPET) from baseline (rest) up to 20 minutes.. |
|
Secondary |
Inspiratory Capacity |
Inspiratory capacity will be measured using a SensorMedics Vmax 229 metabolic measurement system. Measurements will be made at rest (the steady-state period after at least 3 minutes of breathing on the mouthpiece before exercise starts), at two-minute intervals during exercise, and at end-exercise (at 2 minutes or the last 30-sec of loaded pedaling achieved by the participants). |
At isotime (maximum exercise time achieved by all participants during a standard CPET) from baseline (rest) up to 20 minutes.. |
|
Secondary |
Carbon Dioxide Output (VECO2) |
Carbon dioxide output (VECO2) will be measured on a breath-by-breath basis using a SensorMedics Vmax229 metabolic measurement system. Three main time points will be evaluated: "rest" defined as the steady-state period after at least 3 minutes of quiet breathing on the mouthpiece before exercise starts; "isotime" defined as the last 30-sec increment of each minute (i.e., 1-min, 2-min, 3-min) during the incremental exercise test and at 2 minutes (or the longest time achieved by all subjects) during the constant load exercise tests, and; "end-exercise" defined as the last 30-sec of loaded pedaling. |
At isotime (maximum exercise time achieved by all participants during a standard CPET) from baseline (rest) up to 20 minutes.. |
|
Secondary |
Oxygen Uptake (VEO2) |
Oxygen uptake (VEO2) will be measured on a breath-by-breath basis using a SensorMedics Vmax229 metabolic measurement system. Three main time points will be evaluated: "rest" defined as the steady-state period after at least 3 minutes of quiet breathing on the mouthpiece before exercise starts; "isotime" defined as the last 30-sec increment of each minute (i.e., 1-min, 2-min, 3-min) during the incremental exercise test and at 2 minutes (or the longest time achieved by all subjects) during the constant load exercise tests, and; "end-exercise" defined as the last 30-sec of loaded pedaling. |
At isotime (maximum exercise time achieved by all participants during a standard CPET) from baseline (rest) up to 20 minutes.. |
|
Secondary |
Transdiaphragmatic pressure (Pdi) |
An esophageal electrode-balloon catheter consisting of 5 electrode pairs and two balloons, will be inserted nasally and positioned for optimal recording. Esophageal (Pes) and gastric pressures (Pga) will be recorded continuously at rest and during exercise. Transdiaphragmatic pressure (Pdi) will be recorded as the difference between Pga and Pes signals. |
At isotime (maximum exercise time achieved by all participants during a standard CPET) from baseline (rest) up to 20 minutes.. |
|
Secondary |
Partial pressure of arterialized (capillary) carbon dioxide (PaCO2) |
Earlobe arterialized blood will be collected at rest, and at end-exercise. Earlobe arterialized capillary blood gas sampling will be used to measure partial pressure of arterialized (capillary) carbon dioxide (PaCO2). PaCO2 values will be used to calculate ventilatory dead space. |
At isotime (maximum exercise time achieved by all participants during a standard CPET) from baseline (rest) up to 20 minutes.. |
|
Secondary |
Exercise Endurance Time |
The time difference (in minutes and seconds) between the start of loaded pedaling until end-exercise (symptom limitation) of the cardiopulmonary exercise test performed on a stationary bicycle at 75% of maximum work rate. |
Time difference from start to isotime (maximum exercise time achieved by all participants) during a standard cardiopulmonary exercise test (cycle ergometer) up to 20 minutes. |
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