an individual who meets any of the following criteria will be excluded from participation in this study: * above normal performance (i.e, \>=100% predicted) in the 6mwt based on normative data for gender and age * history or cardiac condition as determined by nih cardiology to be unsafe for exercise participation (e.g. ischemic heart disease, right- or left-sided heart failure, cor pulmonale or pulmonary hypertension, dilated or hypertrophic cardiomyopathy or non-idiopathic cardiomyopathy) * significant hepatic or renal dysfunction * cancer diagnosis with evidence of metastasis or a life expectancy of less than one year * history of stroke resulting in impairments in functional mobility that limits safe participation * active substance abuse including etoh * severe psychiatric disease, not responsive to treatment or medication * history of diabetes and on insulin pump therapy, or uncontrolled diabetes with hba1c \> 9.0% * pregnancy * acceptance onto a lung transplant waiting list * extreme obesity with bmi \> 40 kg/m2 * on medications that would influence exercise performance such as beta blockers or antiretroviral therapy * ongoing tobacco and/or nicotine product use * enrolled in another interventional clinical research trial * any other medical or health condition(s) that unduly increases the risk of exercise testing or training, affects the normal physiologic response to exercise testing or training, and/or would otherwise interfere with the ability to interpret the data as determined by the pi

an individual who meets any of the following criteria will be excluded from participation in this study: * above normal performance (i.e, \>=100% predicted) in the 6mwt based on normative data for gender and age * history or cardiac condition as determined by nih cardiology to be unsafe for exercise participation (e.g. ischemic heart disease, right- or left-sided heart failure, cor pulmonale or pulmonary hypertension, dilated or hypertrophic cardiomyopathy or non-idiopathic cardiomyopathy) * significant hepatic or renal dysfunction * cancer diagnosis with evidence of metastasis or a life expectancy of less than one year * history of stroke resulting in impairments in functional mobility that limits safe participation * active substance abuse including etoh * severe psychiatric disease, not responsive to treatment or medication * history of diabetes and on insulin pump therapy, or uncontrolled diabetes with hba1c \> 9.0% * pregnancy * acceptance onto a lung transplant waiting list * extreme obesity with bmi \> 40 kg/m2 * on medications that would influence exercise performance such as beta blockers or antiretroviral therapy * ongoing tobacco and/or nicotine product use * enrolled in another interventional clinical research trial * any other medical or health condition(s) that unduly increases the risk of exercise testing or training, affects the normal physiologic response to exercise testing or training, and/or would otherwise interfere with the ability to interpret the data as determined by the pi

an individual who meets any of the following criteria will be excluded from participation in this study: above normal performance (i.e, >=100% predicted) in the 6mwt based on normative data for gender and age history or cardiac condition as determined by nih cardiology to be unsafe for exercise participation (e.g. ischemic heart disease, right- or left-sided heart failure, cor pulmonale or pulmonary hypertension, dilated or hypertrophic cardiomyopathy or non-idiopathic cardiomyopathy) significant hepatic or renal dysfunction cancer diagnosis with evidence of metastasis or a life expectancy of less than one year history of stroke resulting in impairments in functional mobility that limits safe participation active substance abuse including etoh severe psychiatric disease, not responsive to treatment or medication history of diabetes and on insulin pump therapy, or uncontrolled diabetes with hba1c > 9.0% pregnancy acceptance onto a lung transplant waiting list extreme obesity with bmi > 40 kg/m2 on medications that would influence exercise performance such as beta blockers or antiretroviral therapy ongoing tobacco and/or nicotine product use enrolled in another interventional clinical research trial any other medical or health condition(s) that unduly increases the risk of exercise testing or training, affects the normal physiologic response to exercise testing or training, and/or would otherwise interfere with the ability to interpret the data as determined by the pi

an individual who meets any of the following criteria will be excluded from participation in this study: above normal performance (i.e, >=100% predicted) in the 6mwt based on normative data for gender and age history or cardiac condition as determined by nih cardiology to be unsafe for exercise participation (e.g. ischemic heart disease, right- or left-sided heart failure, cor pulmonale or pulmonary hypertension, dilated or hypertrophic cardiomyopathy or non-idiopathic cardiomyopathy) significant hepatic or renal dysfunction cancer diagnosis with evidence of metastasis or a life expectancy of less than one year history of stroke resulting in impairments in functional mobility that limits safe participation active substance abuse including etoh severe psychiatric disease, not responsive to treatment or medication history of diabetes and on insulin pump therapy, or uncontrolled diabetes with hba1c > 9.0% pregnancy acceptance onto a lung transplant waiting list extreme obesity with bmi > 40 kg/m2 on medications that would influence exercise performance such as beta blockers or antiretroviral therapy ongoing tobacco and/or nicotine product use enrolled in another interventional clinical research trial any other medical or health condition(s) that unduly increases the risk of exercise testing or training, affects the normal physiologic response to exercise testing or training, and/or would otherwise interfere with the ability to interpret the data as determined by the pi

an individual who meets any of the following criteria will be excluded from participation in this study: above normal performance (i.e, greater than or equal to 100% predicted) in the 6mwt based on normative data for gender and age (86,87) history or cardiac condition as determined by nih cardiology to be unsafe for exercise participation (e.g. ischemic heart disease, right- or left-sided heart failure, cor pulmonale or pulmonary hypertension, dilated or hypertrophic cardiomyopathy or non-idiopathic cardiomyopathy) significant hepatic or renal dysfunction cancer diagnosis with evidence of metastasis or a life expectancy of less than one year history of stroke resulting in impairments in functional mobility that limits safe participation active substance abuse including etoh severe psychiatric disease, not responsive to treatment or medication history of diabetes and on insulin pump therapy, or uncontrolled diabetes with hba1c > 9.0% pregnancy acceptance onto a lung transplant waiting list extreme obesity with bmi > 40 kg/m^2 on medications that would influence exercise performance such as beta blockers or antiretroviral therapy ongoing tobacco and/or nicotine product use enrolled in another interventional clinical research trial any other medical or health condition(s) that unduly increases the risk of exercise testing or training, affects the normal physiologic response to exercise testing or training, and/or would otherwise interfere with the ability to interpret the data as determined by the pi

an individual who meets any of the following criteria will be excluded from participation in this study: above normal performance (i.e, greater than or equal to 100% predicted) in the 6mwt based on normative data for gender and age (86,87) history or cardiac condition as determined by nih cardiology to be unsafe for exercise participation (e.g. ischemic heart disease, right- or left-sided heart failure, cor pulmonale or pulmonary hypertension, dilated or hypertrophic cardiomyopathy or non-idiopathic cardiomyopathy) significant hepatic or renal dysfunction cancer diagnosis with evidence of metastasis or a life expectancy of less than one year history of stroke resulting in impairments in functional mobility that limits safe participation active substance abuse including etoh severe psychiatric disease, not responsive to treatment or medication history of diabetes and on insulin pump therapy, or uncontrolled diabetes with hba1c > 9.0% pregnancy acceptance onto a lung transplant waiting list extreme obesity with bmi > 40 kg/m^2 on medications that would influence exercise performance such as beta blockers or antiretroviral therapy ongoing tobacco and/or nicotine product use enrolled in another interventional clinical research trial any other medical or health condition(s) that unduly increases the risk of exercise testing or training, affects the normal physiologic response to exercise testing or training, and/or would otherwise interfere with the ability to interpret the data as determined by the pi

an individual who meets any of the following criteria will be excluded from participation in this study: above normal performance (i.e, greater than or equal to 100% predicted) in the 6mwt based on normative data for gender and age (85,86) history or cardiac condition as determined by nih cardiology to be unsafe for exercise participation (e.g. ischemic heart disease, right- or left-sided heart failure, cor pulmonale or pulmonary hypertension, dilated or hypertrophic cardiomyopathy or non-idiopathic cardiomyopathy) significant hepatic or renal dysfunction cancer diagnosis with evidence of metastasis or a life expectancy of less than one year history of stroke resulting in impairments in functional mobility that limits safe participation active substance abuse including etoh severe psychiatric disease, not responsive to treatment or medication history of diabetes and on insulin pump therapy, or uncontrolled diabetes with hba1c > 9.0% pregnancy acceptance onto a lung transplant waiting list extreme obesity with bmi > 40 kg/m2 on medications that would influence exercise performance such as beta blockers or antiretroviral therapy ongoing tobacco and/or nicotine product use enrolled in another interventional clinical research trial any other medical or health condition(s) that unduly increases the risk of exercise testing or training, affects the normal physiologic response to exercise testing or training, and/or would otherwise interfere with the ability to interpret the data as determined by the pi inclusion of vulnerable participants: participation of employees: nih employees may be enrolled in this study as this population meets the study entry criteria. neither participation nor refusal to participate as a participant in the research will have an effect, either beneficial or adverse, on the participant s employment or position at nih. every effort will be made to protect participant information, but such information may be available in medical records and may be available to authorized users outside of the study team in both an identifiable and unidentifiable manner. the nih information sheet on employee research participation will be made available.

an individual who meets any of the following criteria will be excluded from participation in this study: above normal performance (i.e, greater than or equal to 100% predicted) in the 6mwt based on normative data for gender and age (85,86) history or cardiac condition as determined by nih cardiology to be unsafe for exercise participation (e.g. ischemic heart disease, right- or left-sided heart failure, cor pulmonale or pulmonary hypertension, dilated or hypertrophic cardiomyopathy or non-idiopathic cardiomyopathy) significant hepatic or renal dysfunction cancer diagnosis with evidence of metastasis or a life expectancy of less than one year history of stroke resulting in impairments in functional mobility that limits safe participation active substance abuse including etoh severe psychiatric disease, not responsive to treatment or medication history of diabetes and on insulin pump therapy, or uncontrolled diabetes with hba1c > 9.0% pregnancy acceptance onto a lung transplant waiting list extreme obesity with bmi > 40 kg/m2 on medications that would influence exercise performance such as beta blockers or antiretroviral therapy ongoing tobacco and/or nicotine product use enrolled in another interventional clinical research trial any other medical or health condition(s) that unduly increases the risk of exercise testing or training, affects the normal physiologic response to exercise testing or training, and/or would otherwise interfere with the ability to interpret the data as determined by the pi inclusion of vulnerable participants: participation of employees: nih employees may be enrolled in this study as this population meets the study entry criteria. neither participation nor refusal to participate as a participant in the research will have an effect, either beneficial or adverse, on the participant s employment or position at nih. every effort will be made to protect participant information, but such information may be available in medical records and may be available to authorized users outside of the study team in both an identifiable and unidentifiable manner. the nih information sheet on employee research participation will be made available.

an individual who meets any of the following criteria will be excluded from participation in this study: 1. above normal performance (i.e, greater than or equal to 100% predicted) in the 6mwt based on normative data for gender and age (85,86) 2. history or cardiac condition as determined by nih cardiology to be unsafe for exercise participation (e.g. ischemic heart disease, right- or left-sided heart failure, cor pulmonale or pulmonary hypertension, dilated or hypertrophic cardiomyopathy or non-idiopathic cardiomyopathy) 3. significant hepatic or renal dysfunction 4. cancer diagnosis with evidence of metastasis or a life expectancy of less than one year 5. history of stroke resulting in impairments in functional mobility that limits safe participation 6. active substance abuse including etoh 7. severe psychiatric disease, not responsive to treatment or medication 8. history of diabetes and on insulin pump therapy, or uncontrolled diabetes with hba1c > 9.0% 9. pregnancy 10. acceptance onto a lung transplant waiting list 11. extreme obesity with bmi > 40 kg/m2 12. on medications that would influence exercise performance such as beta blockers or antiretroviral therapy 13. ongoing tobacco and/or nicotine product use 14. enrolled in another interventional clinical research trial 15. any other medical or health condition(s) that unduly increases the risk of exercise testing or training, affects the normal physiologic response to exercise testing or training, and/or would otherwise interfere with the ability to interpret the data as determined by the pi inclusion of vulnerable participants: participation of employees: nih employees may be enrolled in this study as this population meets the study entry criteria. neither participation nor refusal to participate as a participant in the research will have an effect, either beneficial or adverse, on the participant s employment or position at nih. every effort will be made to protect participant information, but such information may be available in medical records and may be available to authorized users outside of the study team in both an identifiable and unidentifiable manner. the nih information sheet on employee research participation will be made available.

an individual who meets any of the following criteria will be excluded from participation in this study: 1. above normal performance (i.e, greater than or equal to 100% predicted) in the 6mwt based on normative data for gender and age (85,86) 2. history or cardiac condition as determined by nih cardiology to be unsafe for exercise participation (e.g. ischemic heart disease, right- or left-sided heart failure, cor pulmonale or pulmonary hypertension, dilated or hypertrophic cardiomyopathy or non-idiopathic cardiomyopathy) 3. significant hepatic or renal dysfunction 4. cancer diagnosis with evidence of metastasis or a life expectancy of less than one year 5. history of stroke resulting in impairments in functional mobility that limits safe participation 6. active substance abuse including etoh 7. severe psychiatric disease, not responsive to treatment or medication 8. history of diabetes and on insulin pump therapy, or uncontrolled diabetes with hba1c > 9.0% 9. pregnancy 10. acceptance onto a lung transplant waiting list 11. extreme obesity with bmi > 40 kg/m2 12. on medications that would influence exercise performance such as beta blockers or antiretroviral therapy 13. ongoing tobacco and/or nicotine product use 14. enrolled in another interventional clinical research trial 15. any other medical or health condition(s) that unduly increases the risk of exercise testing or training, affects the normal physiologic response to exercise testing or training, and/or would otherwise interfere with the ability to interpret the data as determined by the pi inclusion of vulnerable participants: participation of employees: nih employees may be enrolled in this study as this population meets the study entry criteria. neither participation nor refusal to participate as a participant in the research will have an effect, either beneficial or adverse, on the participant s employment or position at nih. every effort will be made to protect participant information, but such information may be available in medical records and may be available to authorized users outside of the study team in both an identifiable and unidentifiable manner. the nih information sheet on employee research participation will be made available.

an individual who meets any of the following criteria will be excluded from participation in this study: 1. above normal performance (i.e, greater than or equal to 100% predicted) in the 6mwt based on normative data for gender and age 2. history or cardiac condition as determined by nih cardiology to be unsafe for exercise participation (e.g. ischemic heart disease, right- or left-sided heart failure, cor pulmonale or pulmonary hypertension, dilated or hypertrophic cardiomyopathy or non-idiopathic cardiomyopathy) 3. significant hepatic or renal dysfunction 4. cancer diagnosis with evidence of metastasis or a life expectancy of less than one year 5. history of stroke resulting in impairments in functional mobility that limits safe participation 6. active substance abuse including etoh 7. severe psychiatric disease, not responsive to treatment or medication 8. history of diabetes and on insulin pump therapy, or uncontrolled diabetes with hba1c > 9.0% 9. pregnancy 10. acceptance onto a lung transplant waiting list 11. extreme obesity with bmi > 40 kg/m2 12. on medications that would influence exercise performance such as beta blockers or antiretroviral therapy 13. ongoing tobacco and/or nicotine product use 14. enrolled in another interventional clinical research trial 15. any other medical or health condition(s) that unduly increases the risk of exercise testing or training, affects the normal physiologic response to exercise testing or training, and/or would otherwise interfere with the ability to interpret the data as determined by the pi inclusion of vulnerable participants: participation of employees: nih employees may be enrolled in this study as this population meets the study entry criteria. neither participation nor refusal to participate as a participant in the research will have an effect, either beneficial or adverse, on the participant s employment or position at nih. every effort will be made to protect participant information, but such information may be available in medical records and may be available to authorized users outside of the study team in both an identifiable and unidentifiable manner. the nih information sheet on employee research participation will be made available.

an individual who meets any of the following criteria will be excluded from participation in this study: 1. above normal performance (i.e, greater than or equal to 100% predicted) in the 6mwt based on normative data for gender and age 2. history or cardiac condition as determined by nih cardiology to be unsafe for exercise participation (e.g. ischemic heart disease, right- or left-sided heart failure, cor pulmonale or pulmonary hypertension, dilated or hypertrophic cardiomyopathy or non-idiopathic cardiomyopathy) 3. significant hepatic or renal dysfunction 4. cancer diagnosis with evidence of metastasis or a life expectancy of less than one year 5. history of stroke resulting in impairments in functional mobility that limits safe participation 6. active substance abuse including etoh 7. severe psychiatric disease, not responsive to treatment or medication 8. history of diabetes and on insulin pump therapy, or uncontrolled diabetes with hba1c > 9.0% 9. pregnancy 10. acceptance onto a lung transplant waiting list 11. extreme obesity with bmi > 40 kg/m2 12. on medications that would influence exercise performance such as beta blockers or antiretroviral therapy 13. ongoing tobacco and/or nicotine product use 14. enrolled in another interventional clinical research trial 15. any other medical or health condition(s) that unduly increases the risk of exercise testing or training, affects the normal physiologic response to exercise testing or training, and/or would otherwise interfere with the ability to interpret the data as determined by the pi inclusion of vulnerable participants: participation of employees: nih employees may be enrolled in this study as this population meets the study entry criteria. neither participation nor refusal to participate as a participant in the research will have an effect, either beneficial or adverse, on the participant s employment or position at nih. every effort will be made to protect participant information, but such information may be available in medical records and may be available to authorized users outside of the study team in both an identifiable and unidentifiable manner. the nih information sheet on employee research participation will be made available.

an individual who meets any of the following criteria will be excluded from participation in this study: 1. above normal performance (i.e, greater than or equal to 100% predicted) in the 6mwt based on normative data for gender and age 2. history or cardiac condition as determined by nih cardiology to be unsafe for exercise participation (e.g. ischemic heart disease, right- or left-sided heart failure, cor pulmonale or pulmonary hypertension, dilated or hypertrophic cardiomyopathy or non-idiopathic cardiomyopathy) 3. significant hepatic or renal dysfunction 4. cancer diagnosis with evidence of metastasis or a life expectancy of less than one year 5. history of stroke resulting in impairments in functional mobility 6. active substance abuse including etoh 7. severe psychiatric disease, not responsive to treatment or medication 8. history of diabetes and on insulin pump therapy, or uncontrolled type 2 diabetes with hba1c > 9.0% 9. pregnancy 10. acceptance onto a lung transplant waiting list 11. extreme obesity with bmi > 40 kg/m2 12. on medications that would influence exercise performance such as beta blockers or antiretroviral therapy 13. ongoing tobacco and/or nicotine product use 14. enrolled in another interventional clinical research trial 15. any other medical or health condition(s) that unduly increases the risk of exercise testing or training, affects the normal physiologic response to exercise testing or training, and/or would otherwise interfere with the ability to interpret the data as determined by the pi inclusion of vulnerable participants: participation of employees: nih employees may be enrolled in this study as this population meets the study entry criteria. neither participation nor refusal to participate as a participant in the research will have an effect, either beneficial or adverse, on the participant s employment or position at nih. every effort will be made to protect participant information, but such information may be available in medical records and may be available to authorized users outside of the study team in both an identifiable and unidentifiable manner. the nih information sheet on employee research participation will be made available.

an individual who meets any of the following criteria will be excluded from participation in this study: 1. above normal performance (i.e, greater than or equal to 100% predicted) in the 6mwt based on normative data for gender and age 2. history or cardiac condition as determined by nih cardiology to be unsafe for exercise participation (e.g. ischemic heart disease, right- or left-sided heart failure, cor pulmonale or pulmonary hypertension, dilated or hypertrophic cardiomyopathy or non-idiopathic cardiomyopathy) 3. significant hepatic or renal dysfunction 4. cancer diagnosis with evidence of metastasis or a life expectancy of less than one year 5. history of stroke resulting in impairments in functional mobility 6. active substance abuse including etoh 7. severe psychiatric disease, not responsive to treatment or medication 8. history of diabetes and on insulin pump therapy, or uncontrolled type 2 diabetes with hba1c > 9.0% 9. pregnancy 10. acceptance onto a lung transplant waiting list 11. extreme obesity with bmi > 40 kg/m2 12. on medications that would influence exercise performance such as beta blockers or antiretroviral therapy 13. ongoing tobacco and/or nicotine product use 14. enrolled in another interventional clinical research trial 15. any other medical or health condition(s) that unduly increases the risk of exercise testing or training, affects the normal physiologic response to exercise testing or training, and/or would otherwise interfere with the ability to interpret the data as determined by the pi inclusion of vulnerable participants: participation of employees: nih employees may be enrolled in this study as this population meets the study entry criteria. neither participation nor refusal to participate as a participant in the research will have an effect, either beneficial or adverse, on the participant s employment or position at nih. every effort will be made to protect participant information, but such information may be available in medical records and may be available to authorized users outside of the study team in both an identifiable and unidentifiable manner. the nih information sheet on employee research participation will be made available.