* neuromotor, musculoskeletal, or rheumatoid disorders that are exacerbated by exercise or conditions preventing cooperation * covid-19 infection occurring \> 6 months prior to screening date * contraindications to symptom-limited maximal exercise testing * individuals without access to a device with ios (apple devices such as iphone, ipad, macbook, etc.) * patient-reported diagnosis of severe arterial hypertension * patient reported metabolic disease * patient reported uncontrolled asthma * inmates * pregnancy * patient reported supplemental o2 use * presence of beards * patient reported diagnosis of claustrophobia * non-english speaking

* neuromotor, musculoskeletal, or rheumatoid disorders that are exacerbated by exercise or conditions preventing cooperation * covid-19 infection occurring \> 6 months prior to screening date * contraindications to symptom-limited maximal exercise testing * individuals without access to a device with ios (apple devices such as iphone, ipad, macbook, etc.) * patient-reported diagnosis of severe arterial hypertension * patient reported metabolic disease * patient reported uncontrolled asthma * inmates * pregnancy * patient reported supplemental o2 use * presence of beards * patient reported diagnosis of claustrophobia * non-english speaking

neuromotor, musculoskeletal, or rheumatoid disorders that are exacerbated by exercise or conditions preventing cooperation covid-19 infection occurring > 6 months prior to screening date contraindications to symptom-limited maximal exercise testing individuals without access to a device with ios (apple devices such as iphone, ipad, macbook, etc.) patient-reported diagnosis of severe arterial hypertension patient reported metabolic disease patient reported uncontrolled asthma inmates pregnancy patient reported supplemental o2 use presence of beards patient reported diagnosis of claustrophobia non-english speaking

neuromotor, musculoskeletal, or rheumatoid disorders that are exacerbated by exercise or conditions preventing cooperation covid-19 infection occurring > 6 months prior to screening date contraindications to symptom-limited maximal exercise testing individuals without access to a device with ios (apple devices such as iphone, ipad, macbook, etc.) patient-reported diagnosis of severe arterial hypertension patient reported metabolic disease patient reported uncontrolled asthma inmates pregnancy patient reported supplemental o2 use presence of beards patient reported diagnosis of claustrophobia non-english speaking