Clearance in Primary Ciliary Dyskinesia

The investigators will perform an open label, single-arm interventional pilot study with all participants undergoing the interventions (exercise, and exercise with HS pretreatment) and serving as their own control to evaluate the effects of exercise on non-ciliary mucus clearance mechanisms in PCD to better identify role of GLT and CC. The investigators will also evaluate the effect of pretreatment with HS on GLT (if present) and CC, to determine if these mechanisms of mucus clearance are modifiable by future therapies in PCD and other muco-obstructive lung diseases. Patients will be asked to attend a total of 3 study visits: screening visit 1 (V1), baseline exercise MCC (visit 2 (V2) or visit 3 (V3)), and HS pretreatment MCC (V2 or V3). Patients will be randomized to perform their baseline exercise MCC scan first or their HS pretreatment MCC scan first to minimize introduction of bias. The time between V1 and V2 will be 3 days to 28 days to allow for flexibility of scheduling, but participants already prescribed HS will be required to undergo a washout period of at least 3 days. V3 will take place at least 3 days after V2 to allow for remaining MCC isotope washout. At V1, tolerability and change in airway caliber in response to HS will be assessed by symptom assessment and spirometry, along with the performance of an exercise assessment to inform the exercise protocol in V2 and V3. From the baseline exercise MCC visit, the primary outcome of Whole Lung Total GLT will be measured. Through comparing the data from the exercise MCC visit and the HS pretreatment MCC visit, change in Whole Lung Total GLT and CC will be determined.