Hi welcome to the health care magic You are using ipratropium bromide inhaler Hence you are mostly having COPD like obstructive lung disease... In such respiratory condition either bronchitis or emphysema breathlessness can occur after excess exercise and another condition is secondary heart failure might present leading dyspnea ex. Cor pulmonale right side heart failure Graded exercise is beneficial in COPD Avoid smoking if habit Keep environment exposure minimum esp dust and smoke If needed to rule out heart failure EKG or echo needs to be done Take care Consult pulmonologoist with keeping all this in mind Hope your concern solved