Inclusion criteria:
Patients with scleroderma according to the 2013 Eular criteria
FVC less than 80 percent or CT involvement more than 10 percent
No change in the medications taken by patients during the last 3 months
These patients should have the ability to do exercise in the hospital and at home
Exclusion criteria:
Overlap syndrome and MCTD
Inability to perform exercise
Contraindications to CPET include:1) Unstable angina, 2) Uncontrolled arrhythmia, 3) Severe aortic stenosis,4) Arterial oxygen with pulse oximetry less than 85% in room air,5) Severe untreated arterial hypertension at rest (SBP200mmHg) (DBP120mmmHg ), 6) Hypertrophic cardiomyopathy 7) Significant orthopedic disorder, 8) Mental disorder,9) Clinical signs of heart failure (pulmonary or peripheral edema) or EF less than 50%, 10) Severe valvular heart disease,11) Pulmonary hypertension >50 mmHg, 12) Acute pulmonary embolism - 13) Sinus tachycardia more than 120,14) Pericarditis, 15) Acute myocarditis, 16) Uncompensated heart failure, 17) Acute systemic disease or fever, 18 ) Coronary disease in the last 4 weeks -19) Metabolic disease such as acute thyroiditis